Black Mold Removal in Shoreline, WA

Why does my Shoreline house keep growing dark mold?

Age is a big part of it. The median home in Shoreline was built in 1968, so many houses have original windows, bath fans that were never ducted outdoors, thin wall insulation and vented crawl spaces. From fall through spring, warm indoor air hits those cold surfaces and condenses. Window sills, the corners of exterior closets, bathroom ceilings and the underside of the floor are where the black spots show up first. Fixing the moisture, whether that means a new fan, better attic venting or a crawl space vapor barrier, is what keeps it from returning.

Does living near Boeing Creek, Thornton Creek or the Sound change anything?

It can. Shoreline maps floodplains along its 3.4 miles of Puget Sound shoreline and along Boeing Creek and Thornton Creek, and the city takes part in the National Flood Insurance Program. Homes in those areas are more likely to see groundwater or surface water in crawl spaces and lower floors. If a remediation job turns into rebuilding inside a FEMA-designated floodplain, the city requires a Floodplain Development Permit for development there, and federal flood insurance applies when federal loans are used to buy or build. General permits for interior remodels sit with Shoreline Planning & Community Development.

How do I pick a company, and what will it cost?

Washington DOH says there is no state certification for mold work, so look for a company registered with Washington L&I as a construction contractor, verify it on L&I's tool, and get written bids from more than one. Angi's Seattle cost guide reports a typical job at $1,008 to $2,967, a crawl space at $425 to $1,650 and an attic at $825 to $3,300. Square footage, access and rebuild work move the price far more than the color of the mold. Ask each company how it will contain the area and how it will show the job is done.

A note for Shoreline renters

Public Health - Seattle & King County does not do mold assessments. It tells tenants to notify the landlord in writing about leaks or moisture and to report the unfixed water or maintenance problem to local code enforcement. In Shoreline, that's the Code Enforcement and Customer Response Team.