Stucco is a mortar mixture used for siding. It can be made by mixing sand and lime with water and various other ingredients, most often cement. Usually, wooden walls are covered with tar paper and chicken wire or galvanized metal screening. This framework is then covered with the stucco mixture. Sometimes, the mixture is applied directly to specially prepared masonry surfaces.
Although stucco-sided homes became popular in twentieth century America, the concept of using stucco mixtures in architecture goes back to ancient times. Wall frescoes by ancient Greeks and Romans were painted on fine-grained hard plaster surfaces made of gypsum, marble dust, and glue.
Many homes built after the 1950s use a variety of synthetic materials that resemble stucco. Mock stucco siding is often composed of foam insulation board or cement panels secured to the walls. Although synthetic stucco may look authentic, real stucco tends to be heavier. Walls made of genuine stucco sound solid when tapped and will be less likely to suffer damage from a hard blow. Also, genuine stucco holds up well in wet conditions. Although it is porous and will absorb moisture, genuine stucco will dry easily, without damage to the structure.
One type of synthetic stucco, known as EIFS (Exterior Insulation and Finish Systems), has been associated with moisture problems. The underlying wood on EIFS sided homes may suffer rot damage. However, other types of synthetic stucco are quite durable. Most realtors will tell you it’s always wise to have a professional stucco inspection before purchasing a stucco-sided home.