Beaverton Home Additions

An addition done right blends into the house you already own

An addition expands the home you already have — unlike an ADU, which is a separate unit — and the real craft is making the new space look like it was always there. JDI Construction is a family-owned, Vancouver-based design-build remodeler, and on an addition our work is really two jobs at once: building the new space, and marrying it to the existing foundation, roofline, and walls. In Beaverton that means working across a genuine mix of housing — the mid-century ranches spread through the older Washington County neighborhoods and the newer subdivisions filling in around the Sunset Corridor — each of which adds on a little differently. Because an addition shares the roof, systems, and foundation with the main house, it grows what you own rather than dropping a separate building in the yard.

Our designers and trades work as one team, so the addition you approve is drawn to tie into the house that's actually there — we don't hand a set of plans to a separate crew and hope the new roof and foundation line up. Here's how additions come together, the calls worth making early, and what shapes cost and timeline.

Types of additions we build

"Addition" covers a lot of ground, from a few extra feet to a whole new floor, and the right one depends on your lot, your budget, and how the house is built:

A few decisions worth making early

An addition rests on a few decisions that come before design. The first is up or out: pushing outward is usually simpler and less expensive when the lot has room, which many of Beaverton's ranch-style properties do, while going up a story preserves the yard but means confirming the existing foundation and framing can carry the added load. The second is how much the current home can support — whether the foundation, the electrical panel, and the heating and cooling system can serve the new space or need upgrading as part of the project. The third is what the parcel itself allows: setbacks, lot-coverage limits, and height rules that vary by jurisdiction and, in the newer subdivisions, often by HOA. We work through all of it up front so the plan fits the house, the lot, and the budget.

What Beaverton homeowners add on for

Most additions we build in Beaverton come down to needing more of the home you already have rather than moving out of a neighborhood that works: a primary suite, another bedroom or two, a larger family room, or a dedicated home office. Because it's attached and shares the roof, systems, and foundation with the main house, an addition keeps everything under one roofline instead of becoming a separate structure the way an ADU would.

The matching challenge shifts with the home's age. On the mid-century ranches, the trick is honoring the original low horizontal lines and finding siding and trim that read as period-correct rather than obviously new. In the newer Sunset Corridor subdivisions, the materials are easier to match but the design usually has to answer to HOA guidelines and tighter lot-coverage limits. Either way, we treat the seams — foundation, roofline, exterior skin, and interior transitions — as the part that decides whether the addition looks original or added on.

What does a home addition cost in Beaverton?

Addition cost is driven first by type: a bump-out that borrows from the existing structure is far less than a second-story addition that requires reinforcing the foundation and framing below it. After that it's size, how much structural work the tie-in requires, how hard the existing materials are to match, and whether the systems need extending or upgrading. Because our design and our trades are both in-house, we can price the structural realities honestly up front and give you an itemized estimate once the addition is drawn, so the number reflects your house and your lot rather than a generic per-square-foot figure.

How long does a home addition take?

An addition is a months-long project more than a weeks-long one, because it runs through design and engineering, permitting, foundation and framing, tying into the existing structure, and then finishes. Second-story and structural additions take longer than a simple bump-out. We give you a realistic schedule before demolition, handle the engineering and permits the work requires, and sequence it to keep the existing home weather-tight and livable while the new space goes up.

Why homeowners in Beaverton choose JDI

An addition is where design-build earns its keep, because the design, the structural engineering, and the construction all have to agree for new and old to meet cleanly. As a single accountable team, we handle the plans, the load paths, the tie-in, and the finishes under one roof, so nothing falls through the gap between an architect and a separate builder. We manage the permitting, keep you updated through our client portal, and stand behind the work with a five-year workmanship warranty. JDI is just across the river in Vancouver, a short drive from Beaverton, so we're close enough to be on-site and responsive throughout a project this involved.

JDI Construction — "Built by family. Trusted by neighbors." Design-build remodeling and home additions based in downtown Vancouver, WA, serving Beaverton and the greater Portland–Vancouver metro since 2007.