Question 1

What are MEP Plans?

Accepted Answer

MEP plans are the engineering drawings that show how a building's Mechanical, Electrical, and Plumbing systems will be designed, sized, installed, and coordinated. For a California ADU, they are the documents a plan checker uses to confirm your heating and cooling, power and lighting, and water and waste systems are safe and code-compliant before a permit is issued.The three disciplines explainedEach letter is a full engineering discipline with its own set of plan sheets, labeled M-1/M-2, E-1/E-2, and P-1/P-2:Mechanical (M) — heating, cooling, and ventilation. This covers the HVAC system (most commonly a ductless mini-split heat pump in California ADUs), heat load calculations, equipment schedules, bathroom and kitchen exhaust, and the whole-building ventilation required by ASHRAE 62.2 and Title 24.Electrical (E) — power and lighting. This covers the electrical floor plan, panel schedule, NEC/CEC load calculations, dedicated appliance and EV circuits, GFCI and AFCI protection, and smoke/CO detector locations.Plumbing (P) — water, waste, and gas. This covers water supply routing and sizing, the drain-waste-vent (DWV) system, the water heater, fixture schedules confirming CALGreen low-flow compliance, and gas piping where allowed.What a permit-ready set actually containsA complete California ADU MEP set is more than a floor plan with symbols on it. It includes a cover sheet citing the applicable codes (CBC, CEC, CPC, CMC, and the current Title 24 energy code), formal calculations (Manual J heat load and NEC Article 220 electrical load), equipment schedules listing make, model, capacity, and efficiency ratings, and all the notes and callouts a reviewer expects. These are construction documents, not preliminary sketches.How MEP plans differ from architectural plansIt's a common point of confusion. Architectural plans show what the building looks like and how it is laid out — room dimensions, window and door locations, exterior elevations. MEP plans show only the engineering systems inside: the ductwork, circuits, pipes, and equipment schedules. The two are separate documents that must be coordinated with each other, which is why an MEP engineer works from your completed architectural drawings rather than the other way around. Structural plans are a third, separate discipline covering foundations, framing, and load-bearing elements.Why they matter for your projectInspectors and building departments cannot verify code compliance on systems they cannot see documented. Well-prepared MEP plans help ensure the ADU is safe, energy efficient, and capable of supporting a full household — and they are the single most effective way to avoid the plan check corrections that delay permits. They also serve as the reference document at every construction inspection, from rough-in (before the walls close) through final, so accurate plans translate directly into clean inspections. Each discipline is covered in depth on its own page: see Mechanical Plans, Electrical Plans, and Plumbing Plans.Requirements vary by jurisdiction — confirm the specifics for your project with your local building department. If you want the engineering handled end-to-end, our Full MEP Package delivers all three disciplines as one coordinated, permit-ready set.

Question 2

What does MEP stand for?

Accepted Answer

MEP stands for Mechanical, Electrical, and Plumbing — the three core building systems. Mechanical (M): heating, ventilation, and air conditioning (HVAC), including heat pumps, furnaces, mini-split systems, exhaust fans, ductwork, and ventilation. Electrical (E): power distribution, electrical panels, outlets, lighting, switches, grounding, smoke and carbon monoxide detectors, and electrical load calculations. Plumbing (P): water supply lines, drainage, vent piping, sewer connections, gas piping, plumbing fixtures, and water heating equipment. Together, these three disciplines allow a structure to operate safely and efficiently.

Question 3

Do I need MEP Plans for my ADU?

Accepted Answer

In the large majority of California jurisdictions, yes — an ADU is a fully independent dwelling that needs its own heating, electrical, and plumbing, and building departments require Mechanical, Electrical, and Plumbing information to verify those systems are safe and code-compliant before issuing a permit. The exact requirements depend on your city, project scope, and design complexity, but very few ADU projects clear plan check without MEP documentation.Why an ADU triggers MEP reviewAn ADU must provide complete independent living facilities under California law: a full kitchen, a bathroom, hot water, heating, and connections to power, water, and waste. That means a self-contained set of building systems — essentially a small house. A plan reviewer needs to confirm the HVAC is sized correctly, the electrical panel can carry the load, and the plumbing drains and vents properly. None of that can be verified without engineered drawings.Projects where MEP plans are especially criticalMEP plans become unavoidable when a project includes any of the following, all of which are common in ADUs:New HVAC systems (nearly every ADU)Electrical panel or service upgradesSolar photovoltaic (PV) and battery energy storage (ESS) provisionsNew plumbing systems and sewer connectionsUtility service upgradesGarage conversionsDetached ADUs built from scratchWhat about garage conversions and JADUs?Garage conversions still need full MEP plans even though a structure already exists. Garage wiring is built for non-habitable use, garages typically have no plumbing at all, and garage heaters are non-residential units that must be removed. Closing the garage door opening also eliminates the unintentional air exchange it provided, which means a new ASHRAE 62.2 ventilation system must be engineered. See our Garage Conversion MEP page for the specifics. Junior ADUs (JADUs, up to 500 SF within the existing home) have lighter requirements that vary by city, but at minimum electrical and mechanical plans are typically required.Which disciplines does your project actually need?Not every project needs all three sets, and that affects both your scope and your cost. As a general guide:Detached ADUs — typically need complete mechanical, electrical, and plumbing from scratch.Attached ADUs and additions — usually need full MEP for the new conditioned area, though some systems may tie into existing house infrastructure if capacity allows.Garage conversions — almost always need all three, because garage systems aren't adequate for residential use.JADUs — requirements vary by city, but at minimum electrical and mechanical are commonly required.If your project only needs one or two disciplines, you can order them individually — see mechanical, electrical, or plumbing plans.What happens if you skip themSubmitting an ADU application without the MEP information the city expects generally results in an incomplete notice or a list of plan check corrections, both of which stall the project before review can finish. Building departments need to verify compliance with building, electrical, mechanical, plumbing, and energy codes before issuing a permit, and they can't do that from architectural drawings alone. Providing complete MEP documentation up front is the most reliable way to keep the 60-day review clock moving.If you're unsure whether your specific project requires formal MEP plans, the safest path is to confirm with your local building department or an engineering professional before you submit.Requirements vary by jurisdiction. If your project needs all three disciplines, the Full MEP Package is the most coordinated and cost-effective option — see pricing or start an order.

Question 4

What is included in MEP Plans?

Accepted Answer

A complete set of ADU MEP plans includes detailed, permit-ready engineering for all three disciplines — Mechanical, Electrical, and Plumbing — plus a cover sheet, code references, formal calculations, and equipment schedules. Below is what each part of the set contains.Mechanical sheets (M-1, M-2)HVAC system type and layout, with indoor and outdoor unit locationsHeat load calculations (Manual J) sizing the equipment to the ADUAn equipment schedule listing make, model, capacity (BTU/hr), and efficiency ratingsDuctwork routing and sizing for ducted systemsWhole-building ventilation per ASHRAE 62.2 and Title 24Kitchen range hood ducted to exterior, bathroom exhaust fans, and condensate drainageElectrical sheets (E-1, E-2)An electrical floor plan showing every outlet, switch, light, and fixtureA panel schedule listing each circuit with description, amperage, and voltageA formal load calculation per NEC/CEC Article 220Dedicated circuits for HVAC, range, dishwasher, washer/dryer, and EV chargerGFCI notation (kitchens, baths, garages, outdoors) and AFCI notation (bedrooms, living areas)Smoke and CO detector locations, plus EV-ready conduit and any solar/ESS provisionsPlumbing sheets (P-1, P-2)A plumbing floor plan with all fixture locationsA fixture schedule confirming CALGreen low-flow complianceWater supply design with pipe routing and sizingA drain-waste-vent (DWV) system with correct slope, vent stacks, and cleanoutsSewer connection details and water heater specifications (type, efficiency, venting, seismic strapping, T&P relief valve)Backflow prevention and gas piping where gas appliances are allowedThe supporting documents that tie it togetherBeyond the discipline sheets, a permit-ready set includes a cover sheet with the project address, applicable codes (CBC, CEC, CPC, CMC, Title 24), and general notes. The formal calculations — Manual J for mechanical and NEC Article 220 for electrical — are what plan checkers most often look for, and their absence is a leading cause of corrections. The exact contents vary by project type and local requirements, so confirm specifics with your building department.Permit-ready vs. design drawingsIt's worth understanding what "included" really means. Design drawings show general intent and are useful for planning and estimating, but they are not what a building department accepts. A permit-ready set is a fully completed construction document that meets the city's specific format and content requirements: a complete cover sheet with code references, full equipment schedules with manufacturer specifications, formal calculations, all required notes and callouts, GFCI/AFCI notation, and proper sheet labeling. What we deliver is permit-ready — not a preliminary sketch.How delivery and format workThe finished plans are delivered as PDFs formatted for 24" x 36" printing, the standard sheet size California building departments require for permit submittal. These files are compatible with electronic plan review portals such as ePlanLA and eTRACKiT and can be printed at any large-format print shop for physical submittal. Every order also includes two revisions and city corrections at no extra charge, so the set you receive can be adjusted as your project — or the plan checker — requires.Want all three disciplines coordinated as one set? That is exactly what the Full MEP Package delivers. You can also order a single discipline — mechanical, electrical, or plumbing — if your project only needs one.

Question 5

Are MEP Plans the same as architectural plans?

Accepted Answer

No. Architectural and MEP plans serve different purposes but must work together as a coordinated design package. Architectural plans focus on building layout, room dimensions, doors and windows, exterior appearance, floor plans, elevations, and building-code and life-safety requirements. MEP plans focus on heating and cooling systems, electrical systems, lighting layouts, water distribution, drainage systems, and utility coordination. Think of architectural plans as showing what the building looks like, while MEP plans show how the building functions.

Question 6

Do MEP Plans need an engineer stamp?

Accepted Answer

Engineer-stamp requirements depend on the project type, scope, complexity, and local jurisdiction. Many commercial projects require plans prepared and stamped by a licensed engineer. Residential and ADU requirements vary by city and project complexity — some projects may require engineering calculations, while others may be permitted with simpler documentation. If an engineer stamp is required for your project, your engineering team can help determine the appropriate requirements before submission.

Question 7

What is included in Mechanical Plans?

