Sehome climbs the hill below the Sehome Hill Arboretum, between downtown and Western, and the slope is what defines it for ADUs. Homes built into a hillside almost always have a daylight basement, where one side opens out at grade. That is the best basement you can convert, because the walk-out side already gives you a real entrance and natural light instead of a dark below-grade box. Walk-out suites and basement apartments are the natural project here.
The work is still real, though. Any bedroom in the unit needs a code egress window, ceiling height has to check out, and our wet climate means the moisture and ventilation system is not optional on a below-grade space. Sehome's sloped lots also mean drainage matters, so water moves down the hill and away from the foundation instead of into it. We run a free feasibility check on the basement and the grade, handle the egress and moisture work, pull the permit with the City, and build to current energy code.
ADU costs in Sehome depend on the type. A ground-up detached backyard cottage runs $250,000 to $400,000 or more, a garage conversion runs $80,000 to $150,000, and a basement apartment conversion runs $90,000 to $180,000. The drivers are size, finish level, site access, and how far we run utilities to the unit. We give you a line-item number after a free site visit, so you know exactly what your project costs before you commit.
Do you build ADUs in Sehome?
Yes. Sehome is one of our core service areas, and we build backyard cottages, garage conversions, in-law suites, and basement apartments here. We start every project with a free feasibility check against your lot size, setbacks, and the City of Bellingham rules, so you know what your lot allows before you spend anything on design.
Who handles the permit for an ADU in Sehome?
We do, start to finish. Sehome is inside Bellingham city limits, so your basement conversion runs through the City of Bellingham. We handle the egress permit and the inspections. We assemble the full permit package, manage the review including answering reviewer comments, and carry it through to an approved permit, then handle the inspections during the build.
Ready for a free Sehome feasibility check?
Tell us about your lot and your goal. We'll reply within 15 minutes during business hours.