How much do MEP plans cost for an ADU in California?

Traditional California engineering firms typically charge $2,500 to $6,500 for a complete residential ADU MEP set. Our pricing is well below that. We use flat pricing scaled by ADU square footage, so you know the cost up front with no hourly surprises and no sales tax.

Our pricing at a glance

What's included in every order

• Two revisions at no extra charge
• City plan check corrections handled until permit issuance, at no extra charge
• Permit-ready PDFs formatted for 24" x 36" submittal
• Standard 5 business day turnaround included; no sales tax

Optional upgrades

• Priority turnaround — 3 business days, +$299
• Expedited — 1–2 business days, +$599
• Title 24 report — bundled for +$240, which keeps your energy model and mechanical sheets aligned and reduces corrections

What actually moves the price

Two factors drive your final number:

1. Square footage — flat pricing scales with the size of the ADU, so a compact studio costs less than a large two-bedroom unit.
2. How many disciplines you need — a single-discipline electrical-only set is far less than a full M/E/P package.

What does not happen is open-ended hourly billing. Because pricing is flat and scoped up front, the quote you see is the price you pay, including the revisions and corrections that traditional firms often bill separately.

A sample budget for a typical ADU

To make the numbers concrete, here is how a common scenario might come together. Final pricing scales with square footage, so treat this as illustrative rather than a quote:

The same scope from a traditional firm — engineering, the energy report, and the revision rounds — frequently lands in the $2,500–$6,500 range once hourly fees and per-revision charges are added up, which is why the flat-rate approach tends to come out well ahead.

Why "included" matters as much as the headline price

When comparing quotes, look past the starting number to what is bundled. Two providers can advertise similar base prices, yet one bills separately for load calculations, revisions, and correction responses while the other includes them. Our pricing folds in two revisions and city corrections until permit issuance at no extra charge, so the figure you see is far closer to your true all-in cost.

How to think about value

Bundling all three disciplines in the Full MEP Package (from $1,495) costs less than buying them separately, and adding Title 24 from the same team avoids the coordination errors — and resulting plan-check corrections — that happen when the energy report and the MEP plans come from different sources.

For the complete tier-by-tier breakdown, see the pricing page, and for context on what drives the numbers, the Cost of MEP Plans USA guide. When you're ready, you can configure your exact package on the order page. Pricing is California-only.