Accepted Answer

Our Mechanical Plans are a permit-ready drawing set that documents the complete HVAC and ventilation design for your ADU — the equipment, its sizing math, where every component goes, and how the air moves. They give the plan reviewer everything needed to confirm the system is safe, correctly sized, and code-compliant, and they coordinate cleanly with your Title 24 report.What the drawing set containsA typical ADU mechanical set runs one or two sheets (M-1, M-2) and includes:Mechanical floor plan showing the indoor equipment, supply/return points, exhaust fans, and the outdoor condenser location with required property-line and window setbacks.Equipment schedule — a table listing each unit's manufacturer, model number, capacity in BTU/hr, and efficiency ratings (SEER2/HSPF2 for heat pumps), so the reviewer can verify Title 24 minimums.Heat-load (Manual J) summary establishing the peak heating and cooling loads the equipment is sized to.Mini-split head and condenser layout with refrigerant line-set routing drawn from each indoor head to the outdoor unit.Duct layout where a ducted system is used, including register locations and duct sizing.Ventilation design per ASHRAE 62.2 — the whole-building mechanical ventilation rate and equipment, plus local exhaust (bath fans, kitchen hood ducted to the exterior).Condensate drainage routing for the indoor units.Combustion air details if any gas appliance is permitted in your jurisdiction.General notes and a title block citing the applicable codes (CMC, CBC, Title 24) and identifying the project.How it coordinates with Title 24The equipment listed on the mechanical schedule must match the equipment modeled in your energy-compliance documents. When you bundle a Title 24 report, we keep the make, model, and efficiency ratings consistent across both, which prevents one of the most common plan-check corrections — a mismatch between the drawings and the energy calcs.What you receive — checklistMechanical floor plan with equipment locations and setbacks.Equipment schedule (make, model, BTU/hr, efficiency).Manual J load-calculation summary.Line-set and/or duct routing.ASHRAE 62.2 whole-building ventilation plus local exhaust.Condensate, combustion air (if gas), notes, and title block.Mechanical plans are sized to your ADU's square footage and climate zone, not pulled from a template — the load calculation drives the equipment selection.Sheet counts, local amendments, and submittal requirements vary by jurisdiction — confirm specifics with your local building department. Our Mechanical Plans start at $995 as a single discipline, and you can pair them with electrical and plumbing in the size-scaled Full MEP package. See pricing or start your order.

Question 8

What HVAC system is best for an ADU?

Accepted Answer

For the overwhelming majority of California ADUs, the best HVAC system is a ductless mini-split heat pump — it provides both heating and cooling in one all-electric unit, needs no ductwork, and is the most direct route to Title 24 compliance. Larger multi-bedroom units sometimes favor a ducted heat pump, but the underlying technology is the same: a heat pump.Why heat pumps win for ADUsCalifornia's mild, Mediterranean climate is nearly ideal for heat-pump operation, and the 2025 energy code treats heat pumps as the prescriptive baseline for new-construction space conditioning. A heat pump moves heat rather than burning fuel, delivering roughly two to four units of heating for every unit of electricity it consumes — far more efficient than electric-resistance baseboards. Because it contains no combustion, it also satisfies the all-electric reach codes adopted by Los Angeles, San Jose, San Francisco, Oakland, and dozens of other California cities.Matching the system to the ADUADU typeRecommended systemStudio / open-plan under ~600 SFSingle-zone ductless mini-split (one head)1-bedroomTwo-zone mini-split (living + bedroom)2-bedroomThree-zone mini-split, or a ducted heat pump1,000+ SF, multiple roomsMulti-zone mini-split or ducted heat pump with central air handlerClimate-zone considerationsCoastal and inland zones (1, 3, 5–13): standard high-efficiency mini-splits perform excellently.Desert zones (14, 15): prioritize cooling capacity and size carefully to the zone's high summer design temperatures.Mountain zone (16) and cold edges of zones 1 and 11: specify a cold-climate-rated heat pump that maintains capacity below freezing.How to decide — checklistConfirm your climate zone by parcel address.Run a Manual J to establish per-room heating and cooling loads.Check whether your city's reach code prohibits gas (it likely points you to all-electric anyway).Choose ductless for compact or low-ceiling plans; consider ducted only when there is room to route ducts and you want a single thermostat.Verify the chosen equipment meets current Title 24 efficiency minimums.Add ASHRAE 62.2 whole-building ventilation as a separate documented system.What about gas furnaces and other options?A gas furnace heats but doesn't cool, requires a separate AC system to handle California summers, and is prohibited outright in cities with all-electric reach codes — so it rarely makes sense for a new ADU. Electric-resistance baseboards are cheap to install but expensive to run and carry a poor Title 24 efficiency margin. A heat pump avoids both problems by combining efficient heating and cooling in one unit, which is why nearly every modern ADU design centers on one.Code thresholds and local mandates vary by jurisdiction — confirm current details with your local building department. Our mechanical plans specify the exact system, sized to your ADU and climate zone, with the Manual J and equipment schedule included. See our mechanical guide for deeper detail, or start an order.

Question 9

Should I use a mini-split?

Accepted Answer

For most California ADUs, yes — a ductless mini-split heat pump is the default and usually the smartest choice. It heats and cools in one all-electric unit, eliminates ductwork (preserving precious ceiling height in a small building), runs very efficiently, and is the path of least resistance through Title 24 plan check.When a mini-split is the right callLimited ceiling height or no attic/chase space for ducts — the mini-split's small line set needs only a 3-inch wall penetration.You want room-by-room control — a multi-zone system lets an occupied bedroom and an empty living room hold different setpoints.Your city has an all-electric reach code — mini-splits contain no combustion and comply directly.You want to maximize Title 24 margin — quality mini-splits typically exceed minimum SEER2/HSPF2 thresholds by a wide margin, and eliminating ducts removes duct-leakage losses that often cause HERS test failures.Single-zone vs. multi-zoneA single-zone system pairs one outdoor condenser with one indoor head — ideal for studios and open-plan ADUs under roughly 600 SF, where air circulates freely. A multi-zone system feeds two, three, or more heads from one condenser, with each enclosed bedroom typically getting its own head so it holds temperature with the door closed. The engineer sizes the condenser and each head from per-room load calculations rather than installing identical heads everywhere.Honest trade-offsA wall-mounted head is visible in each conditioned room (ceiling-cassette and concealed-duct heads are alternatives).Multi-zone installed cost runs higher than a single head.Each enclosed room generally needs its own head, so head count tracks the floor plan.If the trade-offs of visible heads or multiple zones are a concern in a larger, multi-room ADU, a ducted heat pump with a central air handler is the main alternative — but for compact ADUs, the ductless mini-split is hard to beat.Decision checklistCount the separately enclosed habitable rooms — bedrooms each want a zone.Run a per-room Manual J for head sizing.Confirm the condenser's total capacity covers the connected heads.Verify line-set routing and condenser setbacks are feasible on your site.Check that every habitable room receives heat (a code requirement).System availability and sizing vary by project and brand, and local rules vary by jurisdiction — confirm with your local building department. Our mechanical plans specify the exact heads, condenser, and routing with the Manual J included. See pricing or order here.

Question 10

Should I use a heat pump?

Accepted Answer

In nearly every California ADU, yes — a heat pump is the right choice and increasingly the required one. It delivers heating and cooling from a single all-electric unit, runs far more efficiently than electric-resistance heat, satisfies the state's heating mandate, and is the prescriptive baseline under the 2025 energy code.How a heat pump works (and why "it won't heat in cold" is outdated)A heat pump doesn't generate heat by burning fuel or running resistance coils — it moves heat with a refrigerant cycle. In summer it pulls heat out of the indoor air; in winter the cycle reverses and it extracts heat from outdoor air, even when it's cold, and delivers it inside. Because moving heat takes far less energy than creating it, a modern unit delivers roughly two to four units of heat per unit of electricity. Older heat pumps lost capacity as temperatures dropped, but modern cold-climate-rated models use variable-speed inverter and vapor-injection compressors to hold rated capacity well below freezing.Heat pump vs. the alternativesSystemHeats?Cools?All-electric?Title 24 fitHeat pump (mini-split or ducted)YesYesYesPrescriptive baselineElectric-resistance baseboardYesNoYesPoor efficiency marginGas furnaceYesNoNoOften prohibited by reach codesReasons to choose a heat pumpTwo functions, one unit — it satisfies the code requirement to maintain 68°F in every habitable room and provides cooling, which is effectively essential in the hot inland and desert zones.All-electric compliance — required where reach codes prohibit gas, and favorable for Title 24 everywhere.Low operating cost in California's mild climate.Incentive eligibility — many state, utility, and federal programs target heat pump installations (programs and amounts change frequently; verify current eligibility for your address).Selection checklistConfirm your climate zone by parcel address.Run a Manual J to size the unit to the actual load.In Zone 16 (and cold edges of 1 and 11), specify a cold-climate-rated model and check capacity at the design temperature, not just at 47°F.Verify the unit meets current Title 24 SEER2/HSPF2 minimums.Note refrigerant-charge HERS verification, required in all 16 zones.A common worry, addressedOwners sometimes ask whether one heat pump can carry both the coldest winter morning and the hottest summer afternoon. The answer is yes, when it's sized from a real Manual J rather than a rule of thumb. The load calculation pins the equipment to your ADU's actual peak heating and cooling demand at your zone's design temperatures, so a single correctly specified unit holds setpoint year-round without the short-cycling that comes from oversizing. In multi-room ADUs, a multi-zone configuration adds independent control room by room while still running off one outdoor condenser.Equipment ratings and local mandates vary by jurisdiction and code cycle — confirm with your local building department. Our mechanical plans specify the exact heat pump, sized and scheduled for your ADU, and bundle cleanly with a Title 24 report. Start your order when ready.

Question 11

What is a Manual J calculation?

Accepted Answer

Manual J is the standardized method for calculating a building's peak heating and cooling loads, developed by the Air Conditioning Contractors of America (ACCA) and recognized as the standard by California building codes. It produces the exact BTU/hr your ADU needs at design conditions — the number the engineer uses to correctly size the HVAC equipment, replacing guesswork with engineering.What it calculatesA Manual J models how heat enters and leaves the ADU at the worst-case summer and winter conditions for your climate zone, accounting for:Wall, ceiling, and floor areas and their construction.Window area and orientation (north/south/east/west), because solar gain varies dramatically by direction.U-factors — the thermal performance of each assembly and the windows.Air infiltration — how tightly the building is sealed.Internal heat gains from occupants, lighting, and appliances.Outdoor design conditions for the project's California climate zone.Duct location and leakage, for ducted systems.Why correct sizing mattersThe instinct to "go bigger to be safe" backfires with HVAC. Oversized equipment short-cycles — turning on and off too frequently — which hurts humidity control, comfort, and compressor life. Undersized equipment can't hold setpoint on the hottest or coldest design days. Manual J finds the right capacity so the system runs efficiently and comfortably, and it gives the plan reviewer the documentation needed to approve the equipment selection. Building departments increasingly require the calculation itself in the plan set, not just an equipment schedule.What the engineer needs from youThe floor plan with dimensions and ceiling heights.A window schedule — size, location, orientation, and glazing type.Wall, ceiling, and floor construction — insulation R-values if known.The ADU type (detached, attached, garage conversion) and the project address.The climate zone is determined automatically from the project address, so you don't need to look it up, and if insulation values are unknown the engineer applies California code-minimum defaults — keeping the calculation defensible while construction details are finalized.Manual J is the engineering behind the equipment on your plans. Including it up front prevents one of the most common ADU plan-check corrections.Prep checklistProvide a dimensioned floor plan with ceiling heights.List every window: size, orientation, and glazing type.Note insulation R-values, or let the engineer use code defaults.Identify the ADU type and project address.Flag unusual conditions — large west-facing glass, vaulted ceilings, exposed floors.Design assumptions and code defaults vary by climate zone and code cycle — confirm specifics with your local building department. Our mechanical plans include the Manual J summary and the matching equipment schedule, so the sizing math travels with the drawings. See how it works, or start your order.

