QThe exterior stucco on our home is dingy and discolored. We would like to refresh it with a coat of paint. What type of preparation is required and what type of paint would you suggest?
AOften the recommendation is that you shouldn't paint stucco if you don't have to. Once it's painted, you will have to repaint periodically.
Climate is another factor. In warmer climates where the temperature does not drop below freezing, paint coatings are more durable. In colder climes, moisture seeping through walls that have no vapor barriers can cause problems with paint during the freeze-thaw cycles.
However, with new technology and the development of new product lines, you have a couple of options to consider.
The most durable refinishing for stucco is a cement-base stucco coating, which is the recommended choice for colder climates. These are available in dry form and must be mixed with water.
Mix the stucco according to directions and apply it over the old stucco using a rental hopper-style sprayer or a sponge, brush or roller. There are several different manufacturers of stucco resurfacing products that come in a wide choice of colors. Professional resurfacing is also available in most areas.
If you use a professional, get several bids and read all the warranties carefully. Some firms will guarantee their work up to 20 years.
If you live in a moderate climate, not subject to the freeze-thaw cycle, you can consider the use of paint on stucco. United Gilsonite Laboratories has recently introduced a new product, Drylok Masonry & Stucco Paint, specially formulated for vertical masonry surfaces. It can be applied to freshly applied stucco, adobe and concrete. It can also be applied to previously finished masonry or stucco surfaces. It's an acrylic-based paint that goes on and cleans up like standard latex. The acrylic adheres better than other paints, and it stands up better to ultraviolet light, which prevents fading. But most important, acrylic helps the paint remain flexible, so it won't crack when the stucco contracts and expands with cold and heat.
No matter which resurfacing method you choose, the existing surface must be cleaned thoroughly to remove all loose material, including peeling paint, dirt and efflorescence (white powdery deposits that sometimes form on masonry). Muriatic acid is often used to rid the surface of efflorescence. Brushing with a stiff brush might be adequate for surface preparation, but power washing (equipment can be rented) or sometimes even sandblasting may be necessary.
After cleaning, rinse the surface thoroughly with clear water and let dry. A new stucco coating will be more durable than paint. Painting will be less expensive, although repainting will be required periodically.
If you choose to paint, use a paint roller with a denser, longer nap, which is best for application on the rough stucco texture. Two coats are recommended.
We purchased an older house that has badly damaged plastered walls. Is there any way to resurface these walls without completely patching and replastering?
There is a fiberglass covering, Nu-Wal Restoration System, which is designed as an efficient system for repairing damaged plaster substrates of walls and ceiling. The non-woven fiberglass mat, used with an acrylic binder, creates a surface that resists impacts and abrasions. Cracks in exterior or interior surfaces do not come back as they do with patching compounds.
Application methods are similar to hanging wallpaper. The restored surface is ideal for either painting or wallpapering, and it is much less expensive than reconstruction. The fiberglass mat is embedded with a special coating and then covered with an acrylic topcoat that provides a waterproof, tough and flexible finish coat. The wall surface must be free of oil, dirt, dust, mildew or other contaminants, and all loose particles must be removed. If the plaster has shifted as a result of a crack, it must be sanded to an even plane.
It is not necessary to fill cracks that are one-sixteenth of an inch wide or less, as the coating will fill and adhere the plaster. Larger cracks at inside corners may be filled with the one or two coats of the embedding compound. Large holes may require repair with patching plaster or drywall compound.
All bare plaster and patched areas must be primed. If walls and ceiling are chalky, they must be sealed with a penetrating surface conditioner. Gloss enamel on surfaces should be sanded with fine sandpaper or sealed with a primer.
For information, contact Specification Chemicals Inc., 824 Keeler St., Boone, Iowa, 50036; phone 800-247-3932; Web www.spec-chem.com.
Send e-mail to firstname.lastname@example.org or write to Here's How, Copley News Service, P.O. Box 120190, San Diego, Calif. 92112-0190.