One of the common arguments against radiant barrier is that it is a product best suited for warm weather climates and provides little benefits for those that live in cold climates. As we have shown, radiant barrier works very well in warm climates, but radiant barrier can also provide cost and energy-saving benefits to those that live in cold climates.
Essentially, radiant barrier works the same if you live in a cold or warm weather climate, but serves a little bit different purpose in each. To understand how radiant barrier works in cold weather climates, you first need to understand the three different types of heat escaping from your home. The three modes of heat transfer are: conduction, convection, and radiation.
Radiant heat transfer is the most dominant mode of heat transfer, even in cold climates. Radiant heat transfer is the transmission of electromagnetic rays through space.
In the winter, 50 to 70% of the heat escaping through the ceiling and roof is radiant heat.
This is where radiant barrier can provide huge comfort and energy saving benefits. It can be installed in a household attic using a variety of methods, but the most common are to staple it up to the rafters or lay it down over the existing insulation on the attic floor. For our customers in cold weather climates, best results can be achieved be installing their radiant barrier on the floor of the attic.
The radiant barrier, laying on the floor of the attic, will reflect 95% of the radiant heat that is lost through the ceiling back into the home.
According to a study conducted by the Tennessee Valley Authority, radiant barrier can provide a 17% average reduction in heat flow throughout the winter, indicating that the radiant barrier was keeping a significant amount of heat from escaping. A separate climate study conducted by the University of Kansas found there are a variety of different factors in every climate that impact the energy efficiency of a home, but regardless of climate, radiant barrier saves energy and improves the level of comfort.
Another factor to consider when talking about homes in cold climates is moisture. When extreme temperature differences occur between the inside and outside of a home, condensation naturally occurs. This can be a huge problem with insulation products, which absorb moisture, greatly decreasing the R value (insulation value). On the other hand, the performance of radiant barrier is unaffected by moisture. Some insulation products have a vapor barrier attached, like kraft paper or foil. Installed incorrectly, these can even lead to mold or mildew. However, well perforated radiant barrier, installed correctly, will allow water vapor to easily escape.
By reflecting the heat back into your home before it has a chance to escape into your attic and out through your roof, a radiant barrier has the potential to keep you warm and cozy in your home no matter how cold it is outside.