Question 12

Do Mechanical Plans include ventilation?

Accepted Answer

Yes. Ventilation is a core part of our Mechanical Plans — the drawing set documents both the mandatory ASHRAE 62.2 whole-building mechanical ventilation system and the local exhaust (bathroom fans and a kitchen hood). Ventilation is a separate Title 24 requirement from heating and cooling, and it is one of the most commonly missed items on incomplete ADU plans, so we design and document it explicitly.The two layers of ventilation we showWhole-building (dilution) ventilation per ASHRAE 62.2 — a continuous, mechanically driven supply of outdoor air sized to the ADU's floor area and bedroom count. The plan specifies the strategy, equipment make/model, CFM, and controls. This is required in every new ADU regardless of size and is not waivable.Local (spot) exhaust — bathroom exhaust fans and a kitchen range hood ducted to the exterior (recirculating hoods generally don't satisfy the California Mechanical Code). These are in addition to whole-building ventilation, not a substitute.What appears on the plan setThe calculated whole-building ventilation rate, derived from floor area and bedroom count.The chosen strategy — continuous exhaust fan, balanced ERV/HRV, or supply ventilation through the air handler.The ventilation equipment in the schedule: make, model, and rated CFM.Controls confirming continuous operation.Bath fan and kitchen-hood locations with duct runs to the exterior.A note for HERS verification of ventilation airflow, which a rater field-measures.Typical ADU ventilation ratesADU sizeApprox. continuous ventilation800 SF, 1 bedroom~30–40 CFM1,200 SF, 2 bedroom~45–55 CFMThese illustrate the order of magnitude; the engineer calculates the exact target for your unit.A clean plan check depends on showing ventilation as its own designed system — not assuming a bath fan covers it. ASHRAE 62.2 whole-building ventilation and local exhaust are distinct requirements.Why ventilation is non-negotiable in a tight ADUModern ADUs are built tight to meet the energy code, which means they no longer "breathe" through gaps the way old construction did. Without deliberate mechanical ventilation, moisture, CO2, cooking byproducts, and VOCs from finishes accumulate indoors. That is exactly the problem ASHRAE 62.2 solves, and it is why a HERS rater field-measures the installed airflow — a system that looks right on paper still has to deliver the required CFM in the field. Designing it into the plans up front, with the correct controls and CFM, is what keeps both plan check and final inspection clean.Ventilation rates and verification requirements vary by code cycle and jurisdiction — confirm current details with your local building department. Our mechanical plans include the ASHRAE 62.2 design, calculated rate, and equipment schedule, and pair cleanly with a bundled Title 24 report. See pricing or start your order.

Question 13

What is included in Electrical Plans?

Accepted Answer

Our ADU Electrical Plans are a permit-ready drawing set — typically sheets E-0 through E-2 — that gives your city's plan reviewer everything needed to approve the electrical scope, and your electrician everything needed to build it. Every set is drawn to the current California Electrical Code (the CEC, which adopts the NEC with California amendments) and coordinated with Title 24.What's on the sheetsA complete California ADU electrical set generally contains the following, all referenced to your specific floor plan and address:Power plan — every receptacle (general-use, dedicated, and GFCI), switch, and junction box located on the floor plan, with mounting heights and dedicated-circuit callouts.Lighting plan — fixture locations, switching, and high-efficacy lighting notes coordinated with your Title 24 report for energy-code compliance.Panel schedule(s) — every branch circuit listed with description, breaker size, voltage, and AFCI/GFCI designation, plus spare/reserved spaces.Single-line / riser diagram — the service or feeder path from the main house panel to the ADU subpanel (or separate meter), showing conductor and conduit sizing, the main breaker, and grounding.NEC/CEC Article 220 load calculation — the engineered demand calculation that justifies the panel amperage (see the dedicated FAQ below).Grounding and bonding details — the four-wire subpanel connection, isolated neutral, grounding electrode system, and bonding notes for a detached structure.Smoke and CO alarm locations per the California Residential Code, shown on the floor plan.EV-ready provisions — reserved breaker space and a conduit pathway to a designated charging location.Solar and ESS-ready provisions where the applicable energy code requires them for newly constructed detached ADUs.General notes and a symbols legend citing the applicable code edition and standard installation requirements.The code-mandated circuits we lay outBeyond the drawings themselves, the set specifies the branch circuits California requires for a dwelling unit, so nothing is missed in the field:Two 20-amp small-appliance circuits serving the kitchen countertop receptacles.A dedicated 20-amp laundry circuit and a dedicated 20-amp bathroom receptacle circuit.GFCI protection at kitchen counters, bathrooms, garages, outdoor receptacles, and anything within 6 feet of a sink.AFCI protection on the 120V circuits serving bedrooms and most habitable rooms.Dedicated circuits for the range/cooktop, water heater, HVAC, dishwasher, disposal, and washer/dryer.How the electrical set fits the larger packageElectrical is one of three disciplines. Many cities want all three submitted together, which is why most owners bundle electrical with mechanical and plumbing in a Full MEP package so the heat pump, water heater, and panel sizing all agree. A single discipline starts at $995; Full MEP starts at $1,495, scaled by ADU square footage. Title 24 documentation, when required, is +$240. See pricing for current options.Requirements vary by jurisdiction and utility — confirm the exact sheet and submittal requirements with your local building department and serving utility before you order.Two revisions plus any city plan-check corrections are included with every set, so if the reviewer asks for a change, we make it. See how it works or place an order to get started.

Question 14

Does my ADU need a panel upgrade?

Accepted Answer

Maybe — and the only reliable way to know is a formal NEC Article 220 load calculation that adds the new ADU load on top of your existing house load and checks the total against your main service. A panel or service upgrade is triggered when that combined demand exceeds what the existing main can safely carry, not by ADU square footage or a rule of thumb.The common scenariosExisting main serviceLikely outcome100A mainOften insufficient for house + ADU; a load calc frequently shows an upgrade is needed, especially for all-electric ADUs.200A main with available capacityFrequently can host a 100–125A ADU subpanel — but the calculation must confirm it for your actual loads.200A main already near full loadMay require a larger panel (225A or 320A) or a separate utility service for the ADU.An all-electric ADU pushes harder on the main than a gas-equipped one, because induction cooking, a heat pump water heater, heat pump HVAC, and EV charging all become electrical loads. That makes an upgrade more likely on older services.What an upgrade involvesCost. Main service or panel upgrades commonly run in the range of $3,500–$7,000 depending on amperage, panel location, and whether the meter base and service entrance also change.Utility coordination. The utility must de-energize at the meter to perform the work, so a service upgrade typically carries 6–12 weeks of utility lead time — often longer than the building permit itself.Inspection. The new panel needs proper working clearance (roughly 30 inches wide by 36 inches deep of clear space in front) and updated grounding/bonding.How to find out earlyRead your main panel's main breaker rating (100A, 125A, 200A) and count how many circuits are already in use.Decide all-electric vs. mixed-fuel — it materially changes the calculated demand.Have the Article 220 calculation run before you commit to a panel layout.If an upgrade looks likely, open the utility request in parallel with permitting so the timelines overlap.Alternatives when the main is maxed outAn upgrade isn't the only path. Depending on the calc and your utility's rules, options include:Upgrading the main service to 200A, 225A, or 320A so a subpanel can be added.A load-management device (such as a smart panel or an automatic load-shedding controller) that can let an existing service host the ADU without a full upgrade, where the jurisdiction accepts it.A separate utility service and meter for the ADU — sometimes required for distance or separate billing, and the right answer when the main truly can't be expanded.Which option is viable is a calculation-and-utility question, not a preference; the load calc points the way.Requirements vary by jurisdiction and utility — confirm with your local building department and serving utility.Every one of our electrical plan sets includes the load calculation that determines whether an upgrade is required and documents the feeder or service design either way. Start with how it works if you're unsure where your project stands.

Question 15

What size electrical panel does an ADU need?

Accepted Answer

Whatever a formal NEC Article 220 load calculation says — there is no valid square-footage shortcut. That said, most California ADUs land in a predictable range, and knowing the drivers helps you plan service and budget before the calc is finalized.Typical sizing by ADU profileADU profileTypical subpanelVery small ADU (under 500 SF), gas appliances60–100A (increasingly rare as all-electric spreads)Standard 1–2 bedroom, all-electric100–125ALarger all-electric ADU with EV charger150–200AIndustry practice favors 125 amps for a standard all-electric unit even when 100 amps technically passes the calc. The incremental cost of a larger panel and feeder is small next to retrofitting later, and the extra breaker spaces leave room for a future EV charger, battery, or hot tub.Why square footage doesn't decide itFloor area drives only the general lighting load — 3 VA per square foot. Everything else comes from the appliances. Two 750 SF ADUs can need very different panels: one with a gas range, gas water heater, and a small mini-split might calculate well under 100A, while an all-electric unit of the same size with induction cooking and a Level 2 charger can exceed it. That's where the variation lives.What pushes the number upInduction range: 40–50A dedicated circuit.Heat pump water heater: 20–30A.Heat pump / mini-split HVAC: 15–30A depending on capacity.Level 2 EV charger: 40–50A on its own dedicated circuit.Electric or heat-pump dryer: another dedicated circuit.Stack those and a fully electric ADU with EV charging can legitimately approach 150–200 amps of calculated demand even at modest square footage.Don't forget the main serviceThe ADU subpanel is fed from your main house panel, so its size is constrained by what the existing service can spare. A 100A main often can't carry both the house and a new ADU subpanel; a 200A main with capacity frequently can host a 125A subpanel — but only the load calculation confirms it for your specific existing loads.Breaker spaces matter as much as amperagePanel selection isn't only about the main breaker rating — it's also about how many circuits you have to fit. An all-electric ADU can easily need a dozen or more breakers once you count two small-appliance circuits, laundry, bathroom, lighting, receptacles, range, water heater, HVAC, dishwasher, disposal, and an EV charger. A panel that's adequate on amperage but short on spaces forces tandem breakers or an early replacement. This is a second reason to favor a 125A panel with generous spaces over a minimally sized 100A one — the extra slots leave room for a future battery, hot tub, or workshop circuit without a rework.Requirements vary by jurisdiction and utility — confirm with your local building department and serving utility.We run the Article 220 calc and justify the panel size in every electrical plan set; you can order a single discipline from $995. For deeper background, see the ADU electrical guide.

