Roof Expansion Joint Flashing: Covers and Details

Our joint covers are made from a soft lead composition. This material is chosen for its unique flexibility and ability to 'creep' or deform slightly to accommodate building movement without failing. It is highly durable, corrosion-resistant, and naturally oxidizes to a neutral grey color that blends seamlessly with masonry.

Weathercap covers the sealant, shielding it from UV radiation, rain, and other environmental stressors that cause degradation. It also reduces the effective opening size of the joint, which lessens the strain on the sealant and helps prevent 'margin checking' or failure at the edges, significantly extending the sealant's service life.

Absolutely. Weathercap is ideal for historic restoration and is specified in the GSA's Historic Preservation Technical Procedures. Its soft lead material and performance characteristics are perfect for protecting aging, vulnerable masonry. It has been successfully used on numerous national landmarks, including the Washington Monument and the U.S. Supreme Court.

The types refer to the joint's geometry. Type A is a flat cap designed for joints between masonry units on the same plane, such as the top cross-joints of a stone coping. Type B is a 90-degree cove cap used for right-angle joints, like where a horizontal cornice meets a vertical wall or a window sill joins the surrounding masonry.

All our Weathercap joint flashing products are consistently supplied in standard 6-foot lengths. This allows for easy transportation and handling on the job site and provides ample length for cutting and fitting to specific joint requirements for various architectural applications, from small window sills to long parapet walls.

Yes, our lead flashing can be painted to match any adjacent materials or to meet specific aesthetic requirements of an architectural design. While it naturally oxidizes to a neutral grey that complements most masonry, painting provides an additional layer of customization for both new construction and historic restoration projects.