Radiant Barrier Moisture Problems The other main issue that can impact the performance of any radiant barrier is moisture. In colder weather, radiant barriers can sometimes develop condensation. This issue is most prevalent in climates where the temperature regularly falls below zero degrees Fahrenheit.

Some studies show that radiant barriers can reduce cooling costs 5% to 10% when used in a warm, sunny climate. The reduced heat gain may even allow for a smaller air conditioning system. In cool climates, however, it's usually more cost-effective to install more thermal insulation than to add a radiant barrier.

Mold growth and the corrosion of metal surfaces are common problems that can result from excess moisture in the home. And moisture can also cause wood rot and infestations of pests such as termites.

Unfaced insulation works the same way as faced insulation in terms of insulating the home. But unlike its faced counterpart, unfaced insulation doesn't have a vapor barrier, making it susceptible to external elements such as rain, moisture, or the sun's extreme heat.