One licensed team designs and engineers your complete ADU plan set, drawn for San Diego Development Services approval. Flat price up front, free corrections until your permit is issued. Permit-ready in 2–4 weeks.
Free feasibility check included. No obligation, no hourly billing.
Every ADU plan set includes architectural drawings, structural engineering, and Title 24 energy calculations, everything San Diego Development Services needs to issue your permit, from one team.
New backyard homes up to 1,200 sq ft, a full architectural, structural, Title 24, and MEP set drawn for San Diego review. The mechanical, electrical, and plumbing sheets come from our own MEP design team in San Diego.
From $4,850
The fastest, most affordable ADU in San Diego. Plans, structural check, and energy compliance for converting your existing garage.
From $2,850
Junior ADUs up to 500 sq ft carved out of your existing home, an efficient way to add a rental unit within your walls.
From $2,650
ADUs attached to the main house, over-garage units, and room additions with full structural design.
From $3,650
Lots in Transit Priority Areas may qualify for extra units under the San Diego ADU Bonus Program. We check first, then design.
Flat-fee proposal
ADU builders and general contractors: we produce plan sets under your brand for your clients, at volume.
Custom quote
San Diego layers its own regulations on top of state ADU law: the ADU Bonus Program in Transit Priority Areas, coastal overlay zones that trigger Coastal Commission review, and Development Services formatting standards. We draw every set to the current City of San Diego rules, so plans clear plan check with fewer correction cycles.
Where you submit matters too. Parcels inside the City of San Diego go through Development Services and its dedicated ADU review track, while Chula Vista, Oceanside, Carlsbad, Escondido, El Cajon, and La Mesa each run their own building departments with their own checklists, and unincorporated lots go to the County of San Diego instead. We tell you which desk your project lands on, and what that means for timeline, before you sign anything.
Address, photos, and what you want to build, we check zoning and feasibility free.
One flat price for the complete permit set. No hourly surprises.
Architecture, structural, Title 24, and MEP produced as one coordinated set.
Submit to San Diego DSD. We answer plan-check corrections free until approval.
Architecture, structural engineering, MEP, and Title 24 together, no juggling three firms whose drawings don’t match.
A flat written proposal before any work starts, never hourly billing.
Most ADU plan sets delivered in 2–4 weeks; corrections answered free.
White-label plan production for ADU builders and GCs who need overflow capacity.
Service areas: San Diego, La Jolla, Pacific Beach, North Park, Chula Vista, Encinitas, Carlsbad, El Cajon, La Mesa, Clairemont, and all of San Diego County. See also our ADU & JADU design service and structural engineering in San Diego.
An ADU permit set is not one drawing, it is the full stack of sheets a Development Services plan checker walks through line by line. Here is what we deliver, and why each piece exists in San Diego specifically.
Floor plans, elevations, sections, and a zoning-checked site plan showing setbacks, lot coverage, and the existing home, formatted to Development Services standards for the city’s dedicated ADU review track. Formatting sounds trivial until a set bounces for a missing sheet reference, so we treat it as part of the design.
San Diego’s bonus program lets qualifying lots, mainly in Transit Priority Areas, add a bonus ADU for each deed-restricted affordable unit, which can turn a backyard project into a small multi-unit building. We check whether your lot qualifies, then lay out unit count, access, and open space so the bonus actually pencils.
Projects west of Interstate 5 often sit in the coastal overlay zone, where an ADU can need a coastal development permit or an exemption finding. La Jolla, Pacific Beach, Ocean Beach, and Point Loma trigger this routinely, and salt air adds hardware corrosion requirements. We flag coastal conditions at quoting, not at plan check.
Nearly all of San Diego County falls in a high seismic design category, and the Rose Canyon fault runs directly under the city. Two-story ADUs and units over garages need genuine gravity and lateral design, and we run the analysis for your actual site values, not defaults a plan checker will question.
Inland San Diego sits on expansive clay in many areas, parts of Mission Valley carry liquefaction mapping, and canyon-edge lots in neighborhoods like Talmadge and Mt. Helix add steep-slope rules. All of it changes the foundation and the site plan, so we price the real conditions before you commit.
Energy calculations run for San Diego’s actual climate zone, plus electrical, plumbing, and mechanical sheets that match the architectural set because one team produces all of it. And every proposal includes answering Development Services correction comments free until your permit is issued.
The most common way a San Diego ADU submittal stalls is an overlay found late: a design worked up for a standard lot that turns out to sit in the coastal zone, or on a canyon edge, and has to be reworked after the first correction letter. The second is a multi-unit bonus project drawn like a single backyard cottage, without the structural and access design a small apartment building actually needs. Both problems are avoidable if the designer prices the real conditions up front, which is exactly what our free feasibility check does before you commit to anything.
A complete permit-ready ADU plan set from Fast Build runs $2,650 to $9,650 depending on size and complexity. A JADU or garage conversion sits at the low end; a large new detached ADU with full structural, Title 24, and MEP sits at the top. You get one flat quote up front, never hourly billing.
We deliver most complete ADU plan sets in 2 to 4 weeks. San Diego runs a dedicated ADU review track, and state law requires the city to approve or deny a complete application within 60 days. We answer Development Services plan-check corrections at no extra charge so the clock keeps moving.
It is a City of San Diego incentive that lets qualifying lots, mainly in Transit Priority Areas, build an extra bonus ADU for each deed-restricted affordable unit. It can allow more units than the statewide baseline. We check whether your lot qualifies before you commit to a design.
Yes. Garage conversions are the most cost-effective ADU in San Diego because the structure already exists. State law waives setback requirements for converting an existing structure and requires no replacement parking. We produce the architectural plans, the structural check, and the Title 24 energy calculations as one set.
No, that is the point of Fast Build. Architectural design, structural engineering, Title 24 energy compliance, and MEP come from one licensed team in one coordinated permit set, so you never shuttle drawings between three different firms.
Yes, in most cases. Parcels west of Interstate 5 often sit in the coastal overlay zone, where an ADU can require a coastal development permit or an exemption finding on top of the building permit. La Jolla, Pacific Beach, Ocean Beach, and Point Loma trigger this routinely. We check your parcel’s overlay status in the free feasibility check and design to it from day one.
Often yes. Height limits rise near transit and under the city’s ADU rules many lots can carry a two-story unit or an ADU over a garage. A second story turns the project into a real structure with gravity and lateral design requirements, which is why our sets include full structural engineering rather than leaving it to a separate firm.
Yes. Chula Vista, Oceanside, Carlsbad, Escondido, El Cajon, La Mesa, Santee, Vista, and unincorporated San Diego County each run their own building departments with their own checklists, and we format the set for whichever jurisdiction your parcel is in.
Free feasibility check on your lot + a flat-price quote within 24 hours. No obligation.
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