Bone dry roofing — Seattle, WA

For Seattle's climate, EPDM (ethylene propylene diene monomer) is a common and highly effective single-ply rubber roofing membrane. It's known for its exceptional resistance to UV rays, ozone, and extreme temperatures, making it ideal for flat or low-slope applications common in some Seattle architectural styles. TPO (thermoplastic polyolefin) is another durable option, offering good reflectivity and puncture resistance. Both provide excellent waterproofing, crucial for managing the city's frequent rainfall and ensuring a bone dry outcome.

While a wide array of metal roof colors are available, lighter shades can help reflect solar heat, potentially reducing cooling costs during Seattle's warmer months. However, darker colors can absorb more heat, which might be beneficial in winter. The primary consideration for Seattle should be the quality of the paint finish, typically a Kynar 500 or Hylar 5000 coating, which offers superior fade resistance and protection against UV degradation and the corrosive effects of salt air if near Puget Sound. This ensures a bone dry, long-lasting finish.

Roofing tar, or asphalt-based sealant, is primarily used in Seattle for specific applications, such as sealing small cracks, joints, or around penetrations like vent pipes on certain roofing systems. It's often employed as an adhesive for some types of underlayment or as a caulk for flashing details. However, for primary roofing membranes, modern synthetic sealants and adhesives are generally preferred for their superior flexibility, durability, and longevity in the region's variable weather conditions, ensuring a bone dry seal.