White EPDM

Log Out | Topics | Search Moderators | Register | Edit Profile

Author Message Dewayne Dean Senior Member Username: ddean Post Number: 207 Registered: 02-2016 Posted on Thursday, November 07, 2019 - 08:03 pm:    We have a client insisting on a white EPDM thinking it will be easier to maintain . We are looking for data showing maintenance costs of EPDM vs PVC or TPO. Any help will be appreciated. Lynn Javoroski FCSI CCS LEED® AP SCIP Affiliate Senior Member Username: lynn_javoroski Post Number: 2215 Registered: 07-2002 Posted on Thursday, November 07, 2019 - 09:11 pm:    With any white roof, I tried to make sure facilities were aware of the necessity of keeping it clean. I was told years ago that they should buy Dawn by the case. A dirty white rook isn't much good for the reasons you want a white roof. Make sure there are hose bibs on the roof, too, for the cleaning. And, if there's a problem with the water going into the roof drains, some other arrangement will have to be made. (municipalities that don't allow "grey" water in the rain drain) William C. Pegues Senior Member Username: wpegues Post Number: 985 Registered: 10-2002 Posted on Thursday, November 07, 2019 - 10:36 pm:    There are also several colors of PVC that are not only easy to maintain but also qualify for the reflectivity required by LEED, so it does not have to be white to get the same reflectivity quality. Also, its not white so you are not looking at a glaring white roof if its going to end up as foreground architecture for a higher building, or higher parts of this building. And interesting point that was discovered during research into why solar panels are much less efficient on white roofs is that they reflect the heat back up. So, what has to be considered is that this reflectivity is also reheating everything above it - like if it reflects onto the side of the building, or that its just putting more heat back into the atmosphere. Not that this might not directly impact this particular project, but, white roofs are turning out to be particularly unfriendly. Oh - the other colors of PVC that meet LEED requirements are gray, green, tan, and I think a blue, not sure on the blue. William C. Pegues, FCSI, CCS, SCIP Marc Chavez Senior Member Username: mchavez Post Number: 540 Registered: 07-2002 Posted on Friday, November 08, 2019 - 09:19 am:    contact Carlisle. they have both types available. However, they have done lots of work on why white is not necessarily what you need for every location. they could have some good info ken hercenberg Senior Member Username: khercenberg Post Number: 1254 Registered: 12-2006 Posted on Friday, November 08, 2019 - 09:32 am:    Lots of good suggestions here. I think it's laudable that they care about this. Still, at the risk of stating the obvious, aren't they at least as concerned about which roof performs best, last longest, requires fewest repairs/replacement, tastes great, less filling, etc.? No matter what type of roof they use they'll still have to clean the drains every few months. Is it a given that they already do that? Are they designing in lots of walkway pads or double layers of roof at high traffic patterns if they're planning on having people up there maintaining the roof? John Bunzick, CCS, CCCA, LEED AP Senior Member Username: bunzick Post Number: 1796 Registered: 03-2002 Posted on Friday, November 08, 2019 - 10:56 am:    At one time, at least, white EPDM was known to have a shorter life than black; it is the carbon black that blocks UV and protects the EPDM itself. There are other roof membranes that do not have this shortcoming and have a high reflectance (assuming that a cool roof is what they are looking for). But, as anyone who has eaten spaghetti while wearing a white shirt knows, lighter colors show soiling. Guest (Unregistered Guest) Unregistered guest Posted on Friday, November 08, 2019 - 11:21 am:    It sounds to me like the question isn't whether to go with white membrane or another color as most responses are addressing, but whether one type of white membrane is easier to maintain. Is it also safe to assume that in this case 'maintain' means keep clean and white? I've seen information from Carlisle that their KEE-modified PVC membrane stays cleaner and whiter than their standard PVC membranes. Not sure how that compares to TPO or EPDM though. David J. Wyatt, CDT Senior Member Username: david_j_wyatt_cdt Post Number: 315 Registered: 03-2011 Posted on Friday, November 08, 2019 - 02:09 pm:    What John Bunzick wrote is still correct regarding the durability of white EPDM. Another consideration is that white EPDM is actually a white EPDM sheet laminated to a black EPDM sheet, so it is not a homogeneous membrane. In my part of the country (northern Ohio), when for reasons unknown I am asked to specify a light-colored membrane, I recommend PVC. TPO usually wins when a CM at risk is running the show, however. Dewayne Dean Senior Member Username: ddean Post Number: 208 Registered: 02-2016 Posted on Monday, November 11, 2019 - 09:54 am:    Thanks for the responses. I didn't word the original post very well. The owner is a school district. Their maintenance chief has convinced them that EPDM will be easier for his crews to repair since the EPDM can be glued as opposed to the heat welding that is needed for TPO and PVC. Ease of cleaning is not part of the consideraton. Greta Eckhardt Senior Member Username: gretaeckhardt Post Number: 113 Registered: 08-2013 Posted on Monday, November 11, 2019 - 11:14 am:    As David Wyatt mentions, the white EPDM membrane is typically a laminate of a white and black membrane. Does anyone have experience of delamination of these two layers? David J. Wyatt, CDT Senior Member Username: david_j_wyatt_cdt Post Number: 317 Registered: 03-2011 Posted on Monday, November 11, 2019 - 01:16 pm:    Dewayne, that is one progressive maintenance chief! I rarely encounter anyone in building maintenance who would do so much as clear debris from a drain, let alone attempt to re-seal a failed seam. Although, I have seen a few well-meaning folks fastidiously shovel paths through the gravel ballast of single-ply membranes to allow the roof to drain. Naturally, the shovels shredded the membranes and the warranties were voided. Ugh! John Bunzick, CCS, CCCA, LEED AP Senior Member Username: bunzick Post Number: 1797 Registered: 03-2002 Posted on Monday, November 11, 2019 - 01:25 pm:    Does anyone know whether PVC and TPO manufacturers have a method for doing small repairs without heat welding? It seems like that would be a common need. anon (Unregistered Guest) Unregistered guest Posted on Monday, November 11, 2019 - 01:33 pm:    John, Yes, most roofing membrane manufacturer's (including single ply - of all types) offer a reinforced, cold fluid applied flashing membrane (many are PMMA, some other chemical variations) that can be used for small repairs. ken hercenberg Senior Member Username: khercenberg Post Number: 1256 Registered: 12-2006 Posted on Monday, November 11, 2019 - 04:46 pm:    No delamination on my end but seam failure specifically with EPDM (both colors). One concern with EPDM is that it's the only roof with a history of failure at the seams in the field of the roof. EPDM and TPO have both been discussed as having shrinkage issues, even when reinforced. White EPDM is usually pricey, often as much or more than PVC which is typically regarded as the better membrane of the three. Dewayne, from what I recall there are thermoplastics that lose their ability to heat-weld over time (not sure if that's still the case) so repairs are often done using membrane set in adhesives (sort like a bicycle tire patch) or liquid (PMMA, liquid EPDM, etc.). William C. Pegues Senior Member Username: wpegues Post Number: 986 Registered: 10-2002 Posted on Tuesday, November 12, 2019 - 12:21 am:    To say nothing of the fact that performing ones own repairs on the roof voids the warranty. Good luck with that! Back in the 80s, some of the manufacturers data even spoke of pin holes in the membrane and you can get ponding even with slope. Some of the PVC systems that hail from a waterproofing, you can even save money by doing a dead level roof. Regardless of the code requirements for a minimum slope. Sarnafil’s PVC can do this I know. There are other membranes that can also do dead level roof. William C. Pegues, FCSI, CCS, SCIP