Painting with Elastomeric Paint
One of the very best exterior finishes around is elastomeric paint; it is outstanding in the durability category, and can outperform even the very best exterior acrylic paint by 2 to 1. Elastomeric is not your typical paint, however it forms a very tough film which provides a snug, waterproof coating to virtually any structure and is much more resistant to sunlight, heat, cold and rain than any regular paint. Elastomeric can also be applied to any masonry surfaces such as stucco and concrete or cinderblock. Elastomeric can be used for wood or wood siding, just check the label of the type you choose to make sure it is compatible.
If you have masonry, or wood exteriors which have a substantial amount of cracks, a thick coat of elastomeric can nearly eliminate these cracks. Oftentimes stucco develops numerous cracks over the years, but imperfections can be almost completely filled with elastomeric. Elastomeric coatings are designed to stretch and flex when temperatures drop, and contract to their original shape when temperatures return to normal without warping or wrinkling. While elastomeric is waterproof, it still allows the exterior surface to "breathe," thus allowing moisture form within the home to escape outdoors as a vapor.
Just as with any paint, you need to thoroughly prep the surface prior to painting. Good surface preparation is critical for adhesion; the elastomeric product is much thicker and heavier than typical paint, so must have excellent adhesion. Seal any cracks larger than 1/16" with a silicon caulk prior to applying your elastomeric top coat. If you are painting the elastomeric over a porous or chalky surface, you may need to apply a sealer first-elastomeric paints do have superior alkali resistance, however a sealer can just give you that added level of protection for your home. Check the various brands of elastomeric paint, and make sure you are using a high-quality brand with an 100-percent acrylic binder. Apply your elastomeric according to recommendations in order to achieve the maximum flexibility. Generally you will apply two very thick coats. If you apply two coats of elastomeric paint over an exceptionally high-quality primer, you will achieve a totally waterproof surface. Elastomeric paint will often last over twelve years while maintaining their beauty.
Cost of Elastomeric
Be prepared to pay at least 50% more for elastomeric than for standard exterior house paint. Expect to get about 50-75 square feet per gallon, and figure accordingly. If you are intending to pay for labor to apply the elastomeric, you will also pay more-and you should pay more to get a painter who is highly experienced in applying elastomeric.
You can use a brush and roller, or an airless paint sprayer to apply the elastomeric. It is advisable to use an airless paint sprayer, as it can be very hard to achieve the proper thickness with a roller and brush. The only time rolling is advocated, is when you are putting elastomeric onto a rough surface. You can also use a technique known as back rolling, which means spraying on the elastomeric, then having a second person following behind with a roller to fill in small cracks and even out any uneven spots. If you choose to use an airless paint sprayer, you will need to rent a very large, heavy-duty sprayer with at least one gallon per minute output and a tip size of 521 or larger. You can thin Elastomeric a bit with water, but remember to clean up quickly with mild soap and water following application, as elastomeric can be difficult to remove from skin.
Types of Elastomeric
You can buy elastomeric in every sheen from flat to gloss, although you will use satin for most applications; it will give you a nice durable finish that won't be too shiny. You can find elastomeric in large home improvement stores such as Home Depot or Lowes. You can get elastomeric in smooth and textured surfaces, and it's a good idea to discuss your needs with a paint professional at the home improvement store.