Go Far®ADU & DADU builder · Mountlake Terrace
ADU & DADU builder for Mountlake Terrace.
Light rail changed the math in Mountlake Terrace: a second unit a short walk from the station is about as strong as the rental case gets in Snohomish County, and Washington’s ADU law now guarantees the right to build one on most residential lots. Go Far Construction builds permitted, finished ADUs across Mountlake Terrace — ground-up backyard cottages, attached in-law suites, and garage conversions — from a family-owned, licensed Washington general contractor based next door in Lynnwood.
Washington’s ADU law — HB 1337 — sets the statewide floor cities had to meet by mid-2025: two accessory units allowed on most residential lots, no owner-occupancy requirement, and ADUs of at least 1,000 square feet permitted. The same law bars cities from requiring off-street ADU parking within a half-mile of major transit — a circle the Link station puts a large share of Mountlake Terrace inside. What fits on your parcel still comes down to zoning, lot coverage, and setbacks, so we confirm the numbers with the City of Mountlake Terrace before design begins. Our ADU vs. DADU guide walks through which route fits which lot.
On budget: basement ADU conversions and garage conversions in this market generally land between $100,000 and $250,000 depending on the starting condition of the space, while a new-build detached cottage typically runs $250,000 to $450,000 including site work, utilities, and soft costs. The full math lives in our ADU cost guide and DADU cost guide, and ADU financing options covers how owners fund the build. In Mountlake Terrace the rental case is unusually direct — a stand-alone unit minutes on foot from a 28-minute train to downtown Seattle — and the family case is just as common: a parent’s cottage or an adult child’s first apartment, steps from the main house.
We build every route to a second unit: garage conversions, attached mother-in-law suites, and ground-up DADUs in the workable backyards of the original plats. Permits run through the City of Mountlake Terrace; we prepare the application, carry fees in an itemized written price, and meet every inspector on site, as on all our Mountlake Terrace projects.
What we build in Mountlake Terrace
Mountlake Terrace ADU questions
How much does it cost to build an ADU in Mountlake Terrace?
Garage conversions and interior conversions generally land in the $100,000–$250,000 range depending on the starting condition of the space. A new-build detached ADU (backyard cottage) typically runs $250,000–$450,000 including construction, site work, utility connections, and soft costs. Every project gets an itemized written estimate before design is finalized.
How many ADUs does Mountlake Terrace allow on a lot?
Washington’s statewide ADU law, HB 1337, required cities to allow two accessory units on most residential lots by mid-2025, with no owner-occupancy requirement. Exactly what fits on your parcel depends on zoning, lot coverage, and setbacks, so we confirm the numbers with the City of Mountlake Terrace before design begins.
Do I need parking for an ADU near the light rail station?
Within a half-mile of a major transit stop, Washington’s ADU law bars cities from requiring off-street parking for an ADU — and the Link station puts a large share of Mountlake Terrace inside that circle. Outside it, state law caps what can be required. We confirm your lot’s exact numbers with the city during feasibility.
Do you handle the Mountlake Terrace permits and inspections?
Yes — we prepare the City of Mountlake Terrace application, include permit fees in your itemized written estimate, and meet every inspector on site from foundation to final.
Plan your project
Planning a Mountlake Terrace ADU? Useful next reads: ADU costs · DADU costs · Washington’s ADU law · ADU financing · our Mountlake Terrace page · all of Snohomish County