Get matched with top plant watering pros in Bath, MI

Yes, you can install drywall over plaster, but there are important factors to consider. While it can create a smooth, flat surface, it is often not the best approach. Installing drywall over plaster will increase the wall's thickness, which can cause issues with existing window and door frames that may no longer fit. You might also need to adjust power outlets to keep them accessible. A better, though more expensive, option is to remove the old plaster and lath entirely before installing new drywall. Drywalling directly over plaster seals in the old material, and if any problems arise later, you will need to remove both layers down to the structural beams for repairs. Given the potential complications, this job is best handled by professionals.

You should leave a gap between drywall sheets because they naturally expand and contract along with the building framing as temperature and humidity change. Most pro drywall installers leave a gap of about ⅛ inch between drywall sheets, allowing the sheets to expand, contract, and shift without cracking or becoming damaged. If you don’t leave enough gaps between slabs, the edges will press against each other when they expand, and the pressure can cause visible cracks.

While a normal moisture level for drywall is between 5% and 12%, replacement is recommended if you get consistent readings above 17%. At this level, the drywall is likely too compromised by extensive moisture damage to be considered safe. You can replace either the entire sheet or just the affected section. If you are unsure after a visual inspection, it is best to have a contractor or water restoration provider use a professional moisture meter to get an accurate reading.

To hide drywall edges, you need to properly apply drywall tape and multiple layers of joint compound. These materials hide the seams between drywall sheets and fill the holes from drywall screws, leaving behind a smooth, flat finish to paint over. Apply joint compound smoothly, and finish the job by sanding the walls to make sure you fully hide drywall edges and other imperfections.