Roof Material Identification Question

They need a guy up there to flash that vent pipe anyway.:slight_smile:

Before it leaks if not yet. :mrgreen:

Nice looking place but was a team flip special so I stop there.:twisted:

It looks like a vulcanized rubber roofing system that has been hot mopped in place. In any case, the scrim is visible which means that it is worn to the point it needs replacing. When I first looked at the pictures, I thought it was a modified bitumen that is not granulated, until I blew up the pictures. You can see new mod bit systems that are ungranulated and have marks from the calendar machine used to manufacture the material. Ungranulated modified bitumen is usually pretty thick and scuffs pretty easy. A good way to tell is to run the edge of your shoe across it. It has a tendency to leave brown streaks. Rubberized and plastic systems will have a tendency to leave a lighter, whiter color streak if any at all.

BTW…if it is vulcanized rubber, you would not want to hot mop it down. Roofing systems are designed to work with their own adhesives. The oils will break down the rubber and cause it to fail or not be affixed properly. If this is a new installation, some types of systems have exposed scrim, but it needs to be placed so that it faces the decking. What is visible in the picture would indicate that it has been installed upside down if it a newer material.


I will have to disagree, looks like mod-bit (non-granulated) torch down to me. It is definitely not installed upside down…note the lap mark lines. The real call-out on this one is the missing vent boot and associated flashing layer that would go on top of the boot.

I guess between the it appears, looks like, posibly is, we won’t know for sure untill a Professional roofer identifies the product and evaluates the condition of whatever it is.
It’s a trivia question. :mrgreen::wink:

You are wrong because we all know what Modified bitumen looks like and you do not see the mesh in it like here.
I put it down as unknown but possible TPO / modified bitumen type product with I recommend a licensed and certified Roofer examine and ID at the same time he repairs plumbing waste stack issue at flashing.









I’ve been wrong before, but I think what you are looking at and calling mesh, is actually just a texture the manufacturer incorporates into the membrane to help keep the roll from sticking together when it gets hot out.

OK I am often wrong so if you can get a picture link or something it sure would be great.

This type of roofing demands a specialized flashing in Montreal Quebec. Almost a gravel stopper styled flashing.
In your photos I noted weak areas. Areas of concern.
recommend caulking lifted membrane using at least plastic cement.
flashing Gravel stopper is the only one I could find. The thickness of the tar and membrane hight account for the hight of the crimped end that seals its exposed face to the elements on the flashing…
Best I could come up with to help.

Suspect: Exposed areas of concern on the membrane at the flashing.
Suspect: due to flashing deficiencies…

The red circles indicate the wrong style flashing.
The arrow is raised membrane.
Recommendation caulking with plastic cement…

Thanks Robert.
It looks like they did add roof tar patching but we still have no idea what the material is .

Marcel I have never seen that system in Quebec. Thanks for the Tweed heads up. My books came in yesterday.:slight_smile:
I am at my suppliers for the past 27 years. Its wide. Not the typical 36" roll. Typical to torch-on roofing by its thickness and glossy exterior.
Touch roofing was banned ( by-lawed ) in the early 1980’s because the technical lessons ( teaching ) to roofers where not given by the manufactures.
Many fires started due to roofers torching the product onto the parapet wall and striping boxes, sky lights ETC,. Holding the torch wrong during the " seal period."
They held the touch’s flam at an downward projection and for to long.
When the can-strip is not used on certain methods of roofing systems it allowed a void between the decking and the adjoint roofed plane ) IE: parapet wall, skylight wall, venting boxes, ETC. or when (or certian roof plains intersect due to angle change.
The flame entered the void and ignite wooden exposed fibers or cellulose insulation ( plus other ignitable material ) under the decking in the space between the ceiling and the roof deck. The fire would start and or the embers would smolder and the roof would ignite when the workers went home.
Lessons learned at the expense to the home owner.
Its OK now seeing all manufactures are giving free training and writing certifications for ones passing the simple tests or training period.

I am pretty sure this is what you have.

I think you are right Bob, I can see a similar red or orange strip in the same place on one photo. Only your hairdresser knows for sure, ah I mean roofer. :mrgreen::wink: