If you need a thin heat barrier that also damps sound, the Suppressor from Thermo-Tec is for you.
The Suppressor uses a polyethylene film to help absorb and reduce vibrations from large, unsupported panels. The foil backing blocks radiant heat (up to 2000° F) as well as conducted heat (up to 300° F -- not for use on exhaust). The adhesive backing makes installation easy. Just peel and stick! Less than 1/8" thick, so it won't affect the fit of carpeting or interior panels.
This Trunk Kit has been put together to provide comprehensive sound damping for your trunk area. The kit includes 4 small (12" x 12") and 8 large (12" x 24") self-adhesive Suppressor mats for a total of 20 square feet. Great for an additional layer between the roof and headliner, too! Each mat is easy to trim to shape with a sharp scissors or shop knife.