How to Box in Exposed Duct Work
- 1). Pull a length of hanger strap long enough to wrap the duct. Cut the strap with tin snips.
- 2). Nail one end of the strap to the top plate -- the piece of lumber that spans the top of the wall studs -- of the wall behind the duct. Pull the other end of the strap around the duct, and nail it near the first end. Place a hanger strap every few feet to hold the duct in place.
- 3). Nail a support row of 2 x 4s beneath the duct; the boards should run parallel to the duct and perpendicular to the wall joists. Nail a second support row of 2 x 4s along the ceiling, parallel to the duct and perpendicular to the ceiling joists. The support rows should be about 12 inches from the ceiling and wall, respectively.
- 4). Cut a 2 x 4 into 12-inch pieces. Nail a 12-inch piece to the ceiling support row at 24-inch intervals so that the piece extends down into the room. Nail a hanging 2 x 4 support row to the bottom of the 12-inch pieces, wide side to wide side.
- 5). Nail 12-inch horizontal pieces to connect the wall support row to the hanging support row at each downward-hanging piece to form a box.
- 6). Cut drywall to cover the vertical and horizontal sides of the box. Hang the drywall by driving nails through the drywall at the boards forming the box. Attach corner bead along the outside corner of the box.
- 7). Apply a thin coat of joint compound along all seams using your drywall knife. Press a strip of drywall tape into the compound along the seams. Apply a second coat of compound, scrape away the excess, and let the mud dry overnight. Apply two additional coats of compound, let them dry, then sand with medium-grit sandpaper to smooth. You can then paint your box.
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