- 1). Clean your drywall thoroughly before applying any paints and sealants. Any dirt left behind will become permanently sealed on the wall surface if you fail to eliminate it. Sponge the wall with mild liquid detergent and water, and allow the wall to dry completely.
- 2). Paint over your drywall and trim with one to two coats of primer, using smooth, even brush strokes to cover the entire surface. Primer offers effective mildew protection because it seals moisture out of porous materials much better than paint alone. Allow the primer to dry completely before proceeding to the next step.
- 3). Sand your wall and trim gently to smooth out the primer. Walls can accumulate dust and dirt during and after priming, and the primer itself can dry unevenly, leaving the wall with a rocky appearance in certain areas. Simply brush over the wall surface using a block sander, but do not press the sander against the wall with excess force, as that may scratch the drywall.
- 4). Paint over your drywall and trim liberally with a mildew resistant paint. Never cover drywall with wallpaper, because it contains cellulose that mold can feed on, and thereby elevates your mildew and mold risk. You can find mildew resistant paints at paint supply stores, as well as at home home supply stores. The label should contain the words “mildew resistant,” “mold resistant” or “mildewcide” in plain sight. Do not use the same color paint for your drywall and trim, as the trim looks best when it provides contrast to the drywall.
- 5). Provide your home with plenty of warmth and adequate air circulation long after the paint dries. Even if you provide your home with optimal mildew and mold resistance, these organisms can still grow if you live in poor conditions. Buy a dehumidifier if you live in an extremely humid area, or open windows during the day to promote a healthy flow of air.
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