Painting the whole outside of your house is a major job. But your home may not need a whole paint job. You may be able to spiff up the appearance of your home and extend the life of an entire paint job by several years with regular maintenance and some quick repairs. Whether you decide to paint a porch, the most weathered side of your house, or an outbuilding or two, the general process is the same as painting your whole house.You’ll need to clean and prep the surface, decide what type of paint to use, and apply the paint. The best time to paint is in late spring or early fall on a dry day that is not too sunny. Temperatures below 40 degrees F and direct hot sun can ruin paint jobs. Inspect your house thoroughly before you paint, and take corrective action to prevent the root causes of paint failure.
We’ll hit on all the basics of exterior painting in his article, starting in this first section with how to deal with various paint problems.PeelingPeeling is often the result of painting over wet wood. It can also result from moisture within the house pushing its way out. If you cannot control the moisture with exhaust fans, use latex primer and latex paint. Latex allows some moisture to pass right through the paint.Another cause of peeling is a dirty or a glossy surface. To undo the damage, all loose paint flakes must be scraped off with a wire brush and the surface must be sanded to smooth sharp edges. Bare spots should be primed before painting.AlligatoringThis problem looks just like its name suggests: the hide of an alligator. Paint shrinks into individual islands, exposing the previous surface, usually because the top coat is not adhering to the paint below. Perhaps the paints are not compatible or the second coat was applied before the first coat had dried. To get rid of this problem, scrape off the old paint and then sand, prime, and repaint the surface.BlisteringPaint that rises from the surface and forms blisters is usually due to moisture or improper painting. To fix the problem, first scrape off the blisters. If you can see dry wood behind them, the problem is due to moisture. If you find paint, then it is a solvent blister and is probably caused by painting with an oilbase or alkyd-base coating in hot weather. The heat forms a skin on the paint and traps solvent in a bubble.WrinklingNew paint can run and sag into a series of slack, skinlike droops. This occurs when the paint you are using is too thick and forms a surface film over the still-liquid paint below. It can also happen if you paint in cold weather; the cold surface slows drying underneath. To recoat, make sure the new paint is the proper consistency and be sure to brush it out as you apply. Before doing this, though, you will have to sand the wrinkled area smooth and, if necessary, remove the paint altogether.ChalkingThis is paint that has a dusty surface. Some oilbase and alkyd-base paints are designed to “chalk” when it rains. When this happens, a very fine powdery layer is removed, automatically cleaning the surface. In most cases, this is desirable. But if foundations, sidewalks, and shrubs become stained, too much chalking is occurring.This is likely due to painting over a too-porous surface that has absorbed too much of the paint’s binding agents. A chemical imbalance in an inferior paint may also be the cause of excessive chalking. The best solution is to wash down the chalking surfaces as thoroughly as possible, then paint over them with a nonchalking paint.MildewThis moldy growth appears where dampness and shade prevail. And, if you paint over it, it’s likely to come right through the new paint. Use a fungicide such as chlorine bleach or a commercial solution to kill patches of mildew before repainting.Running SagsUsing a paintbrush incorrectly (e.g., too much paint on the brush) can create a wavy, irregular surface. To correct it after the paint is dry, sand and repaint surface, smoothing out the new coat to an even thickness.Paint Won’t DryThis is perhaps the best reason to buy high-quality paint. Prolonged tackiness is an indication of inferior paint. If you apply poor-quality paint too thickly or during high humidity, it will stay tacky for a long time. Good paint, on the other hand, dries quickly. If you think you may have an inferior paint, first experiment on an inconspicuous portion of the house.Think you’re ready to get started? In the next section, we’ll go over the prep work you’ll need to do before you begin your outdoor painting project.
How to Prep for Painting a House
If you’re lucky, all your house may need before repainting is a good, healthy bath. Wash it down with a hose, and go over stubborn dirt with a scrub brush and warm, soapy water. Or wash it down with a power washer. If you’re not so lucky, then you just have to face the fact that a time-consuming and dirty job lies ahead of you. Do the job well, and your paint job will not only look better, but it will last for five to eight years on average.Start by thoroughly examining the outside of the house or outbuilding — not just the exterior walls but under the eaves, around windows and doors, and along the foundation. Look for split shingles and siding, popped nails, peeling or blistering paint, mildew, and rust stains. Once you’ve identified the areas that need attention, roll up your sleeves and make the repairs.
©2006 Publications International, Ltd.
Remove small areas of defective paint with a wire brush and/or a
wide-blade putty knife. Scrub under the laps of clapboard siding
and on downspouts and gutters.
ScrapingUse a wire brush and a wide-blade putty knife to remove small areas of defective paint. Scrub under the laps of clapboard siding as well as on downspouts and gutters. For speedier work on metal, a wire brush attachment on an electric drill will remove rust and paint with less effort. For more extensive paint removal, invest in a sharp pull scraper — a tool with a replaceable blade that’s capable of stripping old paint all the way down to bare wood with a single scrape. Hold the scraper so the blade is perpendicular to the wood, apply moderate to firm pressure, and drag it along the surface. Keep the blade flat against the wood so it doesn’t gouge the surface.
©2006 Publications International, Ltd.
Move an electric orbital sander up and down or back and forth to
remove old paint and feather rough edges.
SandingFor smoothing the edges of scraped spots here and there, you can wrap a piece of sandpaper around a wood block. For larger areas, it’s less tiring and more effective to use an electric orbital sander. Move it up and down or back and forth across the surface to remove old paint and smooth rough edges at the same time. Don’t use an electric disc sander or a belt sander. Both can leave swirls or dips in the wood that will show through a new coat of paint.