Building insulation materials jagged, shredded, or scuffed). When found in the home, asbestos often resembles grayish-white corrugated cardboard coated with cloth or canvas, usually held in place around pipes and ducts with metal straps. Things that typically might contain asbestos: All polyurethane foams are composed of petrochemicals. Foam insulation often uses hazardous chemicals with high human toxicity, such as isocyanates, benzene and toluene. The foaming agents no longer use ozone-depleting substances. Personal Protective Equipment is required for all people in the area being sprayed to eliminate exposure to isocyanates which constitute about 50% of the foam raw material. Fiberglass is the most common
Cavity wall insulation cavities, a fibrous material such as cellulose insulation or glass wool is blown into the cavity through suitably drilled holes until it fills the entire wall space. Foam can also be used for this purpose. Although some foams used in the past, such as urea-formaldehyde, are no longer used (some people are allergic to this material, which is very difficult to remove once inside the wall), others, such as polyurethane, have taken their place. Cavity wall insulation also helps to prevent convection and can keep a house warm by making sure that less heat is lost through walls; this can