NCMI was approached by facility personnel at Norwich University concerning deteriorating EDPM membrane on their rooftop ductwork of the Cabot Science building. This specific job was unique because Norwich wanted to keep the existing Foamglas insulation and add EDPM jacketing.
Finding the Solution
Foamglas is 100% closed-cell glass material that is resistant to water and most other liquids. It is impermeable to liquids and does not require the use of a vapor barrier all while reducing the rise of spreading flames as it is non-combustible. To meet the client’s expectations and keep the existing Foamglas insulation, NCMI proposed some solutions. There were two potential options, one being the demolition of the existing material and jacketing and insulation with 2” poly iso insulation and venture clad, or EDPM rubber. Alternatively, if the existing material was only partially compromised, a thinner insulation option could preserve what was intact, and protect the existing membrane moving forward.
The Final Result
Upon removing the damaged material, NCMI identified that the Foamglas was still perfectly fine, so we proposed pinning ½” poly iso Tuff-R board over the existing membrane and Foamglas to add a base that the new EPDM rubber could adhere to. NCMI recognized the value in keeping the Foamglas insulation and worked around the potential adhesion issue to give Norwich the outcome that they wanted.