Home Additions in Portland, OR

Local Craftsmanship Since 1993, Expand Your Living Space
If your home no longer suits you, there is no need to move; instead, you can extend and create something new in an existing space.. At Keith Green Construction, we specialize in high-quality home additions for Portland-area homeowners looking to create more space, increase home value, or accommodate growing families. With over 32 years of construction experience, we bring unmatched craftsmanship and care to every project.

Whether you’re adding a new bedroom, expanding your kitchen, building a guest suite, or creating a second-story addition, we handle every step—from concept to completion—with precision and professionalism. Your addition will look like it was always meant to be there.

Why Trust Keith Green Construction for Your Home Addition?

For over three decades, Keith Green Construction has earned a reputation for integrity, transparency, and top-tier craftsmanship in Portland and the surrounding areas. Founded by Keith Green—raised in a family of carpenters and craftsmen—our company is rooted in experience and driven by a passion for helping homeowners fall in love with their homes again.

Our team will try to understand what you are after, your budget, and how you like to live. We believe in open communication, well-thought-out design, and delivering lasting results. Our dedicated team of project managers, highly skilled construction professionals, and complete office support ensures that your large-scale additions are as simple and easy as possible.

Types of Home Additions We Build

No two homes—or additions—are alike. Tailoring every project to suit the style and architecture of your existing home, allowing for all modern-day upgrades and features to be integrated without losing the story within your new space.

We specialize in:

• Suite additions
• Second-story
• Bonus rooms
• Kitchen expansions
• Attached ADUs (accessory dwelling units)
• In-law suites or guest rooms
• Covered patios and enclosed sunrooms
• Garage conversions

Seamless Integration with Your Existing Home

A poorly planned addition can feel disconnected from the rest of your home. That’s why we don’t just build at Keith Green Construction—we blend. Our team takes great care to ensure every detail—from rooflines and siding to trim and paint—matches your existing structure and enhances your home’s overall appearance and value.
We work closely with you and any necessary architects or engineers to preserve your home’s character while adding modern function and comfort. The result is a seamless transition between old and new, inside and out.

Quality, Reliability, and Guaranteed Workmanship

We’ve built our business on doing things the right way the first time. That means adhering to local codes, using quality materials, and never cutting corners—no matter the job size. Our workmanship guarantee and decades of proven expertise support every addition we build.

Our construction team is certified and experienced in everything from framing and roofing to waterproofing and insulation. We also coordinate all required permits and inspections, so you can rest easy knowing your addition is safe, sound, and built to last.

What to Expect When You Build with Us

We know a home addition is a significant investment—and a big decision. That’s why we guide you through the process with clarity, care, and consistent communication. You’ll receive a free, detailed estimate, and once the project begins, you’ll have direct access to your project manager, foreman, and salesperson.
While we don’t offer 24/7 service to the public, our active customers can always reach us during off-hours for urgent questions or project-related needs. You’re never left wondering where your project stands.

Whether you need more room for your family, a functional workspace, or a comfortable guest retreat, Keith Green Construction is ready to build the space you’ve been dreaming