first_imgIn three new videos produced by Oregon builder Hammer & Hand, lead carpenter Val Darrah explains how he keeps air sealing in mind as he frames the walls for his current project, the Pumpkin Ridge Passive House.Val explains why he prefers to use a router rather than a saw when he cuts out window openings in the OSB sheathing. He also shares his method of building window bucks out of 3/4-inch plywood.The OSB sheathing seams are treated with Prosoco R-Guard products: Joint and Seam Filler for the seams, and FastFlash for the inside of the window rough openings. Val explains that in damp weather, it’s easier and more effective to seal sheathing seams with Joint and Seam Filler, a moisture-cured sealing product, than with air-sealing tape.The concrete foundation will be insulated on the exterior with 6 inches of expanded polystyrene (EPS) foam. For more information on the Pumpkin Ridge Passive House project, visit this page on the Hammer and Hand website.last_img read more