Question 1

How much do ADU MEP Plans cost?

Accepted Answer

Answer coming soon.

Question 2

Why do MEP prices change by square footage?

Accepted Answer

MEP pricing scales with square footage because a larger ADU contains more fixtures, more circuits, higher mechanical loads, and longer pipe and duct runs — and each of those requires additional engineering, drafting, and calculation work. The price reflects the real design effort, not an arbitrary surcharge.What actually grows as the ADU gets biggerMechanical: a larger conditioned area means a higher heating and cooling load. The Manual J load calculation must account for more wall, window, and roof area, and the equipment may need to be upsized or split into multiple zones. ASHRAE 62.2 ventilation rates also rise with floor area and bedroom count.Electrical: more rooms and appliances mean more branch circuits, additional receptacles to meet spacing requirements, more lighting, larger panel/load calculations, and frequently a larger subpanel and feeder.Plumbing: bigger units add fixtures (extra bathroom, laundry, larger kitchen), which means more supply and drain-waste-vent piping, longer runs, additional venting, and more detailed isometric and riser diagrams.How the tiers map to engineering effortADU sizeTypical layoutFull MEP priceUp to 600 SFStudio / 1 bath, single zone$1,495601–800 SF1 BR / 1 bath$1,795801–1,000 SF2 BR / 1–2 bath$2,1951,001–1,200 SF2 BR / 2 bath, more fixtures and circuits$2,595The same logic applies to single-discipline and two-discipline orders — each tier steps up because the sheet count, schedules, and calculations grow with the unit.Why size-based tiers are fairer than one flat feeA single flat price would force owners of small studios to subsidize the engineering of large two-bedroom units. Tiering by square footage means a 550 SF backyard studio pays for a studio's worth of work, and a 1,150 SF family ADU pays for the additional fixtures and loads it actually requires.This is why we publish the brackets openly rather than quoting case by case — you can verify exactly which tier your project falls into before you order.What does not change with sizeOur included benefits are flat regardless of square footage: two revisions, city corrections, and permit-ready PDF delivery. The Title 24 report add-on is a flat +$240 at any size, and turnaround upgrades are flat fees as well.To find your bracket, measure the conditioned floor area and check the pricing page, then place your order.

Question 3

Is Full MEP cheaper than ordering disciplines separately?

Accepted Answer

Yes. The Full MEP Package is substantially cheaper than ordering Mechanical, Electrical, and Plumbing as three separate single-discipline plan sets — at the same square footage you save roughly $1,490 by bundling.Bundle vs. three separate singlesADU sizeThree singles, separatelyFull MEP PackageYou saveUp to 600 SF$2,985$1,495$1,490601–800 SF$3,885$1,795$2,090801–1,000 SF$5,085$2,195$2,8901,001–1,200 SF$6,285$2,595$3,690The "three singles" column is simply the single-discipline rate (for example $995 at up to 600 SF) multiplied by three. Because the package is priced as one coordinated job rather than three independent ones, the savings grow as the ADU gets larger.Why the bundle costs less to produceShared project setup: we build one set of base drawings, one equipment understanding, and one Title 24 alignment instead of repeating intake and coordination three times.Built-in coordination: when the same team draws mechanical, electrical, and plumbing together, the panel feeds the right loads, the water heater circuit matches the plumbing, and ventilation matches the energy report — which prevents the cross-discipline conflicts that cause plan-check corrections.One submittal: a single coordinated MEP set is easier for the city to review than three disconnected sets.When a single or two-discipline order makes senseBundling is the best value for most new-construction ADUs, but not every project needs all three. Choose individual disciplines when:An attached ADU or addition ties into existing house systems and only needs, say, electrical and mechanical.A garage conversion already has adequate plumbing but needs new wiring and HVAC.Your architect or another engineer is handling one discipline.For those cases, the two-discipline tier ($1,195 and up) still beats buying two separate singles, and a lone discipline starts at $995. See mechanical, electrical, and plumbing pages for what each covers.The bundle also reduces review riskBeyond the dollar savings, a coordinated set lowers the odds of a plan-check correction. Most MEP comments at the city stem from cross-discipline mismatches — the electrical panel not feeding the right water-heater load, ventilation not matching the energy report, or a fixture on the plumbing plan with no power shown. When one team draws all three, those conflicts are caught before submittal rather than after. Adding the Title 24 report (+$240) to a Full MEP order keeps equipment efficiencies aligned across every sheet, which is the single most effective way to clear review on the first pass.Note: the comparison above is for our plan-preparation fees only. City permit fees, utility connection fees, and field testing are separate and unaffected by which package you choose.Ready to bundle and save? Review the Full MEP Package or go straight to order.

Question 4

How much do Mechanical Plans cost?

