Moisture barriers · Olympia, WA
Olympia moisture barriers for the long wet season
More rain means more ground moisture under your floor. A sealed, continuous moisture barrier is the first line of defense for an Olympia crawl space.
- Look for condensation on ducts and pipes
- Fit barrier around mixed foundations and old piers
- Discuss full encapsulation for the wettest crawl spaces
Moisture barriers for Olympia homes · Kent, WAOlympia homes
Moisture barriers built around Olympia houses
Olympia's extra rainfall shows up under the house. The soil in a crawl space soaks up water through the long wet season and releases it as vapor into the framing above, especially where the ground is bare or covered by torn, partial plastic. On low lots near Budd Inlet, Capitol Lake or the Deschutes, and in neighborhoods where the water table rises in winter, that moisture load is heavy. Signs include condensation on ducts and pipes, damp or sagging floor insulation, a musty smell and mold spotting on the joists. A continuous barrier, sealed at every edge, cuts that moisture off at the source.
Installation is careful, not quick. We clear debris and old plastic, rake the soil, and lay heavy polyethylene across the entire floor. Seams overlap and are taped, the sheet is fastened up the foundation walls, and posts and piers are wrapped. In older homes with mixed foundations, we fit the barrier around every pier and step. For wetter Olympia crawl spaces, we also talk through encapsulation, which seals the vents and walls so the space can be kept dry year-round. Where water pools, we address drainage first, because a barrier stops vapor, not flowing water. You get photos of the finished crawl space.
- Look for condensation on ducts and pipes
- Fit barrier around mixed foundations and old piers
- Discuss full encapsulation for the wettest crawl spaces
- Fix pooling water before laying any barrier
Local conditions
What Olympia throws at attics and crawl spaces
The houses
Olympia's oldest homes sit close to the Capitol. The South Capitol neighborhood, Bigelow Highlands and parts of the Eastside and Westside are full of Craftsman bungalows, cottages and a few Victorians from the 1890s through the 1930s, many on post-and-pier or early concrete foundations with low crawl spaces and partial basements. Post-war ramblers and 1960s and 1970s split-levels fill much of the Eastside and Northeast. The Westside and Cooper Point areas add newer subdivisions from the 1980s through the 2000s, with truss attics, vaulted ceilings and blown-in insulation.
The weather
Olympia gets noticeably more rain than Seattle, and the wet season runs long. The city wraps around the south end of Budd Inlet, where the Deschutes River meets salt water, and fog settles in the low areas on fall and winter mornings. Clear winter nights often turn colder here than in Seattle, so frost forms on roofs and inside poorly ventilated attics. Heavy fir and maple canopy keeps many lots shaded and damp.
The wildlife
Norway rats are common along the Budd Inlet waterfront, the port area and downtown, and they move into crawl spaces from there. Roof rats and squirrels use the dense tree cover in older neighborhoods to reach rooflines. Wooded areas such as Priest Point Park and Watershed Park bring raccoons and other wildlife close to homes, and ravines give rodents shelter right behind backyards.
Typical results
What moisture barriers looks like
BeforeAfterHow it works
Same crew, same standard, in Olympia
- 01
Inspect inside and out
- 02
Trace each water source
- 03
Fix the barrier and the vents
- 04
Get roof water away
- 05
Recheck and photos
FAQ
Moisture barriers in Olympia: FAQ
Still unsure? Call (800) 674-4933 and talk it through with us.
Should I choose a vapor barrier or full encapsulation?
A sealed vapor barrier is the right baseline for most Olympia homes. Encapsulation goes further, sealing the vents and walls so the crawl space can be kept dry. It is worth considering if the space stays damp even with a good barrier, or if ducts and equipment are down there. We explain both and recommend based on what we find.
Can a moisture barrier go down if my crawl space is wet right now?
Not over standing water. If there is pooling, the source needs to be fixed first, usually gutters, downspouts or grading. Damp soil is fine to cover once standing water is gone. We photograph the conditions and tell you what needs to happen before installation.
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Free moisture barriers inspection in Olympia.
Book a free inspection. We'll photograph your attic and crawl space and walk you through what we find, before you decide anything.