Roof Chalk Substance

[smarcus]

Thank you in advance for the great knowledge that this forum brings together.

New roof on a single family. The developer said the roof was "rubber," and then insisted it was rubber when i said i thought it looked a lot like a mod bit. Chalk is fine and smooth. The second image is a blow up of the first and you can see some of the roof texture near the seams. There was no crazing, the seams were all holding, and just a little ponding at the valley. My thoughts are that the plastics are hardening from UV rays. I have seen a little powder on mod bit roofs before, but not this heavy, especially because It rained pretty hard here yesterday, so the chalk may have run from the roof and reoccurred. Is this normal aging or is this roof wearing faster than it should be.

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[Scottpat]

Is this a manufactured home?

It looks like a poorly installed EPDM membrane and it looks older than one year!

[caryseidner]

That is app mod bit. The white powdery stuff is talc to keep the sheet from sticking to itself when it is rolled up. Pretty crappy looking installation. Looks like they re-roofed right over shingles.

[kurt]

What Cary said.

Woof, what a POS.

Do not feel even the slightest hesitation at calling this mess for what it is.

Dismiss anything the "developer" has to say regarding any aspect of the work; he's clueless.

[John Kogel]

I'm thinking that roof was done in cold weather and the membrane was stiff, so it didn't lay flat. That also means it isn't fully adhering to whatever is under that mess. The extra strip laid in the valley on the right is a warning that something is wrong there. It is a temporary fix. Time will tell how long it lasts.

In all fairness, it would be hard to do a nice job on that roof. It is ugly by design.

[Marc]

Improperly flashed penetrations/openings in the roof.

Roll should not be contiguous across a valley.

Excessive bleed-out in some places.

I don't see granules on top, for UV protection of the mod bit.

Damaged roof surface.

Uneven roof planes.

What else?

Marc

[Tom Raymond]

Any manufacturer info on it anywhere? I'm sure the local Rep would love to see how the 'developer' is misapplying his product.

[kurt]

It looks like stuff I see all the time......bungalows with "pop up dormers", where the rafters are cut and the whole mess is jacked up to provide a minimalist 2nd fl. with minimal slope/pitch.

I think Cary is right; it's laid over some previous roofing. In addition to the roof covering, I suspect (know) the roof structure is inadequate.....most likely the original rafters simply jacked up to provide a new roof line.

[caryseidner]

Improperly flashed penetrations/openings in the roof.

Roll should not be contiguous across a valley.

Excessive bleed-out in some places.

I don't see granules on top, for UV protection of the mod bit.

Damaged roof surface.

Uneven roof planes.

What else?

Marc

Actually, the penetration flsahings look pretty good. The only thing I see, or maybe don't see (can't tell for sure) would be the football patches on the corners of the base flashing for the chimney.

The bleed out is excessive and a problem.

Roof granuales are not required, nor can the be added to the sheet surface in the field. They sometimes sprinkle loose granules into the bleed out of a granulated roof, but it is purely cosmetic. UV coating is not required either.

Both of those are just upgrades. Smooth surfaced APP Mod Bit, like seen in the photo, typically come with a 10 manufacturers material warranty and surfaced (gran. or UV) have a 12 year...if the UV is reapplied when is degrades (ave. 4-6 years). Mod Bit is a fine product when installed properly and on the right structure.

Problem is, we rarely see a good installation on the residential side. Commercial is a different story.

[caryseidner]

I'm thinking that roof was done in cold weather and the membrane was stiff, so it didn't lay flat. That also means it isn't fully adhering to whatever is under that mess. The extra strip laid in the valley on the right is a warning that something is wrong there. It is a temporary fix. Time will tell how long it lasts.

In all fairness, it would be hard to do a nice job on that roof. It is ugly by design.

What is wrong is that the valley should have been installed under the field sheet. In fact, if they would have laid the valleys 1st and then ran the field sheets into them the whole roof would at least look and lay better.

I'm guessing by the sheet layout that this roof was installed by a guy who is used to running a lawn mower.