Low-E Radiant Barrier Under Roof

Ask The Expert – Q & ACategory: Low-ELow-E Radiant Barrier Under Roof
RIMA Expert Staff asked 3 years ago

I am considering using a product call Low-E Therma-Sheet under a composite shingle roof to be installed in a few weeks. It is installed directly under the shingles with no air space.

I’m very concerned about the claims made about this product and wonder if your organization has any reports or reservations about this product – especially used in the manner I just described.

1 Answers
Best Answer
RIMA Expert Staff answered 3 years ago

Reflective insulation and radiant barriers must be installed in such a manner that their reflective surface(s) face an air space. Reflection of heat does not occur unless this condition is met. When a reflective material is in contact with another surface it becomes a direct conductor of heat at all points of contact. Installing it under shingles will not provide you with any worthwhile performance.