A project architect asked me to put together a brief overview of advantages and disadvantages of the different single ply roofing systems (EPDM, PVC, TPO, etc.)
Does anybody know where I can find factural information without advertising or product rep spin?
Try the NRCA Low-Slope Roofing Guide, which summarizes the systems available from the various manufacturers. It won’t give you everything you need, but it is a start.
I don’t think the NRCA has published its most recent national survey on the performance of low-slope roofing systems. Seems some of the results aren’t so good …
There are a couple of articles in the Construction Specifier archive that might help.
I think it would be advantageous for the architectural firm to have a roofing consultant who could review drawings and specifications and provide this sort of advice. I’ve seen roofing consultants who have brutalized a set of drawings and saved the architect the greater disaster of construction change orders or, worse, roofing failutes.
A roofing consultant should be able to provide the synopses you are looking for.
Also, it might be comforting to know that your firm has already engaged the best roofing consultant so that if there is a problem you won’t be on the opposite side of the table from him/her trying to resolve a claim.
AECDaily.com has a decent Powerpoint training module at AEC Daily Learning Center - Browse by Latest Releases (registration is required).
It has a lot of detail behind the slides you can explore, and you can “Save As” to your drive. (also, if you register on the AECDaily Online Learning Center site and take an easy test you can even get CE credits).
When specifying a PVC single ply roof in the past, I have tried to use the thickest membrane available, 80, 96, or 100 mils for example. In trying to adapt Section 07540 from MASTERSPEC, I have found that the standard offerings are 48 and 60 mils. Sarnafils manufacturers literature offers the option of other membrane thicknesses, but they do not go into actual numbers. There is an option to write in an alternate thickness. Is this realistic? Other manufacturers seem to offer membranes with different, but similar, standard thicknesses. Given the nature of the manufacturing and marketing processes, is specifying an alternative to the standard PVC thicknesses a realistic or practical position?
My reasoning for selecting the thicker PVC membranes is that they provide a more durable system. Most membranes are reinforced, so tear resistance is probably not any better. A thicker membrane may be more puncture resistant. It might be more durable to exterior exposure. On the other hand, a thicker membrane may not have as much give during the temperature swings to which roofs are subjected. Does specifying a thicker PVC roof membrane really provide a better roof?
Bigger is not always better. Is a coconut better than a diamond? Thicker PVC single ply may just mean there’s more fillers, which is not an advantage. Check with the manufacturers for the exact composition of their materials.
Why is roof design always a default to product & 1st cost?
What about function & occupancy of the structure, climate, code compliance, expected life cycle & LFC, repairability, contractor expertise, etc.
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