Davis Free Pre-Approved ADU Plans: Your 2026 Build Guide

Davis sits in an unusual position among California cities. UC Davis enrollment creates near-permanent housing pressure — vacancy rates regularly hover near zero. The city government has responded by actively encouraging ADU construction.

California's AB 1332, signed in 2023, requires cities to establish pre-approved ADU plan programs. Davis was already ahead of this deadline. The city developed its own catalog of pre-reviewed plan sets that homeowners can download and use at no cost — a genuine policy attempt to reduce the friction that stops many homeowners from building.

Want a ballpark on your specific Davis lot before going further? Run a free AI estimate at SafewayQuickQuote.com — takes about two minutes with no contractor visit.

The Three Plan Sizes: What You're Choosing Between

Davis's pre-approved catalog covers three tiers. Confirm the current plan catalog and exact square footage with the City of Davis Building Division, as details can be updated — but the general tiers are:

Studio Tier (~300 SF)

A compact, efficient studio. Works well on smaller lots or in situations where the primary goal is a rental income unit for a single occupant. Near campus or in Central Davis and East Davis, studios are highly rentable — UC Davis undergraduates and graduate students regularly seek smaller units close to academic buildings.

This is the fastest build and the lowest cost. If your lot allows it and your goal is primarily rental income, the studio tier is often the financially strongest choice relative to construction cost.

One-Bedroom Tier (~565 SF)

The most popular choice for most Davis homeowners. Large enough to attract long-term tenants, including graduate students and young professionals. One-bedroom units near downtown Davis and the UC Davis campus have historically held occupancy near 100% with minimal vacancy between tenants.

This size also works for multigenerational situations — a parent or adult child who wants their own space without being fully remote from the family.

Two-Bedroom Tier (~740 SF)

The largest pre-approved option. Best suited for families, roommate situations, or maximizing rental income per unit. At roughly 740 SF, this is a complete apartment by most standards.

The two-bedroom involves more infrastructure — more plumbing fixtures, more electrical load, more finished square footage. Both build cost and complexity go up proportionally. On a large Davis lot in a neighborhood like Wildhorse, Mace Ranch, or North Davis, it's often the right choice.

What “Pre-Approved” Actually Saves

This is the part most people don't fully understand — and it matters before you decide which path to take.

What the pre-approved plans skip:

• Architectural design fees ($5,000–$15,000+ for a custom ADU design)
• Structural engineering for the building itself (already done and reviewed)
• Most of the plan check review for the building design
• Multiple correction cycles on design elements

What pre-approved plans do NOT skip:

• Site-specific engineering: you still need a stamped site plan showing your lot's foundation design, soil conditions, utility routing, and drainage
• Title 24 energy compliance documentation for your specific site
• Setback compliance verification for your specific parcel
• Building permit fees (the same regardless of which plan you use)
• Utility connection design and fees
• Site plan review by the city

In practice, this saves weeks. A custom ADU in Davis typically takes 3–4 months from design start to an issued permit. Pre-approved plans compress much of that because the design and structural review steps are already complete before you submit.

Real All-In Build Costs (2026, Davis-Area Pricing)

These are realistic ranges for a pre-approved plan ADU in Davis, including all site work, permits, utility connections, and finishes. Site conditions, utility complexity, and finish level can move costs significantly within these ranges.

Studio Tier (~300 SF): $120,000–$180,000

What drives you toward $180,000: difficult soil requiring deeper footings, an older home that needs an electrical panel upgrade, a lot where sewer or water connections require significant trenching, or premium finishes. What keeps you near $120,000: flat lot with easy access, existing 200-amp panel, standard utility connections, and mid-grade finishes.

One-Bedroom Tier (~565 SF): $160,000–$230,000

More square footage, one bathroom, a separate bedroom. The cost spread is wider because utility complexity and finish scope have more room to vary. A one-bedroom in Mace Ranch with a flat lot and good utility access could land around $165,000. The same plan on a corner lot in the older streets near downtown Davis with trickier sewer routing and a panel upgrade could reach $220,000.

The utility connection cost deserves attention. Davis properties built before the late 1980s often have 100-amp or 150-amp electrical service. Adding a dwelling unit almost always pushes the demand calculation past what an undersized service can handle. A panel upgrade and service upgrade through PG&E typically runs $3,500–$7,500, and that's before the ADU's own wiring.

Two-Bedroom Tier (~740 SF): $200,000–$300,000

The two-bedroom is essentially a small apartment — two bedrooms, full kitchen, full bath. At this size, infrastructure costs are proportionally higher.

This is where site conditions have the most leverage. A flat, well-serviced lot in Wildhorse or North Davis with an already-upgraded panel might finish near $210,000. A more constrained lot with soil work, retaining, and utility runs from the street could push past $280,000.

Rental income at this size in Davis is compelling: two-bedroom ADUs near UC Davis regularly command $2,100–$2,900/month, meaning a $240,000 investment can generate $25,000–$35,000 in gross annual rent.

