Turn your Backyard into
Extra Space and Income

It’s never been easier to build an ADU (Accessory Dwelling Unit)

How it Works

1. Free Consultation

Onsite Visit

2. Design 2-6 Weeks

Design Your Custom ADU

3. Permitting 4-8 Weeks

Relax as we handle Permitting

4. Construction 12-16 Weeks

Build with Local Trusted Professionals

Why Work With Us?

Hassle-Free Process

We  handle your project from design to permitting to construction. Our Team of Experts will help you maximize return and minimize stress.

Guaranteed Pricing

Our innovative & building process allows us to build your ADU at a guaranteed fixed Price with Zero hidden fees. No Surprises, No Price changing.

Trustworthy Team

Our local contractors are Licensed, Bonded, and Insured. Each builder is fully qualified, vetted, and prepared to deliver your ADU.


Yes! New California state regulations mean nearly all residential properties (both single family and multifamily) are eligible for ADUs. Additionally, municipalities must allow all ADUs of up to 800 sq. ft. in size with 4 ft. property line setbacks and up to 16 ft. in height under the new California Statewide Exemption ADU rules. Most municipalities allow larger ADUs with even fewer restrictions, and these vary from city to city.

Accessory Dwelling Units can come in many shapes and sizes, from an attached garage conversion or an in-law suite to a backyard guest house or a basement studio apartment. The best ADU design is one that matches the use cases, budget, and needs of both you and your property. ADUMAXX’s architectural design team can help bring the best ADU for you to life.

ADUMAXX’s in-house design team specializes in only ADUs, creating efficient and elegant small space designs that result in a smoother permitting process. After the initial permit submission to the local municipality, our permit operations team works hand-in-hand with our design team to address plan check comments promptly while keeping you in the loop. Cottage has built local permitting expertise in over 50 municipalities – we’ve likely permitted an ADU in your city already!

ADUMAXX’s ADU builder partners are local construction experts that specialize in ADUs and have decades of experience building in your area. ADUMAXX carefully vets all potential contractors to ensure that they not only do high-quality work, but also deliver projects at great, consistent prices.

Free No Obligation Consultation!

We’re Here To Help
7 AM – 7 PM · Mon – Sat