Painting a wall that has any sort of mold buildup requires extensive cleaning and prep work. Some people think that they can just paint over the mold to hide it and solve the problem. This is never a good idea. Not only can the mold still grow underneath a fresh coat of paint, it can also cause the paint to peel away over time. If anyone in your house suffers from allergies or health problems caused by mold, it is very important that you properly remove the mold before painting. This article explains the best tools and techniques for comprehensive mold removal before painting.
What You Need
Trisodium phosphate (or TSP) is the best product for removing mold from any type of wall, whether it be stucco or drywall. It usually comes in powder form that you just mix with water. There are also many tools you can use for applying the TSP and scrubbing your walls. If you have a pressure washer that has a hopper or reservoir for mixing cleaning liquids as it is being sprayed, this works the best for waterproof surfaces. Obviously, you won't want to use this technique for cleaning interior walls.
Removing the Mold
When cleaning drywall, you don't want to completely soak your walls in water. Instead, you can just mix the TSP in a bucket of water and use a handheld scrub brush. Just be more sparing when it comes to getting your drywall wet. Most mold is actually caused by too much moisture. It is hard to predict how much scrubbing will be necessary. However, you should definitely spray the TSP onto your walls and let it soak in for a bit (an hour or so) to help break down the mold and dirt.
If the mold is not easily washing off, you might need to call in the professionals. However, they will usually use the same cleaning techniques that you already tried. Unfortunately, if the mold can't be clean, this means that the wall my need to be completely changed. This is obviously a very expensive in major remodel.
Another important step in preventing future mold formation is priming your walls before painting them. Wait for your newly cleaned walls to completely dry before applying any paint. Even though some paints claim to have primer mixed in, they do not work as well as a separate primer. Applying two or more coats of primer gives you more protection. Similarly, you can apply multiple coats of paint for a more durable finish. This is particularly helpful in damp, indoor environments with drywall, like in a shower or kitchen.
When it comes to cleaning your walls that show signs of mold, you don't want to skimp. In fact, the actual cleaning might take longer than applying the paint. Contact a company like Artios Painting to learn more.