HOME IMPROVEMENT : Covering Up--and Uncovering

In any renovation, some jobs, such as rewiring circuitry, are best left to professionals. There are, however, renovation jobs that can be tackled by homeowners, even if they don’t have much experience.

Painting Primer

Follow these tips for a paint job to be proud of:

Often, washing a wall before painting is more important than applying two coats. A light scrubbing with soap and water removes most problems. For mold and mildew, add about 1 quart of household bleach to 3 quarts of water.

Don’t paint over wet walls. To hold the paint effectively, a wall should be clean, smooth and dry. If the weather is making walls wet inside or out, run an air conditioner or dehumidifier, or just wait for more favorable conditions.

Avoid broiling the fresh paint in direct sunlight, which causes bubbling, cracking and other problems.

Apply two thin coats instead of one thick layer. Even if small blemishes show through a thin first coat, resist the temptation to load on extra paint. A single thick layer is likely to dry unevenly and droop in spots, leaving lap lines and wrinkles.

Which type of paint base is better: oil or latex? Easy cleanup and improved resilience are pluses for latex-base paints. Many consumers and professionals, however, still prefer the oil-base variety for durability. If repainting, the most sensible guideline is to stick to the base type used on the previous coat.

Rescue old plaster with a vinegar bath before painting. On older plaster walls, common problems such as swelling, chalking and crumbling can be corrected by washing the walls with a solution of 1 pint white household vinegar in 1 gallon of water. Repeated washings may be needed before sponging the surface with clean water, drying, priming and painting.

Make decorative moldings pop from flat white walls by adding a coat of gloss or semi-gloss.

Reviving Woodwork

Over the years, wood trim that sets off windows, doors, cabinets and walls can become buried under layers of paint or other sealers. Underneath there may be intricately carved oak, maple and other hardwoods that would be expensive to duplicate today--treasures worth uncovering.

In many older buildings, woodwork was sealed with shellac, which can be removed with its solvent, alcohol. If a finish dissolves rapidly when wiped with a rag dipped in alcohol, the finish is shellac. In this case, spray or wipe on denatured alcohol and wipe with fine steel wool, working on small sections because the alcohol will evaporate quickly.

On intricate wood moldings, doors and windows caked with paint, use a heat gun (it looks like a souped-up hair dryer) to soften the layers. It makes scraping easier and is less hazardous than using toxic paint-removing chemicals or a propane torch.

Most woodwork, however, won’t come completely clean. Inevitably, some paint traces remain in corners and in the wood grain just below the surface. Eradicate these traces by sanding or rubbing with steel wool. Small scrapers, chisels and carving knives will clear the paint remnants from crevices.

Rescuing Wood Floors

A dull-looking wood floor in reasonable repair can often be miraculously revived by simply cleaning with turpentine, then coating with polyurethane. To see what the result will look like, wet a small area of the floor with turpentine.

Seriously ravaged wood floors require sanding. When renting a sander, look for a machine called a lever-action drum sander. While many sanders must be tipped on edge to lift the belt from the floor, the lever-action sander has a tilt-up lever, often called a clutch, that raises the drum only. This feature makes the job easier and reduces lap marks. Watch a pro first, however.

Although some floors can be rescued with a two-step sanding, the typical sequence is three separate passes with the drum sander using coarse, medium, and fine sandpaper, in that order. Deep gouges should be filled before the final pass.

After vacuuming thoroughly, the raw wood should be sealed (stained at this point, if desired), then protected with at least a two-coat finish of varnish or polyurethane, the most popular. It’s easy to roll on, dries overnight in most cases and is available in sheens from high gloss to a low-luster satin. To prevent bubbling, apply the sealer with a fine-napped roller.