Question 16

Do ADUs require EV charger conduit?

Accepted Answer

In most California ADU projects, yes — new residential construction, including ADUs, is generally required to provide for electric-vehicle charging on the electrical plans. The minimum is usually EV-ready infrastructure: a conduit pathway from the panel to a designated charging location plus a reserved breaker space. Some jurisdictions require more.The three levels of requirementTierWhat's requiredEV-ready (common baseline)A reserved breaker space plus conduit run to a designated charging location.EV-capableActual 240V conductors run and terminated at the location, ready for a charger.Charger installedA Level 2 charging station physically installed and energized.Which tier applies depends on your city's reach code, so this is a verify-with-your-jurisdiction item. Missing EV provisions is one of the more frequent electrical plan-check corrections in California, which is why we show the conduit run, the charging location, and the reserved circuit on every set.Why it affects panel sizingA Level 2 charger runs at 240V and typically needs a 40–50A dedicated circuit. If your jurisdiction requires EV-capable or an installed charger, that load is included at full rating in the Article 220 calculation — which is a major reason all-electric ADUs with EV charging trend toward 150–200A service. Reserving the space and sizing for it up front avoids re-running the load calc and upgrading the panel later.Install during construction, not afterDuring construction: roughly $500–$1,500 to run conduit and reserve capacity while walls are open.As a retrofit: typically $2,000–$5,000 once walls are closed and finishes are in.Beyond the cost gap, retrofitting risks running out of panel capacity: if the load calc was done without the charger, adding 40–50A later can force a panel or even a service upgrade that a little foresight would have avoided.Plan-set checklistReserved two-pole breaker space shown on the panel schedule.Conduit routed from the panel to the charging location (garage wall, carport, or driveway-adjacent exterior wall).EV load included at full rating in the Article 220 calculation when EV-capable or installed.Charging location coordinated with the architectural plans so it doesn't conflict with parking or doors.Picking the charging locationBecause the conduit and (for EV-capable) the conductors are run during framing, the charging spot has to be chosen before walls close. A few practical pointers:Locate it within reach of where the EV will actually park — garage interior wall, carport post, or an exterior wall adjacent to the driveway.Keep the conduit run as short and direct as practical to the panel to control conductor cost and voltage drop.Coordinate the location with the architectural and site plans so it doesn't land behind a swinging door, a parked car's path, or required clearances.If the ADU shares a driveway with the main house, confirm whose panel the charger draws from — it affects both load calcs.Requirements vary by jurisdiction — confirm whether your city requires EV-ready, EV-capable, or an installed charger with your local building department.Our electrical plans show the EV conduit and reserved circuit so it clears plan check the first time.

Question 17

Do ADUs require smoke detectors?

Accepted Answer

Yes. A California ADU is a separate dwelling unit, so the California Residential Code requires both smoke alarms and carbon monoxide (CO) alarms in the unit, and their locations must be shown on the electrical plans. This is a code requirement, not an upgrade — units without them will not pass inspection.Where smoke alarms are requiredSmoke alarms are generally required in each of the following locations within the ADU:Inside each sleeping room (every bedroom).Outside each sleeping area, in the immediate vicinity of the bedrooms (hallway or adjacent space).On each story of the unit, including basements and habitable attics.Where more than one alarm is required, they generally must be interconnected, so that when one sounds, they all sound. New construction typically requires hardwired alarms with battery backup; alterations and conversions may have different allowances — confirm what applies to your project.Where carbon monoxide alarms are requiredCO alarms are required when the dwelling contains a fuel-burning appliance, a fireplace, or an attached garage. They are generally placed:Outside each separate sleeping area, in the immediate vicinity of the bedrooms.On each story of the dwelling, including basements.An all-electric ADU with no fuel-burning appliances and no attached garage may not strictly require CO alarms — but because many ADUs share a site with a garage or use combination smoke/CO devices, they are very commonly included. Verify your specific configuration with your building department.How it shows up on the plansOn our electrical plans, every required smoke and CO alarm is located on the floor plan with a symbol in the legend, and the general notes call out the interconnection, hardwiring, and battery-backup requirements per the applicable code edition. Missing or unlocated alarms is a routine plan-check correction we head off before submittal.Why garage conversions need special attentionConverting a garage into an ADU is one of the most common scenarios, and alarms are a frequent legalization correction because the original space was never built as living quarters. When the conversion creates a new sleeping room and removes the garage, the unit still needs full smoke-alarm coverage in and around the new bedroom and on each story. If the converted ADU is now attached to a remaining garage or contains any fuel-burning appliance, CO alarms come back into play. Older unpermitted conversions also commonly lack the interconnection and hardwiring that current code expects — all of which we resolve on the plan set up front.Requirements vary by jurisdiction and code cycle — placement, interconnection, and hardwiring rules can differ for new construction versus garage conversions and alterations. Confirm with your local building department.Smoke and CO alarm placement is included in every electrical set at no extra charge, and two revisions plus city corrections are part of every order. See how it works or order to begin.

Question 18

Do Electrical Plans include load calculations?

Accepted Answer

Yes — a formal NEC/CEC Article 220 load calculation is included in every one of our ADU Electrical Plan sets, at no additional charge. It is the engineering backbone of the set: panel amperage, the decision about whether your main service needs an upgrade, and your utility load letter all derive from it. California building departments require it as a submittal, and leaving it out is the single most common cause of electrical plan-check corrections.What the calculation totalsThe Article 220 calculation adds up every category of demand in the unit:General lighting and general-use receptacles: 3 VA per square foot of living area.Small-appliance circuits: 1,500 VA each, minimum two for the kitchen.Laundry circuit: 1,500 VA.Fixed appliances at nameplate rating: electric range/cooktop, water heater, dishwasher, disposal, microwave, and similar.HVAC: heat pump or air-conditioning load at rated amperage (generally the larger of heating vs. cooling).EV charger: included at full rated load — typically 40–50A for a Level 2 charger.Demand factors — why the panel can be smaller than the sumIf you simply added every load at full value, panels would be wildly oversized, because no household runs everything at once. Article 220 applies demand factors — code-specified percentages reflecting that loads don't all peak simultaneously. The chosen method (standard or optional) also affects the result. The final figure, in VA, is divided by the service voltage to yield the minimum amperage, which sets the panel size.How the load calc connects to the rest of the setIt justifies the panel schedule amperage and main breaker size.It feeds the single-line/riser diagram feeder and conductor sizing.It supports the utility load letter when you request a meter or service change.It documents whether the existing main service can carry the house plus the ADU, or whether a panel upgrade is required.Because the method involves specific code tables and judgment about which loads dominate, the calculation must be performed by a licensed electrician or MEP engineer — not estimated from square footage.For an all-electric 700 SF ADU with induction cooking, a heat pump water heater, mini-split HVAC, and a Level 2 charger, the calculated demand commonly lands in the range that justifies a 125A subpanel — but only the actual nameplate ratings and chosen method confirm it for your project.Why you can't skip it or copy oneOwners sometimes ask whether a neighbor's calc or a generic template will do — it won't. The Article 220 result depends on your exact square footage, your specific appliance nameplate ratings, your HVAC equipment, and your existing main-service loads, so it has to be run for your project. A missing or unsupported load calc is the most common reason an otherwise complete electrical submittal gets kicked back, which adds a correction cycle and weeks to your timeline. Including a clean, defensible calc up front is the least expensive insurance against that delay — and it doubles as the load letter your utility will ask for. Requirements vary by jurisdiction — confirm with your local building department. See the ADU electrical guide for a fuller walkthrough, or order a set from $995.

Question 19

What is included in Plumbing Plans?

Accepted Answer

Our ADU plumbing plans are a permit-ready drawing set that documents every part of your unit's water, waste, venting, and (where applicable) gas systems — everything a plan checker needs to approve the build and a plumber needs to install it correctly the first time.What the drawing set containsWater supply (potable) layout and sizing. Hot and cold distribution from the point of connection to every fixture, with pipe sizing based on the fixture-unit demand so the system delivers adequate pressure and flow under simultaneous use.Drain-Waste-Vent (DWV) plan. The full gravity drainage and venting network — branch drains at minimum 1/4 inch per foot slope, traps, and a code-compliant vent system — typically supported by a DWV isometric or riser diagram that shows how every fixture drains and vents in three dimensions.Plumbing fixture schedule. Each fixture listed with its make/model and CALGreen low-flow rating (1.28 gpf toilets, 1.8 GPM showerheads, 1.2 GPM lavatory faucets, 1.8 GPM kitchen faucets) so flow compliance is verifiable at a glance.Water heater details. Type (heat-pump, tankless, or tank), location, connections, and the seismic strapping detail required statewide.Sewer or septic connection point. The tie-in method, slope, and connection detail to your existing lateral, a new lateral, or an approved septic system.Gas piping plan and sizing with shutoffs and sediment traps — included whenever the design uses gas appliances (see the gas question below).Plumbing notes and details: CALGreen conservation notes, hot-water pipe insulation, backflow/cross-connection provisions where required, and general code references.How it fits the rest of your setThe plumbing sheets coordinate with your mechanical and electrical plans — for example, water-heating efficiency lines up with your Title 24 report, and condensate or recirculation pumps appear on the right trade's sheet. Most homeowners building a detached unit choose the Full MEP package so all three disciplines arrive together and consistent.DeliverableWhat it showsWater supply planHot/cold routing and pipe sizing to each fixtureDWV plan + isometricDrains, waste, vents, slopes, and trap/vent relationshipsFixture scheduleModels and CALGreen flow rates for every fixtureWater heater detailType, location, connections, seismic strappingSewer/septic detailConnection method and tie-in slopeGas plan (if used)Sizing, shutoffs, sediment trapsExact sheet requirements vary by jurisdiction and by your water/sewer district — confirm submittal expectations with your local building department.Single plans start from $995, and two revisions plus city corrections are always included. Start your order or see how it works.

Question 20

Does my ADU need a separate water meter?

