Commercial Mold Remediation in Seattle, WA

Typical Seattle commercial calls

Fewer than half of Seattle homes are owner-occupied, so much of the city's mold work happens in multifamily buildings rather than single houses. Common situations include:

• Apartment and condo buildings where one unit's leak has crossed into a neighbor's wall or ceiling
• Older brick and wood-frame buildings in areas like Capitol Hill or Queen Anne with roof, parapet or window leaks after a long rainy stretch
• Shops, studios and warehouses near the Duwamish Waterway or Ship Canal with damp slab floors or water intrusion at grade
• Offices, clinics, churches and schools with stained ceiling tiles or a musty mechanical room

Step one: a written scope

Before any work, ask for a document that measures the affected area, names the materials coming out, explains how the area will be isolated, and states how the company will show the job is finished. EPA's commercial guide groups jobs by size, roughly under 10 square feet, 10 to 100, and over 100, with stronger containment and protective equipment as size goes up. It also notes that judgment matters: dense growth in a small room can be worse than scattered spots across a large one.

Shared air and building systems

EPA says not to run an HVAC system you know or suspect is contaminated, because it can spread mold through the building. In an office or apartment building with central air handling or shared exhaust, that is a decision for the owner and facilities staff before demolition begins. Few Seattle buildings rely on central cooling, but ventilation systems, rooftop units and corridor supply air still need to be checked.

Occupants, notice and rental rules

Tell occupants what is happening, which areas are closed and for how long, and plan around anyone with asthma or a weakened immune system, who EPA says should stay away from moldy areas. Seattle rental buildings fall under SDCI's Rental Registration and Inspection Ordinance, whose checklist looks for weathertight, damp-free buildings, working bath fans and no leaking plumbing. Washington landlords must also give tenants DOH-approved mold information and start repairs within set times after written notice. This is general information, not legal advice.

Bids, registration and clearance

Commercial jobs are bid per project. Angi's Seattle cost guide, about $10 to $25 per square foot, reflects residential work, so treat it only as a rough reference. After-hours scheduling, lifts or ceiling access, HVAC cleaning and the amount of build-back all raise the price. Washington has no state mold license, so check that each bidder is registered with L&I as a construction contractor, get bids in writing, and consider an independent assessor to confirm the area is clean before rebuilding.