ADUs & Garage Conversions in San Francisco, Designed Around How You Live
An ADU is the most rule-bound build in San Francisco — state ADU law, the city's local program, fire separation, and a lot that's usually already full all shape what you can put where. Done right, a backyard cottage or garage conversion adds real space and real value. We design to what's actually permittable and build it under one roof, from feasibility through SF permitting to final inspection.
We build detached ADUs, garage and ground-floor conversions, and junior ADUs across San Francisco — permitted through SF Planning and SF DBI under California’s ADU law and the city’s local program. One team handles design, permitting, and construction on a single contract, so the unit that gets approved is the one that gets built.
Who This Service Is For
Homeowners Planning to Stay Long-Term
You want the flexibility an ADU gives — a place for a parent or adult kid now, rental income later. You want it built legally, to code, and to a standard that doesn’t feel like a tacked-on shed.
Growing Families
You’ve got an underused garage, basement, or backyard, and you want to turn it into real, permitted living space — adding square footage and value without leaving the lot you love.
Real Estate Investors
You’re adding a legal unit to improve the property’s income and value. You want clean permitting under the ADU rules and a builder who delivers a rentable unit on schedule.
SIGNATURE MOMENTS
What separates a WDC ADU from a garage conversion.
Zoning expertise built in
We know SF and SF ADU rules — setbacks, FAR limits, owner-occupancy requirements — and design around them from day one.
Fully permitted from day one
Every WDC ADU is designed and built to code with full permits. No shortcuts that create liability when you sell or rent.
Independent living standards
Separate entrance, dedicated HVAC, full kitchen and bath — designed to function as a genuinely livable, rentable unit.
ENGAGEMENT MODEL
Three phases. One permitted ADU. Zero surprises.
Flat-fee at every phase. You know your investment before a permit is pulled.
PHASE 01
Discovery
We evaluate your lot, zoning envelope, setbacks, and utility capacity — then scope a unit designed to maximize what your property allows.
PHASE 02
Design
Floor plan, structural drawings, MEP coordination, and finish selections — all resolved before we approach the building department.
PHASE 03
Construction
Foundation, framing, rough trades, insulation, and finish — one team executing from slab to final inspection.
What You Can Build
Detached cottages, garage and ground-floor conversions, and junior ADUs each follow different rules. We start by reading your lot against state and SF ADU law, so the design targets what’s approvable, not just what’s wished for.
Layout in a Small Footprint
An ADU lives or dies on the plan — making 400 to 1,200 square feet feel like a real home, with full-height storage, a workable kitchen, and light brought in wherever the lot allows.
Code, Fire & Utilities
Fire separation, egress, a separate or sub-metered utility connection, and Title 24 compliance are where ADUs get complicated. We engineer them in from the start so the unit passes inspection the first time.
Finishes Built to Rent or Live In
Durable, honest finishes that hold up to a tenant and still feel like home — efficient systems, real storage, and materials chosen to last, not to cut a corner.
The Old Way
- Separate designer and contractor
- Unclear budgets and change orders
- Delays caused by poor coordination
- Limited accountability when problems arise
Our Design-Build Approach
- One integrated team from concept to completion
- Clear scope, transparent pricing, and realistic timelines
- Fewer delays and better communication
- Full responsibility for design, permits, and construction
Why Remodeling Your ADU Is Worth It
Increase Property Value
A permitted ADU adds both square footage and an income stream — one of the strongest value moves available on an SF lot, as long as it’s legal and built to last.
Improve Daily Functionality
Flexible space for family now and rental income later, without leaving the home and lot you already own.
Modernize the Look and Feel
A small building done with real care — efficient, durable, and designed to feel like a home, not an afterthought in the backyard.
PROCESS AT A GLANCE
One team. One timeline.
From site assessment to final city sign-off, one firm owns the outcome.
STAGE 01
Discovery
2–4 weeks
Zoning review, site assessment, utility capacity check.
STAGE 02
Design
6–10 weeks
Floor plan, structural drawings, MEP coordination, finish selections.
STAGE 03
Permit
8–20 weeks
City submission, plan check, corrections, approval.
STAGE 04
Build
4–9 months
Foundation through final inspection and certificate of occupancy.
What to Expect During a ADU Remodel
An ADU in San Francisco is permitted through SF Planning and SF DBI under state and local ADU rules. The state has streamlined ADU approvals, but site conditions, fire separation, and utilities still drive the timeline. Expect a design and permitting window, then construction. We map the real schedule in feasibility.
What Impacts the Cost of an ADU Remodel
- One integrated team from concept to completion
- Clear scope, transparent pricing, and realistic timelines
- Fewer delays and better communication
- Full responsibility for design, permits, and construction
- One integrated team from concept to completion
- Clear scope, transparent pricing, and realistic timelines
- Fewer delays and better communication
- Full responsibility for design, permits, and construction
Professionals Tips
Increase Property Value
A permitted ADU adds both square footage and an income stream — one of the strongest value moves available on an SF lot, as long as it’s legal and built to last.
