Drywall is the most common wall material in today’s homes. Drywall, sometimes called plasterboard or sheetrock, consists of a mineral material with a thick paper face and backer. Typically, the mineral is gypsum with or without additives to give it differing strength characteristics. Over time, the paper face of drywall can become damaged. This is especially true if wallpaper or other coverings have been added to the drywall. When those coverings are removed, the damage appears. Stains, discoloration, small bubbles, chips, and dents can make the surface of the drywall look ugly, and the damage can also make paintwork look less than perfect. How can a DIYer seal damaged drywall? Read on.
Two Steps to Sealing Drywall
The first step in preparing damaged drywall is to use a sealer. While there are many sealers on the market, specialty manufacturers produce sealer/primers specifically for drywall applications. The sealer goes on over the drywall, smoothing out imperfections and preventing the facing paper from bubbling up. Other sealers may cause that paper to wrinkle, buckle, or bubble. The special drywall sealer also waterproofs the surface, giving the drywall more ability to survive moist conditions in kitchens and bathrooms (cement board is a better option for these rooms). While this sealing step is optional, it helps ensure great looks and great performance, giving the finishing paint coat a sophisticated, professional feel.
The next step after using the special sealer is to apply skim coating. What is skim coating? It is a thin layer of drywall mud applied evenly over the entire wall surface. This drywall mud is the same joint compound professional installers use to tape the walls, but skim coating may use a slightly thinner mix of the mud.
Skim coating is applied by smoothing the joint compound on with a drywall knife or with a roller, then scraping the wall with the knife, leaving a smooth, perfect surface. It takes a bit of practice to get right, and severely damaged walls may need multiple thin coats to get to the surface perfection you desire. Once the layers are dry, paint primer and finish color coats are applied. Once you get the hang of it, skim coating can help give your home a great look while hiding damage from previous wall finishes.