Accepted Answer

Usually no — most California ADUs share the existing water meter and service with the main house, and state ADU law specifically discourages mandatory separate-meter requirements for attached ADUs and JADUs. That said, whether a separate meter is required, allowed, or simply worth installing depends entirely on your local water district, so confirm before you design.When a shared meter is fineFor the typical single ADU, the existing meter and service line can carry the added demand because CALGreen low-flow fixtures keep the new load modest. A complete ADU bathroom group plus a kitchen adds a defined fixture-unit count, and an existing 3/4-inch or 1-inch service serving a single-family home often has spare capacity. Sharing is simpler, cheaper, and the most common outcome.When a separate meter may be required or wiseDistrict policy. Some water districts require — or offer — a dedicated meter or sub-meter for a new dwelling unit, particularly for detached ADUs.Capacity limits. If the existing service is undersized for the combined demand, you may need a larger service or a second tap, which can trigger a meter.Separate billing. If you plan to rent the ADU and want the tenant billed directly for water, a separate meter or a private sub-meter makes that clean.Connection/capacity fees. A new meter usually carries a district connection fee that can range from modest to several thousand dollars plus the installation.How to decide — a quick checklistCall your water district and ask, in writing, whether a separate meter is required, optional, or prohibited for your ADU type.Confirm the existing service size and whether it can carry the added fixture-unit demand.Get the connection/capacity fee schedule so you can compare shared vs. separate on real numbers.Decide whether direct tenant billing matters to you — if so, weigh a separate meter or private sub-meter.Meter requirements and fees vary widely by jurisdiction and water district — and ADU law limits when separate connections can be mandated. Confirm with your local building department and water utility before finalizing design.Our plumbing plans document the water service point of connection and supply sizing either way, so your set reflects the path your district approves. See the ADU plumbing guide for the bigger picture on shared versus separate utilities.

Question 21

Can my ADU share plumbing with the main house?

Accepted Answer

Yes — in most cases an ADU can share both water supply and sewer with the main house, and for a single ADU this is the normal, code-compliant, and most economical approach. The unit still needs its own complete, independent fixtures; "sharing" refers to the service connections, not the bathroom.What sharing actually meansShared water supply: the ADU taps off the existing potable service rather than getting a new meter — provided the service has capacity for the combined demand.Shared sewer lateral: the ADU's drain ties into the home's existing building sewer through a wye or tee, as long as gravity slope (1/4 inch per foot) and lateral capacity allow.Shared gas, where used: the ADU can branch off the existing gas system if the meter and piping can carry the added BTU load.What you cannot share is the dwelling itself: to be a legal ADU the unit must have its own permanent provisions for cooking, bathing, and sanitation. A JADU is the one exception that may share a bathroom with the primary home.When sharing works well — and when it doesn'tFavors sharingFavors separate serviceADU close to existing lateral/meterDetached unit far from the connectionHealthy lateral with spare capacityOld clay/cast-iron lateral or marginal capacitySingle ADU, owner-billed utilitiesDistrict requires separate service per unitGravity slope achievable to tie-inDrains below sewer (ejector pump needed)Before you commit to sharingCamera the sewer lateral ($150–$350). A deteriorated line should be replaced before you add ADU load — far cheaper while trenches are open.Check fixture-unit and service capacity for both water and sewer with your districts.Confirm separate-service rules — some sewer/water districts require an independent lateral or meter for a new dwelling unit.Verify gravity slope to the tie-in; a downhill or below-grade unit may need a sewage ejector.Shared-versus-separate rules, capacity studies, and connection fees vary by city, water district, and sewer authority — confirm in writing with each during early planning.Our plumbing plans document the connection method, slope, and tie-in detail your plan checker needs, whether you share or run separate service. For a detached unit, pair them with the Full MEP package, or read the ADU plumbing guide for more.

Question 22

What water heater is best for an ADU?

Accepted Answer

For most new California ADUs the best choice is a heat-pump water heater, because it is highly efficient and aligns with the state's electrification direction. A tankless unit (gas or electric) is the strong runner-up where space is tight, and a standard tank heater still has its place. The "best" option ultimately depends on your fuel availability, space, hot-water demand, and Title 24 path.The main options comparedTypeBest forTrade-offsHeat-pump (HPWH)All-electric ADUs; lowest operating cost; favorable Title 24 creditNeeds adequate air volume/clearance, a condensate drain, and a dedicated 240V circuit; taller footprintTankless (gas or electric)Small units; endless hot water; wall-mounted to save floor spaceGas models need proper venting and gas sizing; electric models draw heavy amperageStandard tankLowest upfront cost; simplest installStandby losses; floor space; less favorable energy performanceHow to chooseCheck your city's fuel rules. Many California jurisdictions have all-electric ordinances for new construction, which point you to a heat-pump or electric option and can eliminate gas-line work entirely.Match capacity to demand. A studio or 1-bath ADU has modest hot-water needs; a 2-bath unit with simultaneous use benefits from a larger HPWH or a properly sized tankless.Mind the electrical load. Heat-pump and especially electric tankless units affect your panel sizing and load calculation — coordinate with your electrical plans.Plan placement for CALGreen. Locate the heater centrally so hot-water runs stay short and meet CALGreen delivery limits; a far-corner heater can force an added recirculation pump.What every ADU water heater needsRegardless of type, California requires seismic strapping — typically two metal straps lag-bolted into framing — plus listed connectors, a drip pan with drainage where it sits over finished space, and code-compliant venting for combustion units. These details belong on the plumbing sheet from the start.Fuel ordinances, rebates, and equipment requirements vary by jurisdiction and utility — confirm with your local building department before specifying a heater.Our plumbing plans note the water heater type, location, connections, and strapping, and the efficiency choice is coordinated with your mechanical plans and Title 24 report (a $240 add-on). See the ADU plumbing guide for a deeper comparison.

Question 23

Do Plumbing Plans include gas lines?

Accepted Answer

Yes — when your ADU design uses gas appliances, our plumbing plans include the gas piping plan with sizing, shutoff valves, and sediment traps. If the design is all-electric, there is no gas line to draw, and we coordinate the electric alternative across your mechanical and electrical sheets instead.What the gas portion showsPipe sizing for aggregate demand. The piping is sized to deliver the combined BTU/hr load of every gas appliance running at once while holding adequate pressure (commonly about 7 inches water column for standard residential appliances), based on total connected load, developed pipe length, and material.A manual shutoff valve at each appliance, accessible and within sight of the unit.A sediment trap (drip leg) ahead of each appliance gas valve to catch moisture and debris before it reaches the burner controls.Routing and connection points from the meter/branch to each appliance, with notes for the required pressure (leak) test before concealment.Common ADU gas loadsIf gas is used, the typical appliances are a tankless or tank water heater, a furnace or wall heater, a range/cooktop, and occasionally a gas dryer. Each adds to the BTU total the line must carry. Many California homeowners now go all-electric — a heat-pump water heater and heat-pump HVAC — which removes the gas line entirely and is often the cheaper, faster path, especially in cities with all-electric ordinances.What is on you vs. on the utilityOn the plans / your plumber: the piping layout, sizing, shutoffs, sediment traps, and pressure test shown on our sheets.On the gas utility (SoCalGas, PG&E, Southwest Gas): the meter and service connection. Added ADU load may require a meter upgrade or relocation — a separate application with its own timeline and fees, so start that early.All-electric ordinances, gas-infrastructure cost rules, and meter requirements vary by city and utility and continue to change — confirm current requirements with your local building department and gas provider.Whether your project is mixed-fuel or all-electric, our plumbing plans reflect the right approach, and the Full MEP package keeps gas, mechanical, and electrical decisions consistent. Start your order when you are ready.

Question 24

Do I need a Title 24 Report?

Accepted Answer

In almost every case, yes — if you are building a new ADU or converting existing space into a dwelling, California's energy code (Title 24, Part 6) applies, and the permit package needs a registered CF1R (Certificate of Compliance). The few exceptions are narrow and jurisdiction-specific, so the safest assumption for any ADU project is that a Title 24 report is required.Why an ADU triggers the requirementAn ADU is legally a dwelling unit — it has living, sleeping, cooking, and sanitation facilities — so it is treated like a residence for energy-code purposes, not like a shed or accessory structure. California's Building Energy Efficiency Standards apply to new dwelling units and to many alterations, which means the building department generally cannot issue your permit without the energy documentation in the submittal. The report is reviewed during plan check, alongside your architectural and MEP sheets, so it is a design-stage deliverable — needed before you submit, not produced during construction.Which projects need itProject typeTitle 24 report?Compliance pathNew detached ADUYes — alwaysNew construction (most comprehensive)New attached ADUYesNew construction for the added conditioned areaGarage / interior conversionYesAlteration rules (typically narrower)JADU (Junior ADU)Usually yesOften alteration; scope can be lighterCosmetic remodel onlyOften noNo energy systems changed — verify locallyA quick self-checkAre you adding new conditioned floor area? → Report needed.Are you converting an unconditioned space such as a garage or basement into living space? → Needed, under alteration rules.Are you installing or replacing HVAC, a water heater, or substantial lighting? → Likely needed.Is the work purely cosmetic — paint, flooring, cabinetry — with no energy systems touched? → Often not needed.What the report actually demonstratesThe CF1R is not a formality — it documents that your design meets minimum requirements across the building envelope (insulation R-values, window U-factor and SHGC), HVAC efficiency (heat pumps are the current prescriptive baseline for new construction), water heating (a heat-pump water heater baseline for most new dwelling units), high-efficacy LED lighting with required controls, and, where applicable, solar PV. You reach compliance through either the prescriptive path (every component meets a fixed minimum) or the performance path (energy modeling proves the whole building meets or beats a code baseline), and the chosen path is recorded in the report.One detail trips people up: the report must be registered with an approved data registry, not just printed from the compliance software. An unregistered PDF printout is frequently rejected at intake even when the numbers are correct.Because the edge cases (like-for-like swaps, very small JADU scopes) are sensitive to your jurisdiction, the applicable code cycle and local amendments vary — confirm with your local building department; the 2022 and 2025 code cycles are the ones most ADU owners deal with today, with the 2025 code applying to permit applications submitted on or after January 1, 2026. When a report is required, we prepare the registered CF1R as a +$240 Title 24 add-on alongside your MEP plans, so the energy documentation is ready at the same time as the rest of your permit set. See Title 24 Reports or review the full ADU Title 24 guide.

Question 25

What is the difference between MEP Plans and Title 24?

