How to Install a Vapor Barrier on a Stone Foundation
- 1). Measure three inches down from the top of the stone foundation wall at each corner of the wall. Mark the location with a permanent marker. Make a second mark at the corner of each wall 18 inches from the floor.
- 2). Hold a chalk line on the marks from corner to corner and snap the line to create a straight chalk lines three inches from the top and 18 inches from the bottom of the wall across the entire wall. Repeat for each wall.
- 3). Apply double-sided fabrication tape along the bottom of each chalk line. Apply fabrication tape around all protruding plumbing, heat ducts or other breaks in the wall.
- 4). Unroll the polyethylene vapor diffuser barrier carefully. Avoid sharp objects, folding or creasing the barrier as it is unrolled to prevent punctures and tears.
- 5). Start at one corner and press vapor barrier onto the fabrication tape at the top of each wall, straighten and press onto the fabrication tape at the bottom of each wall. Use a sharp utility knife to cut the polyethylene around plumbing, heat ducts and breaks in the wall.
- 6). Use a drill with a ¼-inch masonry bit to drill holes into the stone foundation wall every three feet along the top of the polyethylene vapor diffuser barrier where it is attached the double-sided fabrication tape.
- 7). Insert expansion fasteners into each hole with a hammer. Tighten the expansion fastener by turning the nut with an appropriate size wrench clockwise until tight.
- 8). Cover the tops of all expansion fasteners as well as seams, tears, splices and punctures with seam tape.