Artificial Stone Veneer
DEAR TIM: I am in the planning stages of an upcoming building project that requires stone work. After obtaining quotations for this work, I am over budget. A friend suggested that I look into the artificial stone products. After visiting a local supplier of these products I was amazed. The samples looked like real stone. What can you tell me about these products? Are they affordable? Would you install it on one of your projects? N. I.
DEAR N. I.: Have you had your vision checked lately? Just kidding! I couldn't agree more with you. Artificial stone products are extremely realistic. In fact, I was a geology major in college and many of these products look exactly like the rocks that I used to study and crack with my rock hammer. I am very impressed with these materials.
Many artificial stone products are both lightweight and durable. These two qualities are achieved by manufacturing the stones in a controlled environment. Just about every artificial stone is made by mixing small, lightweight pieces of aggregate, Portland cement, and different iron oxide pigments. This mixture is poured into hundreds of different flexible molds which vibrate. This vibratory motion is the key to producing realistic textures and color variations in each individual stone. Because these stones are very similar to concrete and are manufactured under controlled conditions, they will probably outlast both you and I combined.
The fact that these products are lightweight gives them a unique advantage over natural stone products. Artificial stone products do not require foundations beneath them for support. They are attached to buildings in a manner very similar to applying stucco. If your house is wood framed, a wire lath is applied directly to the wood studs or over the exterior wall sheathing after a weather resistant barrier has been applied. This barrier can be either standard asphalt felt paper or one of the many waterproof air infiltration barriers. Once the metal lath has been securely fastened to the wall framing members, the installer simply applies a one-half to three-quarters inch thick layer of mortar onto the lath. The stones are set directly into this fresh mortar. Many manufactures recommend using specific colored mortars depending upon the color of the stone being used.
If your structure is masonry to begin with, you simply apply the coat of mortar directly onto the concrete block, brick, or poured concrete. It is a fairly simple procedure.
Anyway, there is no limit as to where these products can be used. You can use them for any exterior wall surface, free standing exterior perimeter or garden walls, coverings for exterior metal or masonry chimneys, interior fireplace fronts, columns, wainscoting, etc. You can even do the interior of your office if you desire to simulate a room in a castle. Some manufactures even make artificial cobblestones for driveways and walkways. Artificial brick is available as well.
Some people in the past have expressed concerns about the color fastness of artificial stone products. For the record, many people don't realize that natural stone will both fade and discolor as a result of oxidation and exposure to weather. The artificial stone products are manufactured in such a way that the color is integral throughout each piece. Some manufacturers have developed an additional process which imparts shade variations directly from the face of the molds. This makes the stone products virtually indistinguishable from their natural stone counterparts.
Artificial stone products should also help you with your budget problem. Frequently the cost of a complete installation is 50 - 60 percent that of a similar natural stone installation. The current retail cost of many of the artificial stone products is about $4 per square foot. Labor, mortar, and other costs may add an additional $4 - 8 per square foot depending upon your locality. (Prices shown are from the time the article was written in 1995.)
I wouldn't hesitate to use the artificial stone products on one of my projects. In fact, I wish that I would have used it to face the foundation of my existing house. I built a country Victorian house 9-years-ago and the exposed parts of my foundation would have looked magnificent had I used one of these products. Oh well, I'll do it right on my next house!