Washington's Pacific Northwest climate creates unique challenges for homes throughout the state. Western Washington's wet, mild conditions differ dramatically from the drier eastern region, but moisture management is a concern across most of the state.
Water intrusion is Washington's primary home inspection concern. The Puget Sound region sees 150+ days of rain annually, and homes must be designed and maintained to handle constant moisture exposure. Roof condition, flashing, siding, and drainage are critical evaluation areas.
Crawlspaces require particular attention in Washington homes. Many older homes lack adequate vapor barriers, ventilation, or drainage, leading to moisture accumulation, wood rot, and mold growth. Crawlspace evaluation is a significant part of Washington home inspections.
The state's older housing stock includes many craftsman-style homes from the early 1900s with knob-and-tube wiring, galvanized plumbing, and aged foundations. More recent construction from the 1970s-1990s may have different concerns including polybutylene plumbing and dated roof materials.
Washington follows the International Residential Code with state amendments. Local jurisdictions may have additional requirements, particularly regarding moisture management and energy efficiency.
Common Washington Inspection Issues
- Moisture intrusion
- Roof wear from constant rain
- Crawlspace moisture and mold
- Wood rot
- Drainage problems
- Moss and algae growth
Local Requirements: Washington State Residential Building Code based on IRC