TPO and EPDM | How to visually tell the difference

[MPdesign]

TPO and EPDM | How to visually tell the difference?

Can someone please answer this and maybe post pictures?

[?[^] THANK YOU!!!!!

[hausdok]

The TPO is shiny and feels and looks exactly like a swimming pool liner with heat-welded seams and the EPDM looks and feels exactly like black inner tube material.

ONE TEAM - ONE FIGHT!!!

Mike

[Jim Katen]

TPO and EPDM | How to visually tell the difference?

Can someone please answer this and maybe post pictures?

Start with the color. Although TPO is available in a dozen different colors, it's usually white. EPDM can be either black or white, but black is far more common.

EPDM is rubber. It feels exactly like an inner tube on a tire.

TPO is plastic. It's harder and less stretchy.

EPDM has a matte surface.

TPO has a shiny, slick surface.

EPDM seams are cemented together.

TPO seams are heat welded.

[kurt]

No one described how to tell whether it's TPO or PVC.

That's a little trickier.

[Jim Katen]

No one described how to tell whether it's TPO or PVC.

That's a little trickier.

No one asked.

It's a lot trickier. Aside from the fact that TPO is *usually* slicker (not always), I look for a label somewhere. The TPO flashing boots nearly always have "TPO" stamped onto them somewhere.

The most popular PVC product in my area is Durolast and it almost always has DL stamped on the seams along with the installation date.

Also, with some products, not all, the amount of plastic on top of the scrim is less than the amount of plastic below it with TPO. Whereas, with PVC, the scrim is right in the middle.

[kurt]

That's (more or less) what I do. I still can't tell lots of times, and have to ask. I hate asking.

[MPdesign]

So, I am thinking this is TPO because:

whiter than off-white

doesn't look cemented

looks like clean seams

correct?

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[kurt]

It's why I brought it up; it's really hard to tell, especially from a pic.

Some of the Durolast jobs I see have joints as clean as TPO.

[hausdok]

No one described how to tell whether it's TPO or PVC.

That's a little trickier.

I don't try and figure it out; I tell 'em it's either TPO or PVC and if they're interested in knowing which they should find out who installed it and give 'em a call.

I don't really care. If it's right it's right; if it's wrong I write it up and let the roofing contractor figure it out.

ONE TEAM - ONE FIGHT!!!

Mike

[MPdesign]

Single ply membrane it is - for now.

I will start looking at flashing boots for TPO and seams for DO!

Thank you gentlemen.

[kurt]

No one described how to tell whether it's TPO or PVC.

That's a little trickier.

I don't try and figure it out; I tell 'em it's either TPO or PVC and if they're interested in knowing which they should find out who installed it and give 'em a call.

I don't really care. If it's right it's right; if it's wrong I write it up and let the roofing contractor figure it out.

ONE TEAM - ONE FIGHT!!!

Mike

Yeah, but it's better to be right. You know how it is; if I call it the wrong thing, then the goons get all excited about me being wrong.

I hate giving people ammunition.

[Consultant2buildings]

TPO, in our firm, is referred to as Temporary Plastic Overlay.

In Florida, when it is working at all, it will last longer than PVC. Usually.

PVC is the one that is more expensive.

PVC is more prone to splitting.

PVC sales are largely, from what we can tell, driven by the distributors. Strong distributors, strong sales, and vice versa. A lot of areas they are not selling in. Splotchy coverage, hard to know. PVC'rs don't do Residential normally.

[Greg Booth]

TPO, in our firm, is referred to as Temporary Plastic Overlay.

In Florida,..........

..........that would be the blue plastic tarps seen everywhere?[]