Building insulation materials is used depends on a wide variety of factors. Some insulation materials have health risks, some so significant the materials are no longer allowed to be used but remain in use in some older buildings such as asbestos fibers and urea. Factors affecting the type and amount of insulation to use in a building include: Considerations regarding building and climate: Often a combination of materials is used to achieve an optimum solution and there are products which combine different types of insulation into a single form. Spray foam is a type of insulation that is sprayed in place through a
Building insulation materials hour fire rating according to DIN (German) standards. An additional source of insulation derived from hemp is hempcrete, which consists of hemp hurds (shives) mixed with a lime binder. It has little structural strength but can provide racking strength and insulation with comparable or superior R-values depending on the ratio of hemp to binder. Sheep's wool insulation is a very efficient thermal insulator with a higher performance than glass fibre and no reduction in performance even when condensation is present. It is made from the waste wool that the carpet and textile industries reject, it is available in both rolls