Accepted Answer

They are two different deliverables that answer two different questions. MEP plans show how the building's systems are physically built, routed, and permitted; the Title 24 report proves the building's design meets the energy-efficiency code. Both go into the same permit package, but they are reviewed by the plan checker as separate documents.MEP plans: how the systems are builtMEP stands for Mechanical, Electrical, and Plumbing. These are engineered construction drawings — the sheets your contractor builds from and the inspector checks against in the field. They include:Mechanical — HVAC equipment, ductwork or mini-split routing, and whole-dwelling ventilation (ASHRAE 62.2).Electrical — panel and load calculations, circuit layouts, outlet/lighting locations, and required GFCI/AFCI protection.Plumbing — water supply, drain-waste-vent (DWV), and fixture and water-heater locations.Title 24: proof the design is energy-compliantThe Title 24 report is not a construction drawing — it is a compliance document produced under Part 6 of the energy code, demonstrated through the registered CF1R (Certificate of Compliance). It evaluates the building envelope insulation, HVAC efficiency, water-heating type, high-efficacy LED lighting and controls, and any solar PV requirement, using either the prescriptive path (each component meets a fixed minimum) or the performance path (energy modeling shows the whole building meets or beats a code baseline).Side-by-sideMEP PlansTitle 24 ReportAnswersHow systems are built and routedWhether the design meets the energy codeFormatEngineered construction drawingsRegistered CF1R compliance documentUsed byContractor and field inspectorPlan checker (energy review)Verified later byField inspectionsCF2R (installer) and CF3R (HERS rater)Climate-zone driven?IndirectlyYes — one of 16 California climate zonesA concrete examplePicture an 800 SF detached ADU. The Title 24 report runs the energy model and concludes the design complies if it uses a ductless mini-split heat pump at a stated SEER2/HSPF2 efficiency, a heat-pump water heater, and high-efficacy LED lighting with vacancy sensors in the right rooms. Those conclusions are just numbers in a document until the MEP plans turn them into something buildable: the mechanical sheet specifies the exact mini-split make, model, and capacity sized from a Manual J load calculation; the plumbing sheet locates the heat-pump water heater with the air volume and condensate drainage it needs; and the electrical sheet shows the LED fixtures, the required controls, and the circuits feeding all of it. The report says what efficiency is required; the MEP plans say how to install equipment that delivers it.The two are interdependent: the CF1R sets the minimum HVAC efficiency, water-heater type, and lighting requirements, and the MEP plans must specify equipment that matches those numbers. When the equipment on the plans falls below what the CF1R assumed, the plan checker issues a correction.That interdependence is exactly why we prepare the Title 24 report as a +$240 add-on alongside your MEP plans — one team keeps the energy report and the construction sheets consistent. The applicable code cycle and local amendments vary — confirm with your local building department. See the Full MEP package, the Title 24 Reports page, or the complete ADU MEP guide.

Question 26

Can I bundle MEP Plans and Title 24?

Accepted Answer

Yes — and bundling is the recommended approach. The Title 24 report and your MEP plans are tightly interdependent, so producing them together as a coordinated set prevents the mismatches that are the single most common cause of energy-related plan-check corrections. We offer Title 24 as a +$240 add-on prepared alongside your MEP plans.Why bundling prevents correctionsThe registered CF1R sets the energy targets; the MEP plans have to deliver them. When the two are prepared by separate vendors, the equipment specified on the drawings frequently does not match the assumptions baked into the energy report. Bundling keeps them aligned across:HVAC — the CF1R establishes minimum heating/cooling efficiency, and the mechanical equipment schedule specifies equipment that meets it.Water heating — the CF1R fixes the water-heater type (often a heat-pump water heater) and efficiency, which the plumbing plans reflect.Lighting — high-efficacy LED fixtures and required controls noted in the CF1R appear on the electrical plans.Solar / storage — any PV requirement or exception, plus solar-ready and ESS-ready provisions, match between the report and the electrical sheets.What bundling gets youFewer corrections — the plan checker sees matching efficiency ratings and equipment on every sheet.Lower cost — the bundled CF1R is +$240, below the typical standalone Title 24 fee from many compliance providers.One timeline, one point of contact — no back-and-forth coordinating between separate companies, and both documents are ready for submittal at the same time.How it fits our pricingItemPriceSingle discipline (M, E, or P)from $995Two disciplinesfrom $1,195Full MEP packagefrom $1,495Title 24 report add-on+$240MEP pricing scales with ADU square footage. The standard 5-business-day turnaround is included; Priority (3 days) is +$299 and Expedited (1–2 days) is +$599. Two revisions plus city corrections are included, there is no sales tax, and we serve California only.What we need from you to bundleBundling is straightforward because both deliverables draw on the same project inputs. To prepare the coordinated set we need:Your finalized ADU floor plan and conditioned square footage (this scales the MEP pricing).The confirmed project address, which sets your climate zone and the applicable code cycle.The project type — new detached, new attached, or a garage/interior conversion — so the CF1R uses the correct new-construction or alteration path.Any equipment preferences you already have, which we reconcile against the energy targets.Add Title 24 at checkout and the energy report is prepared in lockstep with your MEP set — no scramble to retrofit compliance documentation after the fact.The applicable code cycle and local amendments vary — confirm with your local building department, and we'll align the CF1R to your jurisdiction. To get started, see the Full MEP package, review pricing and the cost of ADU MEP plans, or place your order.

Question 27

How long does a Title 24 Report take?

Accepted Answer

For a typical ADU, a registered Title 24 report (the CF1R) is prepared and registered within a few business days, and because we produce it alongside your MEP plans, it is ready on the same schedule as your MEP set — the standard 5-business-day turnaround — rather than adding a separate wait. Faster turnaround is available when your permit timeline is tight.What drives the timelineProject type. A garage conversion under alteration rules is generally simpler than a new detached ADU carrying full envelope, HVAC, water-heating, and potential solar requirements.Compliance path. A straightforward prescriptive design moves quickly; a performance-path model balancing trade-offs across the whole building takes more analysis.Information readiness. The biggest variable is having a finalized floor plan and a confirmed project address — the address sets your climate zone (one of 16) and the applicable code cycle, and changes to the layout after the report is built require it to be reworked.Registration. The CF1R must be registered with an approved data registry before submittal; an unregistered printout is frequently rejected at intake, so registration is part of the delivery, not an afterthought.Turnaround optionsService levelTimelineAdd-onStandard5 business daysIncludedPriority3 business days+$299Expedited1–2 business days+$599These turnaround tiers apply to the whole coordinated package, so choosing Priority or Express moves both your MEP plans and the Title 24 report onto the faster schedule together.Where it fits your permit timelineFinalize the ADU floor plan and confirm the project address (this fixes the climate zone and code cycle).We prepare the CF1R and the coordinated MEP plans together so equipment efficiencies match.You submit the registered CF1R with the full permit package.During construction, contractors complete the CF2R, and a HERS rater completes the CF3R where required.How to keep your schedule on trackThe fastest projects share a few habits. Lock the floor plan before the report is started — late layout changes are the most common cause of rework, because moving a wall, a window, or the water heater can change the energy model. Confirm the project address up front so the climate zone and code cycle are correct from the start. And decide your service level early: if your permit window is tight, Priority or Express moves the whole package, not just one piece.Preparing the report with the MEP plans is what keeps the timeline tight — there's no second vendor to wait on, and the energy report and construction sheets are consistent from day one.Keep in mind that the report's turnaround is separate from your city's review timeline — once submitted, plan check takes additional time, and some jurisdictions have extra intake steps. The applicable code cycle and local amendments vary — confirm with your local building department. The Title 24 report is a +$240 add-on delivered alongside your MEP set; see how it works, review pricing, or place an order.

Question 28

How much do MEP Plans cost?

Accepted Answer

ADU MEP plans start at $995 for a single discipline (Mechanical, Electrical, or Plumbing), $1,195 for any two disciplines, and $1,495 for the Full MEP Package (all three together) on an ADU up to 600 square feet. Pricing is flat and published, scales only by conditioned square footage, and carries no sales tax. We serve California only.Full pricing by square footageADU sizeSingle disciplineTwo disciplinesFull MEP PackageUp to 600 SF$995$1,195$1,495601–800 SF$1,295$1,495$1,795801–1,000 SF$1,695$1,895$2,1951,001–1,200 SF$2,095$2,295$2,595Traditional California engineering firms typically charge $2,500 to $6,500 for a complete residential ADU MEP set. Our flat pricing sits well below that range because we focus exclusively on California ADUs and standardize the engineering workflow.Bundle and saveThe Full MEP Package is always cheaper than ordering three separate single-discipline sets. At the same size, the Full MEP Package is $1,495 versus roughly $2,985 for three separate singles — a savings of nearly $1,490, and the gap widens as the ADU grows. Bundling also keeps the disciplines coordinated, which prevents the cross-discipline conflicts that cause plan-check corrections.Optional add-onsAdd-onPriceTitle 24 energy report+$240Standard turnaround (5 business days)Included ($0)Priority turnaround (3 business days)+$299Expedited (1–2 business days)+$599What is included at no extra chargePermit-ready PDF delivery formatted for California building departments.Two rounds of revisions so you can refine the design without surprise fees.City plan-check corrections related to our MEP plans — we revise and resubmit until your permit is issued.For example, an all-electric 750 SF ADU needing the Full MEP Package with a Title 24 report is $1,795 + $240 = $2,035 on standard turnaround. A compact 550 SF studio needing only electrical plans is just $995. To see your exact tier, visit the pricing page or start an order, and review how it works first.

Question 29

What is included in the price?

Accepted Answer

Every order includes the finished, permit-ready MEP plans delivered as a PDF, two rounds of revisions, and city plan-check corrections related to our drawings — at no extra charge, with no sales tax. The published price is the price you pay; the only optional extras are a Title 24 report and faster turnaround.Included at no extra chargeIncludedWhat it meansPermit-ready PDF deliveryDrawings formatted and ready to submit to your California building department.Two rounds of revisionsRefine the design twice without any added fee.City correctionsIf plan check returns comments on our MEP plans, we revise and resubmit until your permit is issued.No sales taxPlan services are not taxed, and pricing is identical statewide.Standard 5-business-day turnaroundIncluded at $0 from receipt of complete project information.What each discipline's plans containDepending on what you order, the deliverable includes the engineering, calculations, schedules, and code-compliant drawings for that discipline:Mechanical: Manual J load calculation, HVAC layout and equipment schedule, and ASHRAE 62.2 / Title 24 ventilation.Electrical: panel and load calculations, power and lighting plans, circuit design with GFCI/AFCI protection, single-line diagram, and panel schedule.Plumbing: water supply design, drain-waste-vent layout, water heater specification, fixture schedule, and riser/isometric diagrams.Optional extras (not automatically included)Optional add-onPriceTitle 24 energy report+$240Priority turnaround (3 business days)+$299Expedited (1–2 business days)+$599Additional revisions beyond the first two$150 eachWhat is not in our scopeSo nothing surprises you, the following are billed by third parties and are not part of the plan price: architectural design changes, structural engineering, city/permit and plan-check fees, school/impact fees, utility connection fees, site visits, HERS field verification testing, and contractor installation work. See our FAQ and the cost of ADU MEP plans for the full breakdown.For example, a 650 SF ADU ordering two disciplines plus Title 24 pays $1,495 + $240 = $1,735, which covers the plans, two revisions, city corrections, and the energy report — full stop. Ready to begin? Visit the pricing page or place your order.

