Flat roofing in the frigid north

Hi Pro Roofers

I am looking into rubber for my 16’x24’ flat roof.

I have heard options of a 10’x50’roll of rubber, and if they are available i would love to get a monolithic sheet that would fit right over the 16’x24’ roof.

This roof would be installed in colder temperatures, as low as -10 C. I noticed there are a couple options for installing flat roofs… I am wondering if using the glue would still work in these colder temperatures and if rubber roofs are still commonly installed during the colder months?

I also noticed that these roofs can be mechanically attached? Given that I do not want to have this roof redone anytime soon and i dont look forward to leaks, does mechanically attaching rubber roofing perform as well in the long run?

Thanks for any advice you can offer :slight_smile:

There are a couple of systems you can install if it above 40 with sun fully adhered is a good option.You can a one pc section no detail also a 2 ply mod bit[torch down] is a great system in the cold weather.As with any roofing products in the colder months follow manufactors spec also hire a qulity roofer who you feel comfortable with.


the “glue” (bonding adhesive) cant be used below 40 degrees fahrenheit

Genflex has 16.6’ wide rolls 100’ long. or 20’ rolls 50’ long.

Obviously you’ll have alot of waste, some roofing distributors around here will cut EPDM to size, so you can get a 20’ wide piece of epdm any length you want.

With a 16’ wide structure you should do fully adhered, but it’s gotta be above 40. Otherwise you can do mechanically attached, but still the seam adhesive has got to be over 40 or it’ll flash off. The solvent vapor will actually crystalize, and that’d problems man.

You can hire a roofer who can do a heat weldable single ply like TPO or PVC, which IMO is better than EPDM anyways.

can hot asphalt be applied as the adhesive for TPO or EPDM in the colder temperatures to substitute for the water based adhesives?

The glue can be used in almost any temp with EPDM “rubber roofs” get a bucket warmer or keep it in a heated area untill right before use. we installed a glue down on a commercial building last year when it was about 10 degrees and a wind chill to boot. the lap sealant also has to be kept warm obviously.

The manufacture says 40 deg F and rising. That being said we as an industry have been installing fully adhered epdm in the coldest months of the year as long as its been out. As long as the adhesives are stored in the heat and brought out just prior to use it works.
The sun will also heat up the epdm quite a bit and that will help to.
If you want to go with a mech. system then just get four 7’x 16’ sheets and put a batten in the 6" wide seams.
You’ll save a lot on glue.

if you have lets say 60 degree adhesive and a substrate of 20 degrees. does that meet the mfgrs criteria for adhesive installation. keeping the glue warm is useless unless you are also heating the substrate.the same applies to lap sealants.water cut offs,etc.

Go with IB PVC membrane. It is mechanically attached with HOT air welded seams at 1100 degrees F ( 500-600 Celsius )

Its a proven system for over 30 years and we install it all winter long without having to worry about adhesive not bonding and seams coming apart.

To other roofers - I notice a tendency on this forum from some of you fellas to start a pi$$ing contest as soon as a system other than EPDM ( Bur, modified… pick your favorite) is mentioned. This is an open forum for all to state their opinion.

We have great success with IB and won’t use anything else. In my opinion PVC is the best for the original poster, as it is 100% mechanically attached and requires no glues/adhesives , no seam tape / caulking / cleaning of the seams , etc.

TPO while being similar in its nature, I consider inferior and unproven. Also this job is pretty small, so price difference won’t be dramatic.

Good luck

Roof boss: Your right about what the manufacture states in its literature. But they still let you put it on in the cold and never stop you or pull a warranty. And like I said if you heat all the adhesives including caulks it works good and always has.
LA: I don’t have a problem with other roof systems or pvc just people who only think one particular brand is the holy grail.
I work for a major manufacture who markets most everything but coal tar and never once have I been brand specific.
As to the best roof for this guy a pvc or tpo may be but he was wondering about cold application of epdm and I said what I know. In Michigan and Wisconson we have been installing Epdm in the winter for over 25 years and if the right precautions are taken it works fine.

i have to agree,with borna roofer,because i live in maine,and use an epdm system in quite cold conditions,and have`nt had any real trouble,with clod temp. installation of that product.

WHY would you go through all the hassles and pain in the a$$ to install Epdm against MFG requirements for BOTH membrane and adhesive??

I understand that you may be comfortable installing Epdm in general. I could also see it from a perspective of a 19th century furniture maker who would place a bed-bug inside a new mattress he just finished making… I hope you get the analogy, but I am sure that is not the case here.

It is probably the unwillingness to re-train the crew, to buy all the necessary and VERY expensive equipment, just being use to doing things the old way. I understand and that is great if it works for you.

But it does not always work! Yea, you can warm up the adhesive and caulk and seam tape… but why do it all when there is an easier way that is proven to work and does not void the warranty???

To Borna: I don’t sell IB here. If you had not noticed this site is useless in terms of online marketing and sales. The threads here get about 2-5 answers per day, if that. This means that the traffic here is way low. It is also pretty much a hardcore group of members that usually talk between themselves with rare occasional visitor from outside of roofing biz (the home/roof owner).

I also have NO direct benefit from increase in sales at IB, as I’m merely a contractor.

Now about the plasticizers leaching out and membrane cracking becoming brittle - what you are talking about is pure demagogy! Yes there was a PVC mfg that made non-reinforced membrane which would crack in cold temps - so what? that was 15-20 years ago, and that was not IB. Not all PVC is the same. Every mfg has its own formulation, therefore each PVC brand is fundamentally different from one another. The main similarity is the use of vinyl and chlorine in PVC.

