thermoset Thermoset Membranes Thermoset Membranes thermoset

Material and system description

Thermoset membranes incorporate   principal polymers that are chemically cross linked or vulcanized. Membranes   that are vulcanized also may be referred to as “cured.” One characteristic of   true thermoset polymers is once they are cured, they only can be bonded to   similar materials with adhesives.

There are five common subcategories of   thermoset roof membranes:

  • Ethylene propylene diene terpolymer (EPDM)
  • Chlorosulfonated polyethylene (CSPE)
  • Epichlorohydrin (ECH)
  • Neoprene (CR)
  • Polyisobutylene (PIB)

The most common thermoset roof membrane is   EPDM. EPDM principally is composed of two compounds, ethylene and propylene,   that are derived from oil and natural gas. The following are some   characteristics of EPDM roof membranes:

  • Sheet widths range from 7.5 feet to 50 feet wide.
  • Sheets are typically 45 mils and 60 mils thick.
  • Seams are sealed using liquid adhesives or special formulated tape.
  • The membranes commonly are black, but white is available.

EPDM   roof membranes can be installed fully adhered, mechanically attached (using   batten bars) or ballasted. Most EPDM membranes do not receive surfacings.

EPDM and polymer-modified bitumen   membranes often are confused by consumers because of colloquialisms used by   roofing contractors. Contractors commonly call both of these membranes “rubber”   roofs. However, in most cases, when contractors specify rubber roofs, they are   referring to EPDM.