Cerberus...Reply on flat roof options


#1

Thanks for your reply. I appreciate it. I am close to making a decision. As to the choice in Florida between a gravel top or a modified bitumen cap sheet…Of two roofers I contacted, one of them was partial to modified bitumen cap sheet and the other suggested the gravel top. He said that the problem with modified bitumen cap sheet is that a) it gets moldy due to water puddles and 2) he thought that a more flexible cap sheet (like a mineral surfaced cap sheet) might be better in a windstorm.
My flat roof is 1800 s.f. and as far as I know does not have any excessive water puddles. But it is a flat roof and is bound to have some puddles.

You use the letters “APP” for the modified bitumen cap sheet. Is that significant because my estimates do no use those letter.

About foam roofing. It appears that Aaron was recommending it also. There are full page ads on foam roofing in the Miami newspaper.
But they indicate that they do commercial roofing. None oof several regular roofers that I called seem to be into it. I will check it out again.
Thanks…If you want my E mail its…sarafamily@att.net


#2

I am not cerberus, but I did not make a recommendation in your oeither of your other threads.

I have never seen a moldy modified bitumen capsheet.

Modified bitumen is more flexible and resilient than mineral surfaced roll roofing.

APP states which of the two popular polymers are modifying the bitumen to acheive these results. APP…he’s going to torch weld it to the BUR.


#3

Aaron pretty much covered it. I too wouldn’t worry about the “mold” on the modified bitumen. I believe what they are talking about is the same as what can be seen on shingle roofs. Bottomline, in my opinion an APP (atactic polypropylene) modified bitumen will be your best bet for covering a built-up roof membrane. Just remember to periodically have someone inspect your roof (regardless what system you go with), and to perform maintenance as needed (coatings, repairs, etc.). This will be the best thing you can do for your roof. Too often a roof is out of sight, out of mind. Consequently, people don’t think about their roof until it leaks, and by then there is extensive damage.


#4

well said