Question 30

Are city corrections included?

Accepted Answer

Yes. If your city's plan check returns corrections related to our MEP plans, we revise the drawings and resubmit at no additional charge — until your permit is issued. This is included in every order, not an upsell, and it sits on top of the two rounds of revisions you also receive.How the correction process worksYou submit our permit-ready plans to your California building department.If plan check returns comments on our MEP scope, send us the correction letter.We revise the affected drawings to address each comment.You resubmit the corrected set. We repeat this until the permit is issued — there is no cap on correction cycles for our own scope.What is covered vs. what is separateCovered at no chargeSeparate / not our scopeCorrections to our mechanical, electrical, or plumbing drawingsCity permit and plan-check fees themselvesCode-citation fixes on our MEP sheetsArchitectural or structural corrections (other consultants)Re-coordination between our own disciplinesResubmittal fees the city may chargeResubmittal-ready revised PDFsChanges you request that alter the original design scopeWhy corrections are rare with a coordinated setMost MEP plan-check comments come from cross-discipline mismatches — an electrical panel that doesn't feed the right water-heater load, ventilation that doesn't match the energy report, or a plumbing fixture with no power shown. When one team prepares the Full MEP Package, those conflicts are caught before submittal. Adding a Title 24 report (+$240) keeps equipment efficiencies aligned across every sheet, which is the single most effective way to clear review on the first pass.Note: "city corrections included" means corrections to our drawings. If a building department requests a genuine design change driven by your architect, the structural engineer, or a new owner request, that may fall outside the original MEP scope and would be handled as a revision (the first two are free; additional revisions are $150 each).For example, if a plan checker asks us to add an EV-ready conduit note or upsize a vent, we revise and return the corrected sheets at no cost, as many times as needed, until you have your permit. Learn more in how it works, or start an order.

Question 31

How many revisions are included?

Accepted Answer

Two rounds of revisions are included free with every order, so you can refine the design after the first draft without any added cost. Beyond those two, additional revisions are a flat $150 each. Separately — and this does not count against your two revisions — city plan-check corrections to our MEP plans are always free until your permit is issued.Revisions vs. city correctionsIncluded revisionsCity correctionsWhat triggers itYou request a design changePlan check returns comments on our plansHow many freeTwo roundsUnlimited until permit issuesCost after that$150 per additional revision$0 (our scope)What counts as a revisionA revision is a change you ask for after we deliver the plans — for example:Relocating the electrical panel or adding receptacles.Swapping a tankless water heater for a heat pump water heater.Moving a mini-split head or changing the ventilation approach.Adjusting fixture locations after an architectural tweak.How to make the two free rounds countFinalize your architectural floor plan before we start, so layouts don't shift mid-design.Confirm appliances and equipment preferences up front (all-electric vs. gas, water heater type).Bundle your edits into one consolidated round rather than sending changes piecemeal.Most ADU projects never use the second revision, let alone a paid third. Because we deliver a coordinated MEP set, the disciplines already agree with one another, so the typical "revision" is a small owner preference rather than a fix.Example: A homeowner receives the Full MEP set, then asks to move the laundry and add a bathroom exhaust fan (round 1), and later relocates the subpanel (round 2). Both rounds are free. If they then decide to redesign the kitchen layout entirely (round 3), that revision is $150. Meanwhile, any correction the city raises on those same plans is still handled at no charge.Questions about scope? See our FAQ and how it works, or start your order.

Question 32

Are there hidden fees?

Accepted Answer

No. Our plan price is flat and published, and it already includes two revisions, city corrections, and permit-ready PDF delivery — with no sales tax in California. The only charges from us are optional, opt-in add-ons. That said, building an ADU involves third-party fees that are outside our scope, and we list them openly here so nothing surprises you.What is always included in our pricePermit-ready PDF deliveryTwo rounds of revisionsCity plan-check corrections on our MEP plans until permit issuanceNo sales tax; identical pricing statewideStandard 5-business-day turnaround at $0Optional charges from us (only if you choose them)Optional add-onPriceTitle 24 energy report+$240Priority turnaround (3 business days)+$299Expedited (1–2 business days)+$599Additional revisions beyond the first two$150 eachThird-party fees that are NOT part of our scopeThese are billed by the city, your utility, or other consultants and contractors — not by us. They vary widely by jurisdiction and project:City permit and plan-check fees charged by your building department.School and impact/development fees (many ADUs under 750 SF are exempt under state law).Utility connection fees for water, sewer, gas, and electric — water and sewer in particular can run into the thousands.Architectural design changes and structural engineering — we prepare MEP only.HERS field verification testing by an independent certified rater, where the energy design requires it.Site visits and contractor installation work — equipment, labor, slab cutting, service upgrades, and similar items are contractor scope.Think of it this way: we provide the permit-ready MEP plans for one transparent fee. The city, the utilities, your contractor, and (when required) a HERS rater each charge their own fees that are outside our control. We call these out up front so you can budget the whole project accurately.For example, a 600 SF Full MEP order is $1,495 with nothing hidden added — if you opt into Title 24 it becomes $1,735, and your city's permit fee (billed by them) is separate. For the full picture, read the cost of ADU MEP plans and the complete ADU MEP guide, then see the pricing page or place your order.

Question 33

How much does rush service cost?

Accepted Answer

Standard turnaround is 5 business days and is included at no charge ($0). If you need plans faster, Priority delivery (3 business days) is +$299 and Expedited delivery (1–2 business days) is +$599. These are flat fees at any ADU size and any discipline count.Turnaround options at a glanceOptionDeliveryPriceStandard5 business daysIncluded ($0)Priority3 business days+$299Expedited1–2 business days+$599The turnaround clock starts when we have your complete project information — finalized architectural floor plans, equipment preferences, and ADU details. Expedited speeds up our production time; it does not change how long your city takes to review the permit.How rush combines with the plan priceThe rush fee is added on top of your plan price and any Title 24 add-on. A few worked examples:OrderMathTotal600 SF single discipline, Express$995 + $599$1,394750 SF Full MEP, Priority$1,795 + $299$1,994600 SF Full MEP + Title 24, Express$1,495 + $240 + $599$2,134Do you actually need rush?Most projects are well served by the included 5-business-day standard option — permit timelines at the city are usually the longer pole in the tent. Consider Priority or Express when:You are racing a permit-submittal deadline or a contractor's start date.An appraisal, financing, or sale milestone depends on plans in hand.You discovered the MEP requirement late and need to catch up.Expedited affects only our production speed and quality is unchanged — every rushed set still includes two revisions, city corrections, and permit-ready PDF delivery, all with no sales tax. Expedited does not waive or alter any included benefit.You can select your turnaround at checkout. Compare options on the pricing page, see how it works, or start your order.

Question 34

How does ordering work?

Accepted Answer

Ordering is a guided three-step online flow at order.html: you choose your plans and turnaround, tell us about your project, and check out securely. The whole thing takes a few minutes, and you don't need to have every technical answer ready to start.The three stepsPlans. Choose your plan type &mdash; a Single discipline (Mechanical, Electrical, or Plumbing), any Two disciplines, or the Full MEP Package &mdash; then pick the ADU size tier that matches your project (Up to 600 SF, 601&ndash;800, 801&ndash;1,000, or 1,001&ndash;1,200 SF). You can optionally add a Title 24 report for $240, and select your turnaround. The order summary calculates your exact price as you go.Details. Enter the project address (we use it to confirm your California climate zone and local code requirements), your contact information, who you are (homeowner, contractor, architect, designer, and so on), the project type (Detached ADU, Attached ADU, Garage Conversion, JADU, or Addition), the project status, and a short scope of work.Checkout. Review the order recap &mdash; plan, disciplines, size, Title 24, and turnaround &mdash; and pay securely via Stripe (256-bit SSL; no card data is stored).Choosing your turnaroundEvery order includes Standard turnaround at no extra cost; faster options are available when you have a deadline:OptionTimelineCostStandard5 business daysIncludedPriority3 business days+$299Expedited1&ndash;2 business days+$599The turnaround clock starts when we have your complete plans and project details &mdash; not the moment you click pay &mdash; so gathering your files in advance keeps things moving.Sending us your filesTo prepare your plans we work from your architectural drawings &mdash; the floor plan, site plan, and elevations (a full architectural set is ideal). You can upload them right at checkout, or email them to orders@mepplansusa.com afterward. Either way works, and choosing to email later does not delay your order, because the turnaround clock only begins once your complete information reaches us. PDF or common CAD formats are both accepted, and a single combined architectural PDF covers everything we need. If you don't have architectural plans yet, you can still order &mdash; we begin once your drawings are ready and can advise exactly what to provide.What's included in every orderCoordinated, permit-ready MEP drawings delivered as a PDF by email.Two revisions.City corrections related to our MEP plans &mdash; if plan check returns MEP corrections, we revise and resubmit at no charge until the permit is issued.No California sales tax.Architectural design changes, structural engineering, permit and utility fees, site visits, HERS/field testing, and contractor installation are not included. For a step-by-step walkthrough, see how it works, or head straight to order.html when you're ready to begin.

Question 35

What files do I need to upload?

