What type of roof is this? - InspectionNews

Matthew Barnicle · #1 (**permalink**) 05-08-2008, 01:01 AM

What type of roof surface is this. I am thinking PVC???

Richard Moore · #2 (**permalink**) 05-08-2008, 01:08 AM

Looks like EPDM or Thermoplastic. Take a look at the Firestone site.

Firestone Building Products U.S. - TPO Roofing Systems

Jerry Peck · #3 (**permalink**) 05-08-2008, 07:20 AM

I'm guessing it is TPO.

They do make EPDM with a white top layer, however, most EPDM is black.

I haven't seen PVC used for roofing in over 15 years, but they may still use it (although EPDM replaced most of the PVC, and TPO is replacing most of the EPDM).

Rick Hurst · #4 (**permalink**) 05-08-2008, 08:00 AM

Copper and coil thieves would be busy all night on that roof.

Jim Robinson · #5 (**permalink**) 05-08-2008, 08:05 AM

All the EPDM out here is white, for obvious reasons. I've got it on my rental property, and there are quite a few around town. A black roof here would be a nightmare. I haven't heard of TPO. What's that stand for?

Rick Hurst · #6 (**permalink**) 05-08-2008, 11:41 AM

TPO stands for Thermoplastic Olefin or Polyolefin

rick

Jim Robinson · #7 (**permalink**) 05-08-2008, 01:02 PM

Does the TPO look just like the EPDM, or is there a way to tell them apart. Just in case I run into it one of these days.

Jerry Peck · #8 (**permalink**) 05-08-2008, 05:26 PM

Quote:

Originally Posted by Jim Robinson

Does the TPO look just like the EPDM, or is there a way to tell them apart. Just in case I run into it one of these days.

EPDM is stamped with the manufacturer and the thickness along the edges of the roll (and sometimes in the center field areas) as I recall. EPDM is 'usually' always black.

TPO is harder to identify as the labeling disappears into the white color (all TPO I've seen is white, some is white through and through, some is black underneath and white on top).

Cary Seidner · #9 (**permalink**) 05-08-2008, 10:33 PM

It's TPO. You can tell by the heat welded penetration flashings.

Jim Robinson · #10 (**permalink**) 05-09-2008, 07:21 AM

The membranes here in my town were put on by a company using the Duro Last roof system.

Commercial Roofing System Single-ply membrane roofing system - Duro-Last Roofing, Inc.

I thought it was EPDM, but from reading their web site I see that it is actually a polyvinyl chloride blend. I guess that makes it a PVC roof, or is that a different product? It looks a lot like the roof in the photo. These aren't put on with heat. They use a glue, much like a swimming pool liner.

Cary Seidner · #11 (**permalink**) 05-09-2008, 07:33 AM

It's really hard to tell without a close-up shot of the membrane, but in the first photo I see manufactured (as opposed to field fabricated) penetration flashing. Really looks like TPO to me. TPO, PVC and EPDM are all membranes in the "Single-Ply Roofing System" catagory, and that is what I would call it if I could not conclusively determine the type.

Jerry Peck · #12 (**permalink**) 05-09-2008, 08:02 AM

Jim,

Reading through some of those specifications, I think that might be a PVC roof system.

At first, it looked like TPO, but reading their information, I'm thinking PVC.

Jim Luttrall · #13 (**permalink**) 05-09-2008, 08:44 AM

[quote=Jerry Peck;43019]EPDM is 'usually' always black.

quote]

Jerry, is that anything like "Jumbo Shrimp"

Matt Fellman · #14 (**permalink**) 05-09-2008, 01:54 PM

That looks just like what's on my RV. RV people always just call it a rubber roof. Are the terms you guys are throwing around just more specific or is there a difference?

Jerry Peck · #15 (**permalink**) 05-09-2008, 05:02 PM

Quote:

Originally Posted by Matt Fellman

That looks just like what's on my RV. RV people always just call it a rubber roof. Are the terms you guys are throwing around just more specific or is there a difference?

The "rubber roofs" on many RVs are EPDM, while many others are TPO. You need to know which before making any repairs as the sealants are not compatible with each other.

Larry Wilson · #16 (**permalink**) 05-09-2008, 07:07 PM

Hi guys, whichever it is, it would sure be nice to know who put it on. From the pictures it looks like they did a super job and I have a guy who is looking for someone to re-cover his industrial building. I did notice in the blown up picture on the left that there appeared to be a small cut. Did anyone else notice that?
Thanks
Larry W.
South Carolina

Jerry Peck · #17 (**permalink**) 05-09-2008, 09:03 PM

Also of note: See all those nicely flashed electrical conduits sticking vertically up with liquid tight connected to the tops of them?

Yep, you've all seen those liquid tight fittings fail and/or the liquid tight pull out of their fittings ... what you have now is called "a rain water raceway directly down to the electrical boxes and out into the ceiling(s) below".

Those should have (no code requirement, just common sense) had a 90 sweep on them or an LB, something to allow for the connection to be either 90 degrees to the horizontal or facing down, creating a drip loop to keep water out.

When they have a leak, that is the first place I would check for water entry.

Ken Bates · #18 (**permalink**) 05-10-2008, 03:41 PM

I read a blurb about a recent addition to the class of white reflective, polymeric membrane claddings a few months ago. So, I think there are at least 4 being used.

In the Boston area it's almost always Sarnafil, which actually predates EPDM by a few years. Sarna, a Swiss company has only 3 plants worldwide. The original in Switzerland, another in mainland China and a 3rd a few miles from Boston.

Sarna embosses their trademark on the membrane (approx. 1/2 sq. ft) but it is subtle.

Craig Olsson · #19 (**permalink**) 05-11-2008, 04:27 AM

Another possibility is PIB (Polyisobutylene). See Roof Choices - PIB for a brief description.