Accepted Answer

Standalone ADU mechanical plans start at $995 for an ADU up to 600 SF and scale to $2,095 for 1,001–1,200 SF. Mechanical can also be combined with another discipline starting at $1,195, or included in the Full MEP Package starting at $1,495.Mechanical plan pricing by sizeADU sizeMechanical onlyWith one more disciplineFull MEP (all three)Up 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$2,595What the mechanical fee coversManual J heat load calculation sizing heating and cooling capacity to your ADU's square footage, windows, insulation, and California climate zone.HVAC system design and layout — typically a ductless mini-split heat pump, with equipment location and any ducting shown.Equipment schedule listing make, model, capacity (BTU/hr), and efficiency ratings that meet current Title 24 minimums.Ventilation design per ASHRAE 62.2 and Title 24, including bathroom exhaust fans, kitchen exhaust, and condensate drainage.Why mechanical scales with square footageA larger conditioned area carries a higher heating and cooling load, may require upsized or multi-zone equipment, and demands higher ASHRAE 62.2 ventilation rates. More area means more calculation and drafting work, which is why each size bracket steps up.Common pairings and add-onsMechanical is frequently ordered with the Title 24 energy report (+$240), because HVAC efficiency values on the plans must match the energy model exactly. Ordering both from one team eliminates the most common mechanical correction. Turnaround upgrades are available: Priority (3 business days) +$299 or Expedited (1–2 business days) +$599; standard 5-business-day turnaround is included.What is not includedOur fee covers the plans only. The physical equipment, installation labor, city permit fees, and HERS field verification of refrigerant charge or fan watt draw (where applicable) are billed separately by suppliers, contractors, the city, and a HERS rater.How to know which tier you are inUse the conditioned floor area of the ADU — the heated and cooled living space — to pick your bracket. A backyard studio at 540 SF is the $995 tier; a one-bedroom at 720 SF is the $1,295 tier. If your unit sits right at a bracket boundary, the published table removes any guesswork, and we confirm the size at order intake so the price you see is the price you pay. There is no sales tax on the plan service and pricing is identical anywhere in California.Every mechanical order includes two revisions, city corrections, and permit-ready PDF delivery. See the pricing page or start your order.

Question 5

How much do Electrical Plans cost?

Accepted Answer

Standalone ADU electrical plans start at $995 for an ADU up to 600 SF and scale to $2,095 for 1,001–1,200 SF. Electrical can be paired with another discipline from $1,195, or bundled into the Full MEP Package from $1,495.Electrical plan pricing by sizeADU sizeElectrical onlyWith one more disciplineFull MEP (all three)Up 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$2,595What the electrical fee coversPanel and load calculations sizing the subpanel and feeder for an all-electric ADU (commonly 100–125 amps).Power and lighting plans with receptacle spacing, switching, and fixtures per California Electrical Code.Circuit design with required GFCI and AFCI protection noted, plus dedicated appliance circuits.EV-ready infrastructure — conduit pathway and reserved breaker — as required by Title 24, a frequent correction item when omitted.Single-line diagram and panel schedule for plan-check review.Why electrical scales with square footageA bigger ADU has more rooms and appliances, which means more branch circuits, additional receptacles to meet code spacing, more lighting, and a larger panel and load calculation. Each added circuit and device is more to design and draft, so the price steps up per bracket.Add-ons and turnaroundWhile electrical plans do not themselves require a Title 24 report, many owners add the Title 24 energy report (+$240) so lighting power density and EV/electrification requirements are documented consistently across the project — especially when bundling with mechanical. Turnaround upgrades: Priority +$299 (3 business days), Expedited +$599 (1–2 business days); standard 5-business-day delivery is included.What is not includedOur fee covers the drawings only. Panel hardware, wiring, the electrician's labor, utility electric service/connection fees, and city permit fees are separate.Electrical bundled vs. standaloneIf your ADU also needs mechanical and plumbing, the Full MEP Package is the better value: at up to 600 SF it is $1,495 versus $2,985 for three separate singles. Electrical pairs especially well with mechanical, since the heat-pump and water-heater loads on the panel schedule come directly from those disciplines — ordering them together keeps the load calculation accurate. Standalone electrical makes sense mainly for garage conversions or attached additions where plumbing and HVAC tie into the existing house.Every electrical order includes two revisions, city corrections, and permit-ready PDF delivery, with no sales tax. View the pricing page or begin an order.

Question 6

How much do Plumbing Plans cost?

