Crawl Space Mold Removal in Gig Harbor, WA

Our Gig Harbor house isn't old. How did the crawl space get moldy?

Age helps less than people expect. Census-derived figures put the median Gig Harbor home at 1996, and plenty of houses from that period were framed over vented crawl spaces with thin plastic laid on the dirt. Over twenty or thirty winters that plastic tears, gets pushed aside by plumbers and cable installers, or ends up buried under mud. Once bare soil is open to the space, moisture rises into the air below the floor, settles on the coolest wood and stays there from fall through spring. Fiberglass batts between the joists soak it up and hold it against the subfloor. The first sign upstairs is often a stale smell in a hallway or bedroom closet.

Our lot slopes toward the house. Does that matter?

Often it is the main cause. Gig Harbor sits on the shore of its bay on the Gig Harbor Peninsula, and the city's critical areas code regulates landslide, erosion, bluff and ravine hazard areas along with flood hazard areas, which tells you how much of the town is built on grades. On a hillside lot, rain soaking into the uphill yard can move through the soil and seep in along the foundation wall, leaving mud lines or puddles on the ground cover after a long storm. Downspouts that empty right at the footing add more. A careful company will look at the outside grading and gutters, not just the wood, and may suggest a drainage contractor if water is getting in faster than any ground cover can handle.

What should the cleanup actually include?

• A full crawl of the space with moisture readings taken in the joists, beams and sill plates.
• Wet or moldy batts bagged and carried out, not left in place.
• Growth cleaned off the framing by scrubbing, sanding or blasting, then time for the wood to dry.
• A new ground cover with taped seams once standing water is dealt with.
• No sealant or paint sprayed over wet, moldy wood; EPA warns that covering mold does not fix it.

Washington has no state mold license or certification, so confirm the company is registered with Washington L&I as a construction contractor on L&I's Verify a Contractor tool before signing.

A local note on repairs

If rot is found and joists, a sill plate or subfloor have to be replaced, building permits inside city limits come from the City of Gig Harbor Building & Fire Safety Division, including repair permits through its online portal. The Tacoma-Pierce County Health Department's Healthy Homes program offers mold resources, and the Washington Department of Health has a statewide mold page.