ADU Construction

More Space, Built the Right Way

Adding an ADU (Accessory Dwelling Unit) is one of the smartest ways to get more from your property. At Century Home Builders, we handle everything—from permits and planning to final inspection. Whether it’s for family, rental income, or extra space, we make sure your ADU is built to last.

We’ve worked across Marin, San Francisco, and the Bay Area, navigating strict codes and small lots. Our team handles the full process so you don’t have to worry about delays or red tape.

We Handle It All

Detached, attached, garage conversion—we make it simple.

We help you design and build an ADU that works for your property and your life. Whether you need rental income, a guest suite, or more space for family, we handle everything from city approvals to final inspection.

You don’t have to manage plans, permits, or contractors—we do it all. And we keep you updated every step of the way.

What We Do

Site evaluation and planning
Architectural design and layouts
Foundation, framing, and roofing
Electrical, plumbing, and HVAC
Kitchens, bathrooms, and finishes
Permits, inspections, and approvals

How the ADU Process Works

We keep the process clear and straightforward:

Initial Consultation – We assess your lot and talk through goals.
Design & Permits – We create a layout and submit plans to the city.
Construction – Our team builds the unit from the ground up.
Final Inspection – We finish with a walkthrough and city approval.

We’ve helped homeowners across the Bay Area navigate tough codes and small spaces. We know how to get it done.

Serving the Bay Area

We build ADUs in Marin, San Francisco, San Mateo, and surrounding areas. We’re familiar with local rules, zoning, and setback requirements—and we’re quick to catch things that could cause delays.

Testimonials

Julie S. 4 weeks ago

Mark responded within 5 minutes of my search on yelp, and was very easy to schedule an appointment for our slow bathroom drains. Very communicative, on-time day of service, and professional. Took care of the sink and bathtub drains quickly and neatly. Best priced on the 4 other quotes received as well. He even followed up a month later to make sure everything was still working well. Excellent experience all around.

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Luke T. 1 month ago

My house has old water pipes leaking problems. It's better replaced it to the copper pipe. The team are very professional fixed and replacement main water pipes very quickly. Gregory has very good professional skills to do all the jobs and make sure all connections has been sealed with no any leaking issues. Gregory work very hard and friendly. We are very happy has worry free new water line in my house and it will last for longtime. Great team and value do the good work. Thanks

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Ken C. 1 month ago

Mark came on a Sunday to help us fix our water thumping noise issue. He's an expert at diagnosing problems. He narrowed down to the kitchen faucet that had a flexible hose inside that expanded and contracted when we turned on off the valve. He offered a range of options and tried the least expensive option to see if it addressed our issue. He didn't push did the most expensive option. We appreciate mark's professionalism. We are very happy and would recommend him to our friends.

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Art L. 1 month ago

I hired Century Home Services to look into a leaky garbage disposal issue in our kitchen. Mark was great to talk to, clearly explained what the issue could've been, and gave me a reasonable quote. There was a smidgen of a phone tag issue, which was entirely Yelp's fault, as some of Mark's messages were forwarded to my phone and others were not. Mark rescued the situation by being very quick to answer the phone (unlike many other contractors!) and flexible with his scheduling.

Even with that little hiccup, Mark and Gregory showed up the next day and fixed the garbage disposal quickly and professionally, with no mess and no fuss.

This was a relatively small issue that could've become a big problem, and I'm glad I hired Century when I did. If we have a plumbing project again, I'll be calling Mark, and you should too.

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