The Use of Reflective Foil in Steel Buildings
Since World War II reflective insulation has become more and more popular for a variety of applications, most notably in steel buildings. Recently, the use of reflective materials has rapidly gained acceptance in a broad variety of construction applications. Reflective foil works on a very simple principle of being able to reflect radiant energy back from the foil and diffuse it through the building.
The control of heat transfer is the key to temperature management in any building. There is a difference, usually, in temperature inside and outside of a steel building. Heat typically moves from hotter areas to cooler region until the temperature is levelized across a given area. Insulation’s purpose is to impede this process in hot weather, to keep heat from being transferred into the building. Conversely, you want the insulation to stop the transfer of heat out of a steel building in cold weather.
There are three ways in which heat transfer occurs in a steel building. The first is radiation, which is the transfer of heat by infrared radiation across an open field of air space. The second is convection. This is the transfer of heat by the flow of air or by a fluid. This would be seen in a building that is warmed by some form of heating unit and then vented into the structure. The third example is conduction. This involves the transfer of heat between two contacting surfaces. An example of this is a steaming teapot atop a lit gas burner.
When insulating against radiant heat in a steel building remember that fiberglass insulation is an excellent performer in preventing heat transfer by conduction or convection. Fiberglass insulation has almost no effect on radiant heat. Up to 90% of the radiant heat coming in contact with fiberglass insulation will pass through it. Radiant heat transfer has as much impact on the interior temperature of a steel building as does convection or conduction.
The use of aluminum foil in the interior of a steel building can reflect over 95% of radiant energy that strikes it. This is the state-of -the-art for performance driven reflective insulation systems. Reflective foil insulation is composed of two outer layers of foil with an inner layer of material used to create an air gap. When compared to traditional fiberglass insulation reflective foil offers many advantages. Reflective foil is not affected adversely by moisture or humidity. Reflective foil does not lose its performance characteristics when compressed. There is no special clothing needed to install reflective foil and it requires no special handling. Reflective foil does not have any irritants that can affect the eyes, nose, or skin.
Consider the use of reflective foil in your next steel building project. Reflective insulation can make a otherwise uncomfortable interior environment a very pleasant place to work.