How To Repair Water-Damaged Drywall
Leaks, floods, and condensation can cause cracks, crumbling, bubbling, and discoloration in your home’s drywall. If it’s wet for an extended period of time, drywall will often grow mold and mildew. Unless you’re able to dry and salvage it, replacement is necessary.
Whether you choose to hire a professional or do it yourself, repairing water-damaged drywall will look fairly similar.
Here’s how it’s done:
1. Locate Leaks
Before beginning the repair, it’s important to identify the source of the water damage. Finding pipe leaks may require the removal of drywall first. Roof leaks may require a trip to the attic during a rainstorm to trace the leak to the source. If damage has been caused by flooding, wait until the storm has passed completely and further seal the area before beginning.
2. Clear, Dry, Sanitize
If there is excess standing water, remove it as quickly as possible using a pump system. Depending on the amount of water, it may be necessary to rent a pump system or wet/dry vacuum.
Once the excess water is removed, dry the area thoroughly using high-efficiency blowers and dehumidifiers. Do this until drywall and studs are completely dry. Because mold grows well in heat, it’s best to avoid heating the area as much as possible.
A chemical sanitizer will stymie the growth of mold and deodorize the affected area. Do not use bleach, as it is dangerous to inhale and isn’t effective at killing mold.
3. Remove Drywall
Remove drywall in square or rectangle sections larger than the affected area using drywall or keyhole saw. It’s best to cut 16-inch sections (or multiples of 16 for larger areas) to the center of each stud to avoid the need for drywall clips. Be aware of wires and pipes as you cut.
4. Measure & Install
Measure the section you removed and cut an identical piece of replacement drywall (measure twice, cut once!). Insert the new drywall into the gap and secure to studs on both sides using a drywall screw every 8 inches or so.
For sections that cover outlets and switches, measure and cut openings before you attach the new piece.
5. Blend & Paint
Using mesh or paper tape (preferred by most professionals), tape the seams overlapping an inches or so at each corner. Apply joint compound in layers using a joint knife, blending into the rest of the wall 4-6 inches on each side.
Let each layer dry 12-24 hours before sanding and adding multiple layers when necessary. Once completely dry, prime the affected area before painting to seal repair.