Timeline: Pre-Approved vs. Custom Design

The construction timeline is the same regardless of which plan you use. The difference is entirely in the pre-construction phase. For homeowners who want rental income running as soon as possible, shaving 2–3 months off the permit phase is meaningful.

Pre-Approved vs. Custom: How to Decide

Choose the pre-approved plan if:

• Your lot is flat or has minor grade changes (less than 18–24 inches across the ADU footprint)
• Your setbacks clearly accommodate one of the three standard sizes
• Your utility connections are straightforward (water, sewer, and electrical within reasonable distance)
• You don't have strong preferences about layout beyond the standard plan
• Speed and soft-cost savings are priorities

Consider a custom design if:

• Your lot slopes more than a few feet across the footprint — the standard plan's foundation design won't apply
• You're in an older Davis neighborhood where soil or drainage conditions are non-standard
• You need a specific configuration (garage below, living space above; or an attached unit rather than detached)
• You want to match the aesthetic of a Streng Brothers house in University Estates or a particular architectural style that the standard plans don't accommodate
• You need more than 740 SF and want to maximize to the 1,200 SF state maximum

PG&E and Electrical Service in Davis

Davis is PG&E territory. This matters for ADU planning in a specific way.

Adding a second dwelling unit changes your electrical load calculations. PG&E will require a load calculation as part of the utility connection process. If your existing panel and service can't support the combined load — which is common on homes built before the 1990s — you'll need a service upgrade before the ADU can receive its own meter.

A 100-amp service upgrade to 200-amp typically costs $3,500–$5,500 depending on the work involved. If the utility line from the street also needs upgrading, that's a PG&E coordination process with its own timeline — typically several weeks for scheduling.

Budget this into your project cost upfront. We're licensed statewide in California (CA Lic. #1066117) with over 20 years building across California. Electrical coordination through PG&E for ADU projects is a routine part of what we manage as the general contractor. Call us at (530) 204-8294 if you want to talk through your specific panel situation before pulling numbers together.

The Davis Rental Market: Why This Investment Makes Sense

UC Davis enrollment runs around 40,000 students. The university is embedded in a city of roughly 70,000 people, meaning students represent a substantial fraction of the total population. Davis rental vacancy is among the lowest of any college town in California, consistently running near zero during the academic year.

Davis has strict growth boundaries that have limited residential expansion for decades. New apartment construction happens, but not at a pace that absorbs demand. For a homeowner with a lot that can accommodate an ADU, that rental dynamic means:

• Fast lease-up (units near campus typically rent within days of listing)
• Low vacancy risk
• Consistent demand across economic cycles

A one-bedroom ADU at $2,000/month generates $24,000/year in gross income. Older neighborhoods near campus — the streets between Russell Boulevard and the UC Davis arboretum, the Central Davis grid west of the freeway, and the blocks around the Davis Farmers Market — are particularly strong for rental demand because of walkability.

Permit Authority and the Application Process

Permit authority for Davis ADUs sits with the City of Davis Building Division (part of the Community Development and Sustainability Department). For the current plan catalog, permit fee schedule, and application requirements, contact the building counter at (530) 757-5610 or OnlinePermits@cityofdavis.org.

A few things worth knowing before you submit:

• Pre-application conversation. Before submitting anything, a 15-minute conversation with a city planner about your specific lot's zoning, setbacks, and lot coverage will prevent the most common delays. This is free and worth doing.
• Complete submittal from day one. California law caps ADU review at 60 days from a complete submittal. The clock doesn't start until the city accepts your application as complete. An incomplete set resets your timeline.
• Fees. Budget $7,000–$14,000 for permit and development impact fees on a typical pre-approved plan ADU. The city's planning counter can give you an estimate for your specific parcel before you commit to a plan.

For a general sense of what this project would cost, our ADU cost calculator at safewayremodel.com/adu-cost-calculator runs through the key variables in a few minutes.

Working With a Licensed Contractor on a Pre-Approved Plan Project

The pre-approved plan does the design work — it doesn't build the unit. You still need a licensed California general contractor who will pull the permits, coordinate the site engineering, manage subcontractors, and build the structure.

A few things to check before you hire:

• License number: Verify active status at cslb.ca.gov. Ours is CA Lic. #1066117.
• Scope clarity: Who handles the site plan and engineering? Who coordinates utility connections with PG&E? Who manages the permit application? A GC who leaves these undefined is leaving you with undefined costs.
• Experience with pre-approved plans: Not all contractors have submitted pre-approved plan applications in Davis. Familiarity with the building division's expectations saves time.

We have a project manager on the ground in the Davis/Sacramento region. We're a California-licensed builder with over 20 years of experience and a 5.0-star Google rating — not a company that opened a Sacramento office last month. Learn more about our Davis work at safewayremodel.com/general-contractor-davis or call directly at (530) 204-8294.

Frequently Asked Questions