We recently had a flood in our basement which was completely finished. We have two bedrooms down there which is why I want to make sure it is fixed properly. When the restoration company came in to dry everything, they cut 2 feet up the drywall, taking along with it the insulation and plastic sheet (vapour barrier). The plastic is cut the same height as the drywall, leaving no room for us to Tuck Tape it or fold it together and staple it. I am just wondering if anybody knows the best way to replace the plastic so that we can reseal the vapour barrier.
Use a Rotozip (or, like I did, a drywall cut bit in a regular rotary tool) with the depth gauge set for 1/2", so that it cuts the drywall but not vapour barrier. Cut about 2" of drywall off so you have access to enough of the vapour barrier to be able to put seam tape on it.
You may have to (carefully) cut or rip off the backing paper, but that's not a big deal.
There is a major downside to this method, if they cut exactly 2' up: you'd have to use either full sheets (wasting nearly half) or cut the sheets into 4'x2'2" pieces, still wasting 4'x18" from each sheet. Depending on the dimensions of the walls in the room, the wastage may be a deal-breaker for this method.
1) prepare the cut edge of the drywall for the joint
2) cut 1/2" wide shim strips off of wood shingles, one shim per stud
3) loosen the bottom of the drywall at each stud by removing the lowest one or two screws/nails
4) slip the shims behind the drywall, approximately horizontal, 2-4" above the bottom edge, at each stud
5) stretch very tightly a piece of 2" wide tape the length of the wall, adhesive against the studs, just below the bottom edge of drywall. this will be the 'backer' tape.
6) slip manageable lengths of 2" wide tape - adhesive facing into the room - up behind the existing vapor barrier such that 1" or so is left exposed in front of the backer tape. this will be the seam tape.
7) remove all the shims
8) install the new course of vapor barrier against the seam tape, using the backer tape for support.
9) reattach the existing drywall to the studs and install the new course of drywall