ADU Contractor in Chico, Modesto, San Luis Obispo & San Diego, CA
ADUs in California
S&K Construction handles accessory building units, or ADUs, in Chico, Modesto, SLO, San Diego, and surrounding areas. We take a collaborative approach to help you shape your vision for a tiny home, whether it’s for expanded space, guests, or long-term rental. As a licensed, insured, and experienced ADU contractor, we’ll guide the process, handling planning, permitting, and building — and our relationship doesn’t end after you move in. With 45+ years of experience, S&K is a contractor you can trust.
Learn more about building an ADU in California.
Lorem ipsum dolor sit amet. Ad deleniti obcaecati aut porro commodi qui aliquam aperiam ut voluptas porro ex suscipit ducimus. Rem nisi impedit ut minus laboriosam hic sunt odit aut dolor omnis quo perferendis deleniti ab mollitia quis.
Lorem Name
title / position
What We Do
Our Services
Custom Homes
Build your dream home from the ground up. We work with homeowners who want to be involved in the design, taking your vision and making it reality.
Renovations & Remodels
Whether you need a whole home renovation or just a kitchen and bath remodel, we can take existing spaces and make them feel brand new.
Insurance Rehabilitation
We specialize in working with insurance companies when you have issues at your home — from water damage to roof repair, our expertise has you covered.
Storm Damage Repair
When the unthinkable happens, we are here to help restore your property and home back into livable condition.
See Our Results
Our Work
Our Values
Why S&K
01
Flexibility
Whether you have blueprints in hand or need help from the ground up, we adapt to the situation — offering the support you need, tailored to your goals.
02
Proven Track Record
With over 4 decades of success, you can trust that we have the experience to get jobs done efficiently, with high-quality results.
03
Integrity
No surprises — just clear communication. We provide upfront pricing, detailed scope, and transparency throughout our process.
04
Expertise
Our deep knowledge makes us an expert resource in challenging situations, whether it's a new build or insurance claims and reconstruction work.
05
Community Focus
We like to give back by being involved in local non-profits like Crossroads Church, Ducks Unlimited, and the Quarterback Club
Planning for Your ADU Build in California
Building an Accessory Dwelling Unit (ADU) in California has become significantly more streamlined due to recent 2024–2026 state legislative updates and local initiatives designed to address the housing shortage. The city currently offers an ADU Express Program that provides a same-day, coordinated plan review for qualifying projects to accelerate the permitting process. Standards include:
- Size & Type: You can build detached ADUs up to 1,200 square feet or Junior ADUs up to 500 square feet.
- Setbacks: State-mandated setbacks are generally 4 feet from the side and rear property lines, regardless of local zoning.
- Pre-Approved Plans: The city and Stanislaus County provide free, pre-approved architectural plans to reduce design costs and speed up approval.
- Fees: Impact fees are typically waived for units under 750 square feet, and new 2026 laws further limit school impact fees for smaller units.
- Financing: Modesto homeowners may have access to a local $50,000 revolving loan fund through the VFCU to assist with construction costs.
Need Answers?
California ADU FAQs
Do you coordinate with architects and designers?
Yes we do! We can work with existing architectural plans, or guide you through a design-build process from scratch. Our process is designed to be collaborative and customized to suit your needs.
How involved can homeowners be in the ADU build process?
We love to work with homeowners who want to be part of the construction process, but we are equally capable of working with clients who prefer a hands-off approach. We personalize our service with clear communication, attention to detail, and a tailored process, all to deliver quality results.
How expensive is an ADU build in central CA?
Building an ADU in central California typically costs between $150,000 and $350,000, with price points largely determined by the construction type and square footage. New detached units generally range from $200,000 to over $400,000 due to the need for new foundations and utility trenching. Costs can be mitigated by staying under 750 square feet to avoid city impact fees or by utilizing the city’s free pre-approved architectural plans. While soft costs like permits and school fees usually add $6,000 to $10,000 to the total, Modesto’s specific financing programs and streamlined permitting help keep the overall investment more manageable than in other parts of California.
What's the difference between a tiny home and an ADU?
Tiny homes and ADUs are used as an interchangeable term. However, the term ADU specifically refers to a secondary structure, meaning the lot also has a primary residence. A tiny home can be a standalone structure on a lot.
What are the benefits of adding an ADU in central California?
ADUs have many benefits. ADUs are a great way to expand the livable space in your home, create privacy for guests, or add space for loved ones to age in place. In addition, ADUs can serve as long-term rentals in Modesto, adding the opportunity for rental income.
Do Chico, SLO, and San Francisco offer pre-approved ADU plans?
Yes, Chico and Modesto offer free, pre-approved ADU plan catalogs; SLO County offers pre-reviewed ADU plans; and San Francisco offers ADU pre-approval but not a free, citywide plan set.
Modesto: Offers free, pre-approved ADU plans (260 sq ft studio to 1,192 sq ft three-bedroom, including a two-story above-garage option). Using these plans qualifies you for the ADU Express Program with same-day plan review. You still submit a site-specific plot plan and pay standard permit fees.
Chico: Offers free, pre-approved ADU plans downloadable from the city website. The city provides 14 different pre-approved designs. This is the closest match to Modesto’s model.
SLO County (San Luis Obispo): Offers a Pre-Reviewed ADU Program with county-reviewed plans for eligible single-family properties. This is similar to pre-approved plans but is not described as a free city-provided plan catalog like Modesto or Chico.
San Francisco: Has an ADU pre-approval pathway, but there is no free, citywide catalog of pre-approved ADU plans like Modesto’s or Chico’s. You submit a site-specific application and must comply with the city’s zoning and permit requirements.
Bottom line: If you want free, ready-to-download pre-approved ADU plans like Modesto, Chico is the best match. SLO County offers pre-reviewed plans as an alternative. San Francisco pre-approves ADUs but does not provide a free plan library.