Home Remodeling in Bellingham

One Bellingham home in six was built before 1940

The Census Bureau's 2020-2024 American Community Survey counts 43,792 housing units in Bellingham. Of those, 7,462 were built in 1939 or earlier, while 13,742 date from 2000 or later. The median year built is 1986 overall and 1980 for owner-occupied homes, and 44.6 percent of homes are owner-occupied. In the older houses, plan for what opening a wall reveals. Bellingham's exemption for ordinary repairs stops at cutting walls, beams or piping.

Source: Census ACS 2020-2024, B25034 year structure built, Bellingham

Homes that drain to Lake Whatcom face the strictest rules in the city

The city treats the Lake Whatcom watershed as a critical basin, and all land in city limits that drains to Basin One falls under BMC 16.80 and special stormwater standards. No clearing, grading, filling, excavating or trenching is allowed from October 1 through May 31 without written approval. A project adding 120 square feet of hard or partly pervious surface, or disturbing 500 square feet of land, needs stormwater mitigation, and the largest projects must hold phosphorus runoff to 0.15 pounds per acre per year. The city also restricts fertilizer and other materials that contain phosphorus there under BMC 15.42.050.

Source: City of Bellingham, Lake Whatcom Stormwater Guidance

Bellingham has allowed ADUs since 1995

Bellingham passed its first accessory dwelling unit ordinance in 1995. Today a lot can have two ADUs of up to 1,000 square feet each, with no parking and no owner occupancy required, and an ADU can even be sold as a condominium. Both a land use permit and a building permit are needed, and most ADUs go through the streamlined Type I staff review. ADUs are allowed anywhere residential building is, except in the Lake Whatcom watershed.

Source: City of Bellingham, Accessory Dwelling Units

How much does a remodel cost in Bellingham?

Federal wage data shows Bellingham trades are expensive. In May 2025 the median plumber earned $49.40 an hour and the median electrician $46.92, both more than 50 percent above national pay, while carpenters earned $35.22. The median Bellingham home was worth $627,500 in the 2020-2024 Census survey. Permit fees are calculated from the project valuation, and the city publishes a fee calculator.

Do I need a permit to remodel in Bellingham?

For most remodels, yes. Bellingham requires permits to alter or repair a building and to change electrical, gas, mechanical or plumbing systems. Finish work such as painting, tiling, cabinets and countertops is exempt, and house alterations worth $1,500 or less in six months are exempt from the building permit, though never from trade permits.

Can I build an ADU in Bellingham?

Yes, anywhere residential building is allowed except the Lake Whatcom watershed. A lot can have two ADUs of up to 1,000 square feet, with no parking and no owner occupancy required. You need both a land use permit and a building permit, and most ADUs go through the fast Type I staff review. An ADU can even be sold as a condominium.

What are the building rules in the Lake Whatcom watershed?

Land in Bellingham that drains to Basin One of Lake Whatcom is a critical basin. No clearing, grading or digging is allowed from October 1 through May 31. Adding 120 square feet of hard surface or disturbing 500 square feet of land triggers stormwater mitigation, larger projects must limit phosphorus runoff, and ADUs are not allowed there.

When do I need a stormwater permit in Bellingham?

Citywide, Bellingham requires a stormwater permit when a project creates or replaces more than 300 square feet of impervious surface, or disturbs more than 500 square feet of land. In the Lake Whatcom watershed the bar drops to 120 square feet of hard or partly pervious surface, and projects of 5,000 square feet or more need a fully engineered plan.