Improve Daily Functionality
Flexible space for family now and rental income later, without leaving the home and lot you already own.
Modernize the Look and Feel
A small building done with real care — efficient, durable, and designed to feel like a home, not an afterthought in the backyard.
Increase Property Value
A permitted ADU adds both square footage and an income stream — one of the strongest value moves available on an SF lot, as long as it’s legal and built to last.
Improve Daily Functionality
Flexible space for family now and rental income later, without leaving the home and lot you already own.
Modernize the Look and Feel
A small building done with real care — efficient, durable, and designed to feel like a home, not an afterthought in the backyard.
What Our Clients Say
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We Do Construction, Inc.
Featured ADU Construction Projects
Recent San Francisco ADUs — detached backyard cottages, garage conversions, and junior ADUs across the city’s tight lots.
ADU & Garage Conversions by City
Serving San Francisco and Surrounding Areas
- ADU & Garage Conversions in Berkeley
- ADU & Garage Conversions in Concord
- ADU & Garage Conversions in Daly City
- ADU & Garage Conversions in Marin
- ADU & Garage Conversions in Mill Valley
- ADU & Garage Conversions in Millbrae
- ADU & Garage Conversions in Noe Valley
- ADU & Garage Conversions in Oakland
- ADU & Garage Conversions in Orinda
- ADU & Garage Conversions in Pacific Heights
- ADU & Garage Conversions in Pacifica
- ADU & Garage Conversions in Pleasant Hill
- ADU & Garage Conversions in San Francisco
- ADU & Garage Conversions in San Rafael
- ADU & Garage Conversions in Vacaville
- ADU & Garage Conversions in Walnut Creek
FAQ
Yes — we permit ADUs through SF Planning and SF DBI under California’s ADU law and the city’s local program, and carry the job through every inspection. The state has streamlined approvals, but the set still has to be right.
Detached backyard cottages, garage and ground-floor conversions, and junior ADUs (a bedroom-plus-kitchenette within the existing home). Which one fits depends on your lot, your home, and the rules — we read all three first.
It depends on your lot and the applicable ADU rules — generally up to around 1,200 square feet for a detached unit, with conversions sized to the existing space. We confirm the real number for your property in feasibility.
Plan on a design and permitting window followed by construction — often several months to about a year door to door, depending on whether it’s a conversion or a ground-up cottage. We give you the real schedule up front.
It depends heavily on type — a garage conversion and a detached ground-up cottage are very different numbers, and utilities and site access move the figure. We price it out of a real feasibility study, not a per-foot guess.
Yes — a permitted ADU is a legal rental unit, which is much of the point. We build to a standard that rents well and holds up, and make sure the utilities and separation are done by the book.
Yes — design, permitting, and construction sit under one contract. With ADUs especially, designing to what the rules actually allow before building is what keeps the project from stalling.
We start with a feasibility study of your lot and the ADU rules that apply, then put a fixed proposal in writing — what design, permits, utilities, construction, and contingency cover — before any work begins.
How much does a garage conversion ADU cost in San Francisco?
In San Francisco, converting an existing garage into a legal ADU typically costs $120,000 to $250,000 as of 2026 — roughly $300 to $600 per square foot, rising to $500–$667/sq ft for luxury finishes. That budget covers a permitted unit with a bathroom, kitchenette, insulation, heating, and upgraded electrical. Permit and plan-review fees alone generally run $3,000–$15,000 depending on scope. We Do Construction (CSLB #1096552) builds garage-conversion ADUs across San Francisco and the Bay Area on a fixed design-build contract.
| Tier | Typical range (2026) | What's included |
|---|---|---|
| Essential conversion | $120,000–$160,000 | Studio layout, standard finishes, existing slab |
| Signature conversion | $160,000–$210,000 | 1-bed layout, custom millwork, new plumbing runs |
| Estate conversion | $210,000–$250,000+ | Architect-grade finishes, structural/foundation work |
Cost data: Barcci Builders Bay Area guide, 2026; GatherADU 2026 cost guide; Angi garage-to-ADU data, 2026. Last updated June 2026.
How long does an ADU permit take in San Francisco?
California law requires cities to approve complete ADU applications ministerially within 60 days (Gov. Code §66314), and since January 1, 2026, SB 543 gives San Francisco just 15 business days to deem an application complete or issue a written correction list. In practice, design-through-permit in San Francisco still runs 5–10 months once revision cycles are counted, with full project timelines of 7–9 months common for garage conversions. San Francisco has also offered pre-approved ADU plan sets since January 2025, which can compress design and review substantially. We Do Construction manages the entire SF Planning and DBI process in-house.