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Here's how to do the prep work on three of worst painting trouble spots. Prepping them right can double the life of your paint job.
Wood Close to the Ground
If the lower ends of your garage door trim just won’t hold paint, here’s why: Concrete soaks up water, then releases moisture slowly. So any wood next to ground-level concrete stays damp, and that constant dampness breaks the wood/paint bond. The same goes for any wood that touches a deck, patio or other surface where water sits.
To correct the problem, create a gap between wood and horizontal surfaces. Then apply paintable water repellent to the bottom 16 in. of the wood. Properly applied repellents add several years to a paint job in areas highly vulnerable to moisture. (See Buyer’s Guide for sources.)
Begin by scraping away all the paint in the peeling area. Two or three coats of paint can usually be removed with a combination of paint scrapers and sandpaper. For heavier buildup, use a heat gun to soften the paint as you scrape. Be careful with a heat gun—it can melt nearby vinyl and weatherstripping. As you scrape, you may find that the wood has turned gray or black in some areas. Check for rot by probing these areas with a nail. Spots that are discolored but firm are simply weathered. Weathered wood doesn’t hold paint very well, so sand away the gray surface. If you find soft areas, you’ve got rot. Small, shallow soft spots can be dug out and repaired with a two-part filler such as Minwax High Performance Wood Filler (800-523-9299). But when rot is deep and widespread, it’s best to replace the entire piece of wood.
Next, undercut the trim to create a gap. When you’re done, scrape any dirt or gunk out of the gap with a putty knife and blow out the dust using a vacuum or air compressor. To avoid staining the concrete, run at least three layers of masking tape under the wood. Apply repellent to all bare wood including the underside. Bend a putty knife in a vise to make a handy tool for reaching into tight areas. Remove the tape right after application.
The label on the repellent will tell you how long to wait before applying a primer. Many repellents require an oil-based primer, so be sure to read the label. Then apply two coats of paint. A single coat of paint may look fine, but two coats form a more durable film that resists moisture better and lasts longer. When using paint and primer, don’t ignore the temperature and humidity ranges listed on the label—weather conditions during application really do affect paint longevity.
CAUTION: If your home was built before 1979, the paint might contain lead, which is extremely hazardous to children age 6 and younger. Call your local public health department for information on how to check for lead and handle lead paint safely. For a free booklet on dealing with lead paint, contact the U.S. Environmental Protection Agency: (800) 424-5323; www.epa.gov/lead.
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