Insulation
An added benefit of cavity wall construction is that it provides the ability to more adequately insulate the building. A continuous layer of rigid insulation is easily fitted between the cavity and the inner skin of the wall. The insulation does not fill the cavity but rather slip in behind it. The cavity itself also helps in insulating the building by acting as a thermal break between the two skins of the wall.
With environmental conditions becoming more of an issue,people now take much more interest in reducing energy wastage and cavity wall insulation is a cost effective way to reduce the amount of heat (as much as 35%) lost from convection off walls. As well as being more environmentally friendly, it can reduce heating costs as more of the heat is used effectively and it is often used as a first step, due to its low payback time and smaller initial installation costs. As the demand for energy efficiency in buildings increases the issue of thermal bridging in cavity wall openings is becoming more prominent. Solutions to thermal bridging include cavity closers, an insulated frame seals the cavity at apertures for doors and windows.
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