Accepted Answer

Standalone ADU plumbing plans start at $995 for an ADU up to 600 SF and scale to $2,095 for 1,001–1,200 SF. Plumbing can be combined with another discipline from $1,195, or included in the Full MEP Package from $1,495.Plumbing plan pricing by sizeADU sizePlumbing onlyWith one more disciplineFull MEP (all three)Up 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$2,595What the plumbing fee coversWater supply design — hot and cold distribution, pipe sizing, and fixture connections.Drain-waste-vent (DWV) layout with proper venting, slopes, and cleanouts per the California Plumbing Code.Water heater specification — typically a heat pump water heater or tankless unit sized to demand and Title 24 efficiency requirements.Fixture schedule and riser/isometric diagrams for kitchen, bathroom(s), and laundry.Gas piping where gas appliances are used, sized to BTU demand.Why plumbing scales with square footageLarger ADUs add fixtures — a second bathroom, a bigger kitchen, a laundry — and each fixture adds supply lines, drain and vent piping, and longer runs. More fixtures and longer runs mean more sizing calculations and more detailed riser and isometric drawings, which is reflected in each price bracket.Add-ons and turnaroundThe water heater on your plumbing plans must match the efficiency assumptions in your energy model, so pairing plumbing with the Title 24 report (+$240) keeps the two consistent. Turnaround upgrades are Priority +$299 (3 business days) or Expedited +$599 (1–2 business days); standard 5-business-day delivery is included.What is not includedOur fee covers the drawings only. Significant site-driven work is separate and project-specific — for example a new sewer lateral, concrete slab cutting in a garage conversion, water-service upgrades, and especially utility water and sewer connection fees, which some California districts charge in the thousands to over fifteen thousand dollars. City permit fees are also separate.Plumbing bundled vs. standaloneMost new-construction ADUs are best served by the Full MEP Package, where plumbing is included from $1,495 — far less than buying three separate single-discipline sets. A standalone plumbing order ($995 and up) is the right call when another discipline is handled elsewhere, such as an attached ADU that reuses the main house electrical and HVAC but still needs new water and DWV piping. Whichever route you choose, the plan fee is the same statewide with no sales tax.Every plumbing order includes two revisions, city corrections, and permit-ready PDF delivery. See the pricing page or start an order.

Question 7

How much does Title 24 cost?

Accepted Answer

A Title 24 energy compliance report is a flat +$240 add-on when ordered with any of our MEP plans — the same price regardless of ADU square footage. Bundling it with your plans is both cheaper and more accurate than sourcing it separately.Title 24 pricing at a glanceItemPriceTitle 24 energy report (CF1R) add-on+$240Price variation by square footageNone — flat feeSingle discipline + Title 24 (up to 600 SF)$995 + $240 = $1,235Full MEP + Title 24 (up to 600 SF)$1,495 + $240 = $1,735Full MEP + Title 24 (1,001–1,200 SF)$2,595 + $240 = $2,835What the Title 24 report isWhen people say "Title 24," they mean the energy compliance documentation required under Part 6 of the California Building Standards Code. For an ADU this is typically the CF1R Certificate of Compliance, which establishes the minimum efficiency requirements your project must meet — HVAC efficiency, water heater efficiency, lighting power density, insulation, and window performance.Why bundle it with your MEP plansCoordination: the equipment listed on your mechanical and plumbing plans must match the efficiency values in the energy model. When one team prepares both, they agree from the start, eliminating a leading cause of plan-check corrections.Single submittal: the report and plans arrive together, ready for the building department.Flat, transparent price: $240 whether your ADU is 500 SF or 1,200 SF.What $240 does and does not includeThe $240 covers preparation of the energy compliance report itself. It does not include HERS field verification testing, which is a separate service performed on site by an independent, certified HERS rater after construction (for items such as duct leakage, refrigerant charge, or fan watt draw, where the design requires them). HERS testing is contracted and billed directly by the rater, not by us. City permit and plan-check fees are also separate.Under the 2025 California Energy Code, in effect for permit applications submitted on or after January 1, 2026, all-electric heat-pump designs are the most straightforward path to compliance — so getting the report right the first time matters.Add Title 24 to your plans at checkout. See Title 24 reports, the pricing page, or start your order.

Question 8

What additional fees should I expect?

Accepted Answer

Our plan price is flat and all-inclusive for the engineering work itself — single disciplines from $995, two from $1,195, and the Full MEP Package from $1,495, all including two revisions, city corrections, and permit-ready PDF delivery with no sales tax. However, building an ADU involves several third-party fees that are not part of our scope, and it is important to budget for them so nothing comes as a surprise.What IS included in our priceIncluded at no extra chargeTwo rounds of revisionsCity plan-check corrections until permit issuancePermit-ready PDF deliveryNo sales tax on plan servicesStandard 5-business-day turnaroundOptional charges from usOptional add-onPriceTitle 24 energy report+$240Priority turnaround (3 business days)+$299Expedited (1–2 business days)+$599Third-party fees that are NOT part of our scopeCity permit and plan-check fees — charged by your local building department to review and issue the permit. These vary widely by jurisdiction.School and impact/development fees — some agencies assess these on new living area, though many ADUs under 750 SF are exempt under state law.Utility connection fees — water, sewer, gas, and electric service connections billed by your utility or district. Water and sewer connections in particular can range from modest to many thousands of dollars depending on the agency.Structural and architectural drawings — the floor plans, elevations, and structural engineering that accompany an MEP set. We prepare MEP only.HERS field verification testing — on-site testing by an independent certified HERS rater after construction, where the energy design requires it. Billed by the rater.Site-specific construction work — new sewer laterals, slab cutting in garage conversions, panel/service upgrades, and similar items are contractor scope, not plan 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.Because these outside fees depend entirely on your city, lot, and utility, confirm them early in planning. For a full picture of the process, read how it works and the complete ADU MEP guide, or review our FAQ. When you are ready, see the pricing page or place your order.

Cost of ADU MEP Plans

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