You may find that vapour barriers are often not required in warmer climates. And, if installed in the wrong climate or on the wrong side of building materials, a vapour barrier can cause more harm than good. This circumstance may prevent water vapour from drying, which in turn can cause rot and mold. (Source: Dupont.)

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.

In the context of construction, the R-value is a measure of how well a two-dimensional barrier, such as a layer of insulation, a window or a complete wall or ceiling, resists the conductive flow of heat.

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.