Home Additions & ADUs in Hillsboro, OR | Expand Your Living Space

ADU CONSTRUCTION SERVICES IN HILLSBORO, OR TO CREATE A FUNCTIONAL SECOND UNIT

Why Home Additions & ADUs in Hillsboro, OR Are Worth the Investment

Adding on to your home in Hillsboro, OR gives you the extra space your family needs without the hassle of moving. Whether it’s a new bedroom, a larger living area, or a complete ADU designed for guests or rental income, home additions enhance both your comfort and your property’s long-term value. With the right design and expert craftsmanship, additions provide flexibility while blending seamlessly with your existing home.

Benefits of Additions & ADUs:

Hear From Our
Happy Client

What Our Clients Say

REVIEW US ON

We hired Harris & Sons to remodel part of our house and also build an addition. The project involved 3 bedrooms, 2 walk-in closets, and 2 bathrooms. Throughout the construction process, which had a few unforeseen complications, Harris & Sons worked to meet our expectations, gave us constructive options, and pushed to keep as close to the schedule as possible. They worked with us on controlling overall cost and understood and respected our financial capabilities and limits. In the end they gave us a beautiful and good quality home.

From our first meeting, Christian Harris stood out. Not only is he incredibly knowledgeable about construction and design, but he also brought a level of calm confidence that made us feel like our home was in the best possible hands. He took the time to understand our vision, walked us through every step of the process, and communicated consistently, something that’s rare in the construction world these days.

I met with Christian and a tall young man whose name escapes me, and was very impressed by their professionalism. They gave me a quote for remodeling after major water damage. Sadly I couldn't use them as I was fighting with my insurance company at the time!! I still think about the awesome job I KNOW they would've done for me and am still upset it never happened. Bobbie Pierson

We had Brian and his team Marcos & Jackson put in a privacy fence for us. The work done was outstanding and the fence looks great. I’m overjoyed by the job they did dealing with the ‘less-than-friendly” rock pile we live on. The work was done efficiently, clean, and fast. I don’t think I heard one curse-word uttered. These guys are clean, professional, quick, and darn good at what they do! I couldn’t recommend them more and we’ll be calling them again to put in our deck! Thx guys!!!

This team did such an amazing job building my pergola cover and enclosing my deck. Very professional and quality work. All of their suggestions for design were great, and I would recommend them for any project.

We have worked with Christian and his team for numerous projects around our home for the past year. They built and stained a beautiful fence for us, and also built a paver patio and pathway in our backyard. They are consistently friendly, communicative, and deliver high-quality work. Their employees are considerate and helpful. They have excellent follow-through from start to finish, and are exceptionally priced. We would highly recommend this team and we will continue to utilize their skills around our home going forward.

Everything You Need, All in One Place

What’s Included In
Our Additions & ADUs?

Room Extensions & Sunrooms

Seamless additions that match your home’s structure while offering extra light and usable space.

Garage
Conversions

Convert existing garages into stylish, functional living areas for guests, hobbies, or income potential.

Detached ADUs
(Granny Flats)

Independent living units with full amenities—perfect for rental income or multigenerational housing.

In-Law Suites

Comfortable, accessible, and private suites tailored for aging parents or guests staying long-term.

Permitting & Planning

We handle all plans, permits, and code compliance to ensure a smooth addition from start to finish.

Foundations & Framing

Built with solid foundations and framing that ensure structural integrity and long-lasting comfort.

Our 5-Step Remodeling Process

From Concept to Completion,
We Make It Easy

Initial Survey

Trusted Experience: With years of remodeling expertise, we’ve built a reputation for delivering projects that combine style, function, and long-lasting value.

Design Phase

Personalized Approach: Every home is unique. We listen carefully to your goals and create tailored solutions that bring your vision to life.

Planning & Permits

Clear Communication: From timelines to budgets, we keep everything transparent so you always know what to expect. No surprises—just results.

Construction Phase

Craftsmanship That Lasts: Our skilled professionals use premium materials and expert techniques to ensure flawless execution that stands the test of time.

Final Walkthrough & Handover

Satisfaction Guaranteed: We don’t consider the job complete until you’re 100% happy with your remodeled space—down to the very last detail.

See the Transformation

Spacious Home Additions & ADUs
We’ve Recently Completed

Expand Your Living Space with a Custom Home Addition, On Time & On Budget

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Call Us At: +1 541-316-5836

Got Questions?

Frequently Asked Questions

1. What’s the difference between an addition and an ADU?

A home addition expands your existing living space, like adding a new bedroom, bathroom, or living area. An ADU (Accessory Dwelling Unit) is a separate, self-contained unit — often with its own kitchen, bathroom, and entrance — that can be used for guests, extended family, or even rented out for additional income.

2. Do I need permits for an ADU?

Yes, building an ADU in Hillsboro, OR requires proper permits and must meet local zoning regulations. Our team at Harris & Sons handles the permitting process for you, ensuring your ADU complies with all city codes and requirements.

3. Can I use an ADU as a rental property?

Yes! ADUs are perfect for long-term rentals, guest houses, or multigenerational living.

4. How long does it take to complete a home addition?

Timelines vary, but most additions take 8–12 weeks from design to finish.

5. Will a home addition increase my property value?

Definitely. Additions add square footage and functionality, which increase resale value significantly.

Additions & ADUs Hillsboro

ADU CONSTRUCTION SERVICES IN HILLSBORO, OR TO CREATE A FUNCTIONAL SECOND UNIT

Everything You Need, All in One Place

Our 5-Step Remodeling Process

See the Transformation

Got Questions?

Where We Work

Central Oregon

Portland Metro

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