What is Foam Board Insulation?
Foam board insulation is a sheet, usually four by eight feet (1.2 by 2.4 m) in size, of rigid foam used in nearly all aspects of building construction to provide thermal resistance in floors, ceilings and walls. Basically, three materials are used to make foam board: polyurethane, polyisocyanurate and polystyrene. Polyurethane and polyisocyanurate foam board are very similar in content. The closed-cell foam board is made by first liquefying the pellets, and then introducing a blowing agent. In the case of these two products, the blowing agent is usually one of the hydro fluoro compounds (HFC) or chloro fluoro carbons (CFC). The blowing agent forms gas bubbles in the mixture when it is heated. The hot, liquefied polyurethane or polyisocyanurate is then forced into a board-shaping dye. After the mixture cools, it is cut into any desired length. The resulting foam board insulation is of higher R (resistance to heat flow) value than a polystyrene foam board, usually R7 or R8 per inch (2.54
A high resistance value recommends the use of foam board insulation in buildings. However, this resistance value can be affected by various factors, like the initial density of the foam board, the way the panels are handled, the type of facing used, the conditions during installation and such. Even so, foam board insulation is preferred against other products for its resistance qualities. How to Install Foam Board Insulation There are several ways for applying foam board insulation. Foam board insulation can be used from aerosol containers and sprayed as a chemical mixture or in bulk from a pressure sprayer. This way, all the cavities and spaces in walls are completely covered and sealed. Foam board insulation can be applied as a liquid that enters all the holes before it expands. Also, foam board insulation comes in the form of solidified plastic foam applied as loose beads into blocks or as rigid panels. Foam board insulation is preferred when air infiltration must be kept under cont
