Renowned Custom ADU Builders in Portland, OR

The cost of a freestanding ADU in Oregon can vary widely based on size, design, site conditions, and finishes. Our builders work with you early in the planning process to align your goals with a realistic budget.

Whether your project is part of a larger outdoor living transformation or a stand-alone undertaking, we ensure everything is thoughtfully integrated into your property. This helps avoid unexpected costs by keeping everything transparent and coordinated from the start.

You will never be left guessing where your money is going. You get a complete, high-quality build with no surprises and a final result that reflects your vision, just like we’ve done for many home remodeling clients in Beaverton and other nearby areas.

There are state-wide ADU regulations in Oregon, and local jurisdictions like Portland or Lake Oswego often add their own requirements around size, height, parking, and more. Every contractor in Portland needs to keep up with every change in the code. We stay up-to-date with these changes and manage all zoning and permitting for you.

We’ll evaluate your property to ensure your project meets both state and local rules, and advise you on what’s possible before we begin designing it. You won’t need to navigate the red tape because we do it for you.

In Portland, the placement of a detached accessory dwelling unit relative to your primary residence and property lines is governed by specific zoning regulations. While there isn’t a mandated minimum distance between the new construction and the main house, it needs to adhere to the setback requirements of your property’s base zoning district. These setbacks typically include:

• Side and rear setbacks: Generally, a minimum of 5 feet from the side and rear property lines.
• Front setback: The unit must be located at least 40 feet from the front lot line or behind the rear wall of the primary dwelling.

It’s important to note that these requirements can vary based on the specific zoning of your property and any applicable overlay zones. However, this is nothing to worry about since your ADU contractors will handle all aspects of zoning analysis and site planning for you, just like for any home remodeling project.

Typical custom ADU construction in Portland usually takes 6 to 12 months, depending on factors like design complexity, size, and local permitting processes. The timeline may also be affected by weather conditions, site preparation, and utility installations. 

Keep in mind that unexpected delays, such as supply chain issues or zoning complications, could extend the project timeline. Working with our experienced custom ADU builders can help ensure a smoother, more efficient process, while managing expectations for any potential delays.

Your ADU contractor will likely explain that in most Oregon cities, a detached accessory dwelling unit can be up to 800 square feet, though some areas allow more depending on your lot size and local code. The city recently lifted certain restrictions, which can open up larger build options if your site qualifies.

Your dedicated builder will take these variables into account when designing your space and will walk you through what’s allowed on your property. Our goal is to get you the most usable space possible while staying compliant. You’ll get a custom addition that maximizes both square footage and long-term value.

Definitely! In fact, partnering with reputable custom ADU construction services is an excellent way to generate rental income. Many homeowners build ADUs specifically for renting out to tenants, providing a private living space with its own entrance and amenities. This additional space can be rented on a long-term basis or even as a short-term rental, depending on local laws. 

High-quality ADU construction can create a steady stream of rental income that can potentially cover your mortgage costs, put more money in your pocket, and increase your property’s overall value.

COOPER Design Build is Portland’s trusted ADU construction company, providing quality, custom home renovations, which include beautifully constructed freestanding ADUs. With decades of experience and a fully integrated team of designers and builders, we handle everything from design and permitting to construction and finishing details. 

We take on a wide range of projects, including thoughtfully planned condominium renovations, and serve clients throughout the region, from Portland to high-end home remodeling in Lake Oswego, and much more. Whether you’re tucked near Forest Park or overlooking the Willamette River, we bring thoughtful design and lasting value to every square foot. 

Schedule your consultation today with our award-winning experts in ADU construction and take the first step toward building something exceptional!