If you have drywall with a large, damaged area, forget about patching – replacing drywall is the way to go. It’s quick, easy, and more effective in the long run, especially if the damage you’re facing is humidity or water related, because this kind of damage can weaken the entire drywall sheet. Replacing the whole thing will ensure stability and just plain look better in the long run.
1) Before you start replacing the drywall, you want to remove any trim from around the top or base of the wall you’re repairing. The only exception to this rule is with crown molding, which tends to be much more difficult to remove – instead, cut horizontally between studs, about 6 inches below or above the molding.
2) Any wall repair work that you do is going to need to span between studs, in order to ensure your wall has the required strength and long term stability needed. If you didn’t already find them because of crown molding, locate the nearest studs on either side of your damaged drywall.
3) Use a straight edge or ruler to mark out where the studs are, all the way from the floor to the ceiling. While doing this, try to take note of the approximate center of the studs, which will ensure that the both the new and old drywall have the appropriate support underneath.
Replacing the Drywall
4) With a utility knife, cut along the lines you made in the previous step. Go over it several times, since the first cut will not go through, and you don’t want to be applying pressure later on to try and make the wall piece split off. You want to cut all the way through to the studs, so continue until you’ve done this.
5) Remove this piece of drywall, and take out any old nails or screws that you can see inside the area behind the removed piece. Clean up any jagged or ragged edges – you can cut or sand to do this – while using your cut lines as a guide.
6) Your new piece of drywall should be cut to fit inside the space you removed, but the width can be about 1/16th of an inch smaller – this makes sure you aren’t forcing the new piece to fit inside. Since you’ll be mudding over the seams anyway, don’t worry if it looks awkward now.
7) Place screws or nails every 8 inches along the studs, attaching the drywall to the wall studs. This provides stability – any less will result in protruding edges and a weak fit.
8) Using a flat-edged mud trowel, apply the mud along the seams of the drywall, and feather it out to create a smooth, even surface. You can then press your joint tape into the mud, and apply another very thin layer overtop. Allow to dry for 24 hours, and apply a second coat of mud. The seams may need up to three coats, in order to cover them over completely – this is normal, however be sure to allow adequate drying time between each coat.
9) The last step in replacing drywall is to sand the mud when it has dried, getting rid of any ridges or visible edges. You can then apply a wall primer on this area, let it dry, and get ready to paint!
photo by pdz_house -CreativeCommons Attribution