Single Ply Membranes are becoming increasingly popular but represent perhaps the least understood type of water-proofing for flat roofs in our market. This is not to be confused with the fact that single-ply technology has existed for over forty years and has been very commonly used in various European markets such as Britain, Germany, and the Netherlands.
Single-ply membranes are divided into three basic types:
- TPO (Thermo-plastic polyolefin)
- EPDM (Ethylene-propylene diene-monomer)
- PVC (Poly-vinyl Chloride)
Such membranes are commonly 45 and 60-mil membrane sheets with other thicknesses available.
All of these single-ply assemblies share some basic similarities in terms of installation methodology. All can be loose-laid or fully adhered. All can be used in a PMR roof assembly (protected, membrane roof assembly-where thermal insulation is applied externally to the waterproofing membrane, and ballasted with a filter cloth layer and pavers, or heavy river-washed stone acting as the ballast).
All single-ply systems can be installed using a liquid adhesive; with EPDM also having the opportunity to be applied using hot asphalt in a certain configuration(felt backed EPDM).
The differences in single-ply systems, aside from different chemical structures between each other, are often compared against conventional petroleum based asphalt assemblies. They offer great elastomeric qualities, are lighter, and have high tensile strength.
TPO and PVC membranes are known for their light reflective surfaces and qualify as “cool roof assemblies”. Cool roofs are favoured by the City of Toronto as they act to help mitigate “the urban heat island effect”. Cool roofs in combination with thermal insulation are proven to reduce heating and cooling costs and do not off-gas as asphalt based products do.
With such membranes being fully recyclable; they are a preferred choice in many North American cities such as New York, Chicago, and Philadelphia.
Consult with the Commercial Division of ARR® to evaluate what the best choices are for your commercial, industrial, or institutional building. Competent design and installation by experts who care about supplying a quality result.