Accepted Answer

To prepare your MEP plans, we work from your architectural drawings &mdash; ideally a full architectural set, but at minimum the architectural floor plan, the site plan, and the elevations. You can upload these at checkout or email them to orders@mepplansusa.com afterward.The core files we needArchitectural floor plan &mdash; shows room layout, wall locations, kitchen and bathroom positions, doors and windows. This is the single most important document; our engineers lay out circuits, ductwork, and plumbing directly onto it.Site plan &mdash; shows where the ADU sits on the property, setbacks, and the location of existing structures and utilities. It informs sewer/water tie-ins, the electrical feeder route, and outdoor equipment placement.Elevations &mdash; exterior views that confirm ceiling heights, roof form, and where wall-mounted or rooftop equipment can go.A complete architectural set is ideal because it lets us coordinate the MEP plans cleanly with your design the first time and reduces the chance of plan check corrections.Accepted formatsWe accept PDF or common CAD formats. PDFs are the most common and work perfectly well &mdash; you do not need to provide editable CAD files. If your architect or designer gave you a single combined PDF that already contains the floor plan, site plan, and elevations, that one file covers everything.What we do with each fileIt helps to understand why each drawing matters, so you can tell whether what you have is enough:For the electrical plans, we use your floor plan to place receptacles, switches, lighting, smoke and CO detectors, the panel or subpanel, and EV-charger conduit &mdash; all positioned relative to your actual room and wall layout.For the mechanical plans, we use the floor plan and elevations to locate HVAC equipment, route any ductwork, size the system to the conditioned area, and place ventilation, range hood, and bath fans.For the plumbing plans, we use the floor plan and site plan to lay out fixtures, drain/waste/vent runs, the water heater, and the sewer and water tie-ins to existing utilities.If a drawing is missing, we may not be able to complete the corresponding discipline cleanly &mdash; which is why the complete set keeps your project moving without back-and-forth.A quick pre-order checklistLocate your architectural floor plan, site plan, and elevations (or the combined architectural PDF).Confirm the files are legible and to scale &mdash; final, not rough sketches where possible.Note any special requirements in the scope-of-work field: panel upgrade, EV charger, all-electric design, specific appliances, or a city correction response.Have your project address ready so we can confirm your climate zone and local code.Helpful extras (optional)If you have them, these speed things up but are not required to order:Structural plans, if already prepared.A list of city plan check comments, if you're responding to corrections.Your existing electrical panel size, if known.You don't need to assemble everything perfectly before starting &mdash; you can place your order now and send files as they're ready. The turnaround clock simply begins once we have the complete information. When you're set, begin at order.html, or review the full process on how it works.

Question 36

What if I do not have architectural plans yet?

Accepted Answer

You can still place your order. We begin preparing your MEP plans once your architectural drawings are ready, and in the meantime we can advise exactly what we'll need from you. Ordering early simply reserves your spot in our queue.Why we need architectural plans firstMEP plans are not standalone documents &mdash; they are engineered on top of your architectural floor plan. Our engineers place outlets, switches, light fixtures, ductwork, HVAC equipment, plumbing fixtures, drain and vent lines, and panel locations directly in relation to your walls, rooms, kitchen, and bathrooms. Without a finalized floor plan, there's nothing to coordinate those systems against. That's why the turnaround clock starts on receipt of your complete architectural information.What we do and don't provideAn important distinction: we prepare MEP plans and Title 24 &mdash; not architectural design. We don't draw the floor plan, elevations, or site plan themselves. If you don't yet have those, you'll need an architect or designer to produce them first. Once you do, we take it from there.Your options if you're not ready yetOrder now, send plans later. Complete checkout to lock in your pricing and turnaround tier, then email your architectural set to orders@mepplansusa.com when your designer delivers it. Your order is not penalized for the wait &mdash; the clock only starts once we have complete information.Wait until plans are done. If you prefer, you can hold off and order once your architectural drawings are finalized, so your MEP plans can move immediately into production.Reach out for guidance. If you're unsure what counts as a "complete" set or which drawings we need, contact us before ordering and we'll tell you precisely what to ask your designer for.What to ask your architect or designer forA scaled architectural floor plan with room dimensions and fixture locations.A site plan showing the ADU's position, setbacks, and existing structures.Elevations confirming ceiling heights and roof form.If available, a single combined architectural PDF containing all of the above.You set the project type as "Plans In Progress" or "Starting From Scratch" during checkout, so we know to expect your drawings shortly and can plan accordingly.Should you order now or wait?There's no wrong choice, but here's how to decide. If your architectural drawings are close to finished and you want to lock in your pricing and turnaround tier, ordering now is a fine move &mdash; you simply email the set when it arrives. If your design is still early or likely to change significantly, it may be easier to wait until the floor plan is settled, since meaningful layout changes after we've started can consume one of your included revisions. Either way, the key point holds: we never begin engineering until your architectural plans are ready, so you're never charged for work that can't yet be done correctly, and your turnaround time always measures from complete information.When your architectural set is in hand, we deliver coordinated, permit-ready MEP drawings ready to submit to your building department. See how it works for the full sequence, or start your order at order.html.

Question 37

Can I email my plans later?

Accepted Answer

Yes. You can upload your files at checkout, or simply email them to orders@mepplansusa.com after you order. Your order is not delayed for choosing to send files later &mdash; the turnaround clock starts when we receive your complete plans and project details, however you get them to us.Two ways to send your filesUpload at checkout. The most direct path &mdash; attach your architectural floor plan, site plan, and elevations as you place the order so everything arrives together.Email afterward. If your files aren't handy at the moment of checkout, complete your order anyway and email them to orders@mepplansusa.com whenever they're ready. This is perfectly normal and common, especially when an architect is still finalizing the set.How the turnaround clock actually worksThis is the key reassurance: your turnaround does not begin counting the instant you pay. It begins once we have everything we need to start &mdash; your complete architectural plans and your project details. So whether you upload at checkout or email a day or two later, you lose no production time as long as you get the files to us. The Standard 5 business days, Priority 3 business days, or Express 1&ndash;2 business days all measure from that starting point.Why this flexibility helpsMany ADU projects are still in motion when an owner is ready to commit. Your architect may be finalizing the set, you may be waiting on a revised floor plan, or you may simply not have the files in front of you the moment you sit down to order. Letting you email plans afterward means you can secure your plan choice, size tier, turnaround, and price first &mdash; then send drawings on your own schedule without losing your place or paying more. Contractors and designers managing several projects at once find this especially convenient, since they can place the order and forward the architectural set from the client separately.Tips for emailing your plansUse the same email address and name you entered at checkout, or reference your project address, so we can match the files to your order quickly.Send PDF or common CAD formats &mdash; a combined architectural PDF is ideal.Include the full set in one message where possible (floor plan, site plan, elevations) so nothing is missing when we begin.Mention any special requirements &mdash; panel upgrade, EV charger, all-electric design, or city correction comments &mdash; if you didn't already note them in the scope-of-work field.If you're missing one drawing, send what you have and tell us what's coming. We'll let you know if anything is needed before we can start.Sending files later is a flexible, no-penalty part of the process &mdash; designed so you can secure your order and pricing first and finalize documents on your own schedule. When you're ready, begin at order.html or review the full flow on how it works.

Question 38

How will my plans be delivered?

Accepted Answer

Your finished plans are delivered as a permit-ready PDF by email &mdash; ready to submit directly to your building department. There's no waiting for a physical package; everything arrives digitally.What you receiveYou get a complete, coordinated MEP plan set covering the disciplines you ordered. A full set includes labeled sheets &mdash; mechanical (M-1, M-2), electrical (E-1, E-2), and plumbing (P-1, P-2) &mdash; with equipment schedules, load and heat load calculations, required code notations, and a cover sheet referencing the applicable California codes. If you added a Title 24 report, the energy compliance documentation is coordinated with the plans so the two agree, which heads off one of the most common sources of plan check corrections.Why PDF, and how to submit itPDF is the format California building departments expect. The deliverable is formatted for permit submittal and works with the electronic plan review portals California cities use (such as ePlanLA and similar systems), and it can be printed at any large-format print shop if your jurisdiction requires physical sheets. In short, the same file works whether your city accepts digital uploads or asks for printed plans.How long until you receive itDelivery timing follows the turnaround you selected at checkout, measured from when we have your complete plans and project details:TurnaroundDeliveryStandard (included)5 business daysPriority (+$299)3 business daysExpedited (+$599)1&ndash;2 business daysBecause the clock starts on receipt of complete information rather than at payment, sending your full architectural set up front is the surest way to get your PDF on the timeline you paid for. See pricing for how turnaround options factor into your total.What happens after deliverySubmit to your building department &mdash; upload or print the PDF and file it with the rest of your permit application (architectural, structural, and Title 24 documents).Two revisions included &mdash; if you need adjustments after reviewing the plans, two revisions come with your order.City corrections included &mdash; if plan check returns corrections related to our MEP plans, we revise and resubmit at no additional charge until the permit is issued.A few practical notesDelivery goes to the email address you entered at checkout, so make sure it's correct &mdash; the order form asks you to confirm it twice for this reason.Check your spam or promotions folder if you don't see the delivery email, and add orders@mepplansusa.com to your contacts.Keep the original PDF; it's the file you'll resubmit if the city requests any changes.Final plans are delivered electronically &mdash; no shipping, no delay, and ready to submit the moment they land in your inbox.To see how delivery fits into the overall process, visit how it works, or start your order at order.html.

Question 39

What happens after I order?

Accepted Answer

Once you've checked out, our engineering team gets to work preparing coordinated, permit-ready MEP drawings for your ADU. You'll receive your finished plans as a PDF by email, with two revisions and city corrections included &mdash; here's the full sequence so you know exactly what to expect.Step by step after checkoutWe confirm we have what we need. Your turnaround clock starts once we have your complete architectural plans (floor plan, site plan, elevations) and project details. If anything is missing, we'll reach out so production isn't held up unexpectedly.Our engineers prepare your plans. We design your mechanical, electrical, and plumbing systems and coordinate them against your architectural drawings &mdash; load and heat load calculations, equipment schedules, panel schedules, ductwork, plumbing routing, and all required California code notations. If you added Title 24, it's coordinated with the plans from the start.We deliver your PDF. Your permit-ready plan set arrives by email within your chosen turnaround &mdash; Standard 5 business days, Priority 3, or Express 1&ndash;2 &mdash; measured from when we had complete information.You submit to your building department. File the PDF with your permit application.We handle revisions and corrections. Two revisions are included, and if plan check returns MEP corrections, we revise and resubmit at no charge until the permit is issued.What you can do while we workOnce your order is in production there's nothing you need to actively manage, but a little preparation makes the rest of permitting smoother:Confirm your other permit documents are progressing &mdash; architectural, structural, and the rest of your application package &mdash; so everything can be submitted together.Start any utility coordination early if your project involves a panel upgrade or new service or water/sewer connection, since utility timelines run separately from plan preparation.Keep an eye on the inbox you used at checkout in case we need a clarification on scope.What's includedCoordinated, permit-ready MEP drawings delivered as a PDF.Two revisions.City corrections related to our MEP plans &mdash; revised and resubmitted at no charge until the permit is issued.No California sales tax.What's not includedArchitectural design changes and structural engineering.Permit and city fees, and utility fees.Site visits and HERS / field verification testing.Contractor installation work.The corrections promise, in plain termsPlan check corrections are a normal part of permitting, not a rejection. If the city's review returns corrections related to our MEP plans, we address them, revise the drawings, and resubmit &mdash; at no additional charge &mdash; until your permit is issued.That coverage is one of the most valuable parts of ordering with us: you're not on your own once the plans are delivered. For the complete walkthrough see how it works, compare options on pricing, or start now at order.html.

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