Home Additions in Portland
Reimagine the entire home without starting over.
There comes a point when the house stops keeping up with the life inside it. The children need more room, dinner feels crowded, and there is no good place for an office or for guests. You love the neighborhood and have no wish to leave. You simply need more room.
A well-designed addition answers that without asking you to start over somewhere else. C&K Custom Remodeling has been building additions in Portland-area homes since 2002. Because we are a true design-build company, architecture, engineering, and construction stay under one roof, and that integration is what makes the difference when new space meets an older home.
Home Additions We Design and Build
Every good addition starts with how your family lives, so we spend time understanding your needs before any floor plan gets drawn. The directions below come up most often with the Portland homeowners we work with
- First-floor primary suites designed for comfort and accessibility.
- Second-story additions that match the existing roofline and architecture.
- Kitchen and great-room expansions that bring in more light and flow.
- Attached or detached ADUs for guests, family, or rental income.
- Bump-outs that add functional space without a full foundation.
- Sunrooms and bonus rooms that connect naturally to the rest of the house.
Real Home Addition Examples
The clearest way to understand what we build is to see it. Each project below began with a family that loved where they lived and needed the home to do more..
Changing Circumstances Downstairs Suite
Side and rear addition for single-level living
A multi-level home had always been this family’s dream, until changing circumstances made single-level living a necessity. By extending both the side and the rear of the home, we created a second primary suite on the main floor, letting them stay in the home they built without ever fighting the stairs.
Lake Oswego Home Office and Storage Addition
Two-part addition for remote work and storage
This home office addition gave the owners room to keep living and working from home whatever comes next. Paired with a second addition built for much-needed storage, the two together resolved precisely what the house had been missing.
Concordia Sunroom Addition
A light-filled room built onto the back of the home
This Concordia addition turned an underused stretch of the backyard into a sunroom built to catch light from three sides. Framed with a vaulted ceiling and wrapped in windows on every wall, the room opens to the yard through a wall of glass and a set of French doors, blurring the line between inside and out. Designed to match the scale and character of the original house, it reads as a room that was always meant to be there.
Talk to C&K about your addition
Why Homeowners Choose C&K Custom Remodeling
There are plenty of capable contractors in the Portland area. What homeowners tell us they value here is the way our design and construction work as one team, and the care that shows up where the new space meets the old.
- Master Certified credentials: Lloyd Martindale holds both the Master Certified Remodeler (MCR) and Master Certified Kitchen & Bath Remodeler (MCKBR) designations, credentials held by fewer than 1% of contractors nationwide.
- Two decades of additions: specialized work since 2002, on everything from Craftsman bungalows to mid-century homes.
- Our own crews: full-time carpenters, not rotating subs, and that consistency shows in the finish work.
- Additions that belong: the work is to make new space look like it has always been there.
- Materials built for wet use: higher-end tile detail and cabinetry that hold up to daily exposure.
- A track record you can verify: two decades of 5-star reviews from Portland-area homeowners and a Houzz rating of 4.9 out of 5, and Buildzoom score that places us in the top 2% of Oregon contractors.
Home Addition Costs in Portland
There is no single number for a Portland addition, because a bump-out and a full second story share almost nothing in scope. What a project costs comes down to a few clear factors: how much new structure is required, the level of finish you choose, how much the existing systems need upgrading, and the site and engineering conditions of your lot.
Typical investment ranges at C&K:
- Small Addition: $50,000–$150,000. Bump-outs, sunrooms, and single-room additions that work within the existing structure
- Mid-Size Addition: $150,000–$350,000. Primary suites and larger ground-floor additions with a full foundation.
- Large Addition: $350,000+. Second-story additions and detached ADUs with full structure and systems.
Why a Home Addition Is Great Investment
Beyond the room it adds to daily life, a well-built addition is one of the soundest ways to invest in a Portland home you already love and intend to keep.
- Square footage where it counts: adding livable, permitted space raises both how the home lives and how it appraises, especially in established neighborhoods.
- A smarter move than relocating: staying and adding on often costs less, all in, than buying up in the same neighborhood and starting over.
- Value that holds when it belongs: an addition that matches the original architecture reads as part of the home, which is what protects its value at resale.
The 6-Step Process
This is a big decision, and the uncertainty can be the stressful part. Our process is built to keep the path visible, so you always know what is happening and what comes next, with regular updates throughout.
- Initial consultation: we talk through what you need and what your lot will allow.
- Preconstruction assessment: zoning, setbacks, and site conditions checked before design begins.
- Design development: we explore options until we land on a design that fits your home and your budget.
- Permits and approvals: we handle the drawings, engineering, and city submissions.
- Construction: our own crews and trusted trades work through the build with regular updates.
- Final walkthrough: we go over every detail together before the project is closed out.
Talk to C&K about your home
Considerations for a Home Addition
A lot of contractors treat additions like large remodels. They are not. An addition has to become part of the house it joins, in structure, in appearance, and in the systems that run through it. When floor heights do not match, when rooflines look awkward, or when the heating cannot keep up, the cause almost always traces back to decisions made early.
The considerations that shape a successful addition:
- Blending with the original home: rooflines, eaves, windows, and siding matched so the addition reads as part of the house, not a thing attached to it.
- Foundation and structure for Portland: engineering built for local soil and seismic requirements, with proper connections where new meets old.
- Systems sized from the start: HVAC, electrical, and plumbing planned for the larger home, not stretched to cover it after the fact.
- Zoning and approvals handled upfront: setbacks, historic-district rules, and tree preservation resolved during design, so the plans we submit are realistic and buildable.
On timeline: smaller bump-outs and single-room additions move faster, while second stories and detached ADUs take longer once permitting and engineering are factored in. Most projects run several months from design through completion, and you have a realistic schedule in hand before you commit.
FAQs About Home Additions
Will my addition need a structural engineer and an architect?
Most do. The advantage of working with us is that our design and construction teams collaborate from day one, so the engineering and the buildability are worked out together rather than handed back and forth.
Can I stay in my home during construction?
Yes, in most cases. Because an addition adds on rather than gutting the interior, most families are able to stay put through the build.
What is the difference between a home addition and an ADU?
A home addition expands your main living space. An ADU is a separate living unit with its own kitchen, bathroom, and entrance, either attached or detached.
Should I add on or just move?
If you love your location and the character of your home, adding on is often the smarter move, financially and otherwise. A consultation is the fastest way to know whether your home and goals make it the right call.
Service Area
We build home additions throughout the Portland neighborhoods where homeowners take their homes seriously, where the architecture is worth matching and the investment is in a home they plan to keep.
Portland · Lake Oswego · West Linn · Dunthorpe · NW Portland · West Hills · Beaverton · Tigard · Tualatin
See what C&K can do for your Home Additon