BTW, IB is technically a CPA membrane (co-polimer alloy) which is compatible with PVC and it is my guess they use the name PVC as it is widely recognized, unlike CPA. I am not a chemist, so dont hold me to all the formulas and interactions of elements in the membrane.

But, Borna, please provide at least one evidence of a failing IB roof. If you can’t than than you should state that failing IB CPA/PVC roof that you see all aver the place, left and right and all too often is the product of your rich imagination, and is not really happening.

Oh, and by the way, I still remember how you offered someone here to put an acrylic (or urethane) white coating on a brand new Epdm roof, to make it a Cool Roof, instead of using a roofing membrane that was originally designed to be a cool roof… so I can’t see how you can be adequate and objective when it come to advising a roof membrane.

I of course am not objective either - I prefer IB and that is my choice and I clearly state that. But I try to be rational, I prefer NOT to violate the manufacturer’s installation specs, and not to over-complicate thing when there is a simple solution…


If it is possible you could make a tent and put a heater in there to get the temp up. I recently installed a small EPDM deck(maybe 1 sq.) and tented it. the outside temp was 12-15 degrees but I ran a heater enough to get the temp up to at least 50. Turned the heater off to glue then used a small torch to keep the heat up. Worked like a charm. We do this quite often here as the temps are pretty cold in the winter.
P.S. make sure you have proper ventilation for yourself also.


It can be use with fleece backed tpo, but hot black asphlat mixed with clean white plastic sheets is something I never understood. That’s gotta be some dirty tpo when you are done.


Doesn’t asphalt destroy Tpo when the two come in contact? It sure is the case with PVC. Although PVC and TPO are two different products, both are thermoplastics, so I think effect should be similar…

I’ve never lived where it snows but when I travel I see steep roofs in the snow prone areas so I’m curious why you have a flat roof and how much snow load it collects?


Doesn’t asphalt destroy Tpo when the two come in contact? It sure is the case with PVC. Although PVC and TPO are two different products, both are thermoplastics, so I think effect should be similar…[/quote]

The Fleece is what keeps the asphalt off the tpo.

And Pvc is the most resistant membrane to oils out of all of them that’s why its on most restaurants. La you should know that.
Pvc has plasticizers in it period. They leach out and the sheet becomes more brittle and stiff as time goes on. Pvc is toxic to make toxic to weld and toxic to throw away. Theres lots of reasons I don’t like pvc. It has its place as do all systems but unfortunately its a dying product not the new way as you say. Its market share is very minimal compared to Tpo and nonexistent compared to epdm.
So if someone wants a Epdm roof or a Mod bit roof because they know they work but still would like it reflective that’s stupid to coat it? They should just get pvc? That makes no sense to me. An acrylic coated epdm system will stay white for many years as it would on a mod bit roof. Could you just put on pvc or tpo? Sure but a lot of knowledgeable customers wont use pvc and tpos to new.
And here in Michigan the majority of the commercial contractors would chose to install Epdm over any other system and not because of cost because they trust it.
And installing in the cold voids nothing as I said unless you don’t heat the products and turn the job into a mess. Not one manufacture will stop a contractor from doing it. Its common knowledge.
Hey Ive had enough of this now. I am leaving for a 10 day vacation hunting at 3am. No more roofing or roofing talk for almost two weeks. Its gonna be good.

EPDM is just faster and cheaper to put down than PVC that is why we install more of it. Why use IB when you can get Sanafil or Cooley ? Trocal was the one that would crack, I dont think there around anymore.

All manufacturers have help centers for your decision.If your applying glues at -10c then I would say you need to wait. I mean at this time every roofer wants to work and will due what they have to do to get the job done. BUT! manufacturers have their own application specifications and this also relates to warranty’s. Also keep in mind that their are 2 Types of bonding adhesive. Yellow chemical bond and water base bond. Well water and cold - you figure whats going to happen. I’ve seen many many mechanical Fastened roof systems. EPDM has the most failures to this. The fasteners are backing out of the systems in about 9 - 10 years. Asphalt and EPDM do not mix. Unless it is a flees back system. My thoughts are to contact your roofing companys in your area a Consultant may be another choice. Because their are also other Types of roof systems that could be applied. just for example. Have you thought of TPO or PVC. Both with a 80 mil material, heat welded seams and a 50 year manufactures warranty for residential roofs. Hope this does not confuse you. But the roof system that is used may all depend on the situation.

To Borna,

Yes, PVC is the most resistant to oils, yet asphalt will slowly degrade a regular IB roof. That is why there is IB ChemGuard. Still it is not a good idea to knowingly mix the two.

Yes PVC is “toxic” and so is TPO, and so is Epdm and Mod Bit, and Bur… It is the ultimate impact on the environment that i’m concerned with. The low amount of toxins released during the manufacturing and installation is well compensated my the reduction in carbon monoxide emissions. Also IB is fully recyclable and the manufacturer goes above and beyond to be “green” - here is an example: http://www.youtube.com/watch?v=SP7_8e1BNtE

As far as PVC and coating an epdm goes: many customers don’t “want” PVC due to cost. Other than that Epdm is no better than Pvc in actually it is the opposite( my subjective opinion, so lets leave it there) but when choosing a new