Washougal ADU Builder

An ADU is a full building, not just a room out back

An ADU is a real building with its own kitchen, bath, and utilities, which is why the site work and connections drive as much of the cost as the walls do. JDI Construction is a family-owned, Vancouver-based design-build remodeler, and we treat an accessory dwelling unit as a second, independent home — so we begin by confirming what your specific Washougal property actually allows before we design anything. That matters more here than most people expect: Washougal is a small river town at the mouth of the Columbia River Gorge, with hillside parcels and larger lots that can bring grade, access, and utility runs into the conversation early.

Our designers and trades operate as one team, so the unit you approve is already grounded in what the site and the code permit — we don't hand a hopeful floor plan to a separate crew and learn later that it won't pass. Here's the range of ADUs we build, what determines what's possible, and what to expect on cost and timeline.

What decides what you can build

A few factors settle what's possible on your lot long before design starts:

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   Zoning & size limitsWhat your lot's zone allows for a second unit — in size, height, and placement.
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   Setbacks & coverageHow close to property lines and how much of the lot a unit can occupy.
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   Parking & accessWhether parking is required and how the unit is reached from the street.
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   Utilities & feesSewer, water, and power connections, plus the system development charges that come with them.

A few decisions worth making early

The choices that make or break an ADU come well ahead of design. The first is feasibility: ADU rules — size limits, setbacks, height, parking, and fees — are set by the jurisdiction, and in Washougal those are Washington's and the city's or Clark County's, not the rules that govern Portland across the river. We confirm what your specific lot permits before drawing. The second is type and use: a garage conversion, a basement unit, an attached addition, and a detached cottage carry different costs and site demands, and Washougal's sloped and larger lots often shift that calculation — a hillside site can turn a simple detached build into a grading-and-access project. Whether the unit is a rental, family housing, or a workspace also shapes the layout. The third is budgeting for the invisible parts — the sewer, water, and power connections and the system development charges that come with a new dwelling. We walk through all of it up front.

What Washougal homeowners build ADUs for

Most ADUs we discuss in Washougal serve one of a few roles: a rental for added income, a private space for aging parents or grown children, or a home office or studio kept separate from the main house. Each points the design a different direction — a rental toward durability and its own entrance, a multigenerational unit toward single-level accessibility, a studio toward daylight and quiet.

Because Washougal sits in Clark County, the applicable rules are Washington's and the city's or county's, which differ from Portland's across the Columbia — a reason we confirm what your parcel allows rather than assume. And on the larger, sometimes sloping lots common here, a detached cottage is frequently a natural fit. Whatever the use, we design the compact footprint to live larger than its square footage, with the light, storage, and ceiling height that keep a small home from feeling small.

What does an ADU cost in Washougal?

ADU cost starts with type: a garage or basement conversion that reuses an existing structure generally costs less than a detached cottage built from the ground up. After that come size and finish level, and then the piece homeowners routinely underestimate — the site and utility work, which carries extra weight on Washougal's hillside and larger parcels. Running sewer, water, and power to a new dwelling, handling grading and access on a sloped lot, and covering connection fees can be a meaningful share of the budget, so we scope them early. With design and trades both in-house, we give you an itemized estimate once we know what your lot allows and which type fits, rather than a generic per-square-foot number.

How long does an ADU take to build?

An ADU runs on three clocks: feasibility and design, permitting, and construction. Permitting for a second dwelling can take longer than a remodel because it involves zoning and utility review, so we build that time into the plan rather than promising a fast turnaround. Once permits are in hand, construction depends on the type — a conversion is quicker than a ground-up cottage, and a sloped Washougal site can add site-prep time to a detached build. We give you a realistic schedule after the feasibility check, handle the permitting, and keep you updated through our client portal as the unit comes together.

Why homeowners in Washougal choose JDI

An ADU rewards a builder who understands the rules as well as the construction, because the project can stall at the permit counter long before the first wall goes up — and on Washougal's steeper lots, the site itself adds its own demands. As a single accountable design-build team, we handle the feasibility, the design, the utility connections, and the build under one roof, so nothing gets lost between a zoning question and the crew on site. We manage the permitting, keep you informed through our client portal, and back the work with a five-year workmanship warranty. Just across from neighboring Camas and a short drive from our Vancouver base, we're close enough to stay responsive throughout.

JDI Construction — "Built by family. Trusted by neighbors." Design-build remodeling and ADU construction based in downtown Vancouver, WA, serving Washougal, Camas, and the greater Clark County–Portland metro since 2007.