Rolled Roof versus Polyglass

I need to replace a small section of flat roof - space is slightly smaller than 12’x8’. It currently has an old rolled roof. One roofer recommends Polyglass and speaks very highly of it. He does not recommend a rolled roof at all. A second roofing company seemed unfamiliar with Polyglass and spoke very highly of rolled roofs. I know nothing about roofs and am trying to find out the pros/cons of each to make an informed decision. I have a price estimate for the Polyglass roof and am still waiting on a price for the rolled roof.

One question I have about Polyglass is the heat resistance it allows. The company recommending the rolled roof spoke about installing a light colored roof to help reflect sunlight. This roof is over a small addition that does not have a true foundation. Even with insulated curtains, it gets very hot in the summer, so anything to help lower the temperature is a plus in my book. But I don’t want to make a decision based solely on that.

Any advice is welcome - I am very unfamiliar with roofing terms, so please explain what they mean to me as you use them. My home is in the Boston area if that helps at all. Thanks!

I would consider polyglass as a type of rolled roof. Other types would be torch down, hot mop and the cheap garbage you get at home depot for $15 a roll. Some other roofers only use the term to describe the really bad type though. I really doubt that your second contractor is talking about that type.

Like Island Roofer said, “rolled roofs” are garbage and usually refer to the nailable type. In the instance that this roofer is referring to torch down or a different type of ply system, then he is mistaken in his terminology. To me either one is instant disqualification. The contractor that mentioned the roll roofing should have told you the specific brand and type of roofing he was going to use. If these are your two options, then I would go with Polyglass. Now this is ONLY if you are doing the entire flat area as I am strongly against “patching” on flat/low slope roofs.
Regardless of the roof you install you will want the most energy efficient type/color possible. Every little bit helps.

Thanks for the advice! I received the full written estimate on the rolled roof today. The quote is for Flintlastic Base and Flintlastic Rolled Roofing. The quote is much higher than the Polyglass I think in part because they send out a whole crew no matter the size of the roof, and the Polyglass roofer is a smaller company - might just be one person. We are not patching the roof but replacing the entire thing. I had read online that Polyglass is meant to be a quick fix rather than used as a whole roofing surface, so I wanted some reassurance that this is a good way to go. The roofer said it is a 20-year average life on the roof (I think… I left my notes at work.)

Yeah Flintlastic and Polyglass are the same product, just made by a different manufacturer. In my opinion Flintlastic is slightly higher quality, but not by much. I can’t really imagine either of them will really outperform the other. I would tell my customers to expect roughly 20 years out of either product as well.

Thank you again for this helpful information! I live in a two unit condo association. The other condo owner has talked with a friend who works for a contracting company about about the roof. He has not seen the roof yet, but his recommendations based on the description the other owner gave him is:

Polyglass is great but unnecessary. I usually use grace brand ice and water with aluminum flashing and you’ll never get a leak. I have some spare shingles we could use to drop the price even further, I would just need to take a look at it first.

If he is talking about shingles, is he presuming this roof is sloped? The roof has a very low slope to it, but from what I understand, shingles would not be good for this type of roof. I am curious what he recommends after he sees it. My other question is this: he said if the other condo owner helps he out, he could give us a lower price. I presume if he works for a contracting company, then he is insured through the company. But I imagine my neighbor would not be covered by that insurance if anything were to happen. I wouldn’t be comfortable with that. Am I overlooking anything else that would be important to know if this gentleman came out on his own to help a friend?

OH BOY!!! Sounds like you are about to get scammed with someone who knows NOTHING about roofing flat areas. Ice and Water Shield is NOT for flat roofs and either are shingles. Sounds like your neighbor is looking for “a deal”. you are doomed from the start He has some “spare shingles”. If this wasn’t so serious I would be laughing. Why would you be looking for a way other than what was recommended to you by professionals? You have received bids from roofing contractors and advice from roofing contractors on here. Now you bring up this other owners friend who merely works for a contractor and his ideas? We have told you what we think. Nothing else to add. Good luck, you’re going to need it.

Ancient roofing proverb says: “You can lead a customer to the proper way of roofing, but you can’t make him do it.”

Please do not put shingles and ice and water shield (grace) on a low slope roof and expect it to be trouble free. That idea that ice and water shield (the duct tape of the roofing industry imo) has almost magical powers for preventing leaks is one of my biggest roofing pet peves. There is a reason the other two roofers didn’t suggest this (cause they sound like they have a clue). Stick with a product designed for low slopes.

Thank you both for your feedback. The other condo owner mentioned this friend and was working on that estimate while I was working on a second estimate on my end (giving us a total of three estimates). I was expecting a more professional estimate from the company which is why I agreed to it in the first place. I don’t think the other condo owner is just “looking for a deal” and is open to exploring all ideas. Since neither of us knows much about roofing, he thought it could be helpful to talk directly with someone in the business. My gut feeling after receiving the above information was that we don’t want to go this route. I wanted to check in here to confirm that gut feeling. I expect the friend thinks the roof is sloped rather than flat, so I am curious to know if he changes his mind after he sees it. But the questions around insurance liability still loom large.

On a side note, both myself and the other condo owner are new as of this spring/summer, so this is the first home repair we have tackled in common space. For that reason, I am giving him a little more leeway to talk with his friend than I might otherwise so he doesn’t think I’m completing shutting down any of his input. But I have already emailed him this morning to let him know your thoughts and that I will veto any suggestion for shingles. Thank you again for helping me with this decision!

Certainteed flintlastic modified
Is night and day better than Polyglass modified.
They look and install exactly the same way.
But one is inferior to the other.

Polyglass is not tough.
Too little heat and it doesn’t adhere.
Too much heat and it burns up easily.
Not a well made product.

Certainteeds is tougher and more forgiving
To imperfection welding.


GAF Ruberoid is pretty good also.

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Modified bitumen…they have a cold down. Our insurance will not let us do torch. The cold is great as long as it is done properly. In Texas anyway. Certainteed is great…

Why has no one suggested TPO?

Because TPO is splitting all over the country. And hopefully the roof was completed 4 years ago.