01 May 1999
Inspections should be performed by the membrane manufacturer, a professional roofing contractor or
by a qualified individual knowledgeable about the installation and maintenance of PVC roof
membranes. As a result of the inspection, small splits (if found) should be repaired and precautions
taken where items are identified which could puncture or fall onto the roof (e.g., tree limbs), since
these items could initiate shattering.
4. Maintenance and cold weather precautions
According to the survey data, shattering occurs most frequently in cold weather. When the roof
membrane is identified as an unreinforced PVC, rooftop traffic should be avoided when the ambient
temperature is below approximately 10oC (+50 degrees F).*
If any roof traffic is required (e.g., for membrane investigation or inspection, or service of HVAC or
other equipment) at temperatures lower than noted above, on unreinforced PVC membranes, there is
a risk of initiating shattering.
If the building owner elects to have any roofing work (reroofing, repair, maintenance) or any other type
of work done at temperatures lower than noted above, the building owner is assuming some risk that
this activity may initiate shattering.
Because there is no evidence that reinforced or fiber supported PVC
membranes are subject to shattering, cold weather restrictions on
rooftop traffic are similar to other membrane systems.
For recommendations regarding reroofing, maintenance, repair, new penetrations or modifications,
contact the manufacturer, a professional roofing contractor or a qualified individual knowledgeable
about the installation and maintenance of PVC roof membranes.
1. Survey Results, Shattering of unreinforced PVC, July 26, 1990, NRCA.
Note: The survey data have not been verified by third party visual inspection.
Disclaimer: SPRI disclaims any responsibility on behalf of itself, its members, and its agents for any damage to roofing as a
result of inspections or for any other cause. SPRI does not make any recommendations on the usage of industry members'
*SPRI recommends that the individual manufacturer of the product be consulted for a specific recommendation regarding
Reprinted with permission of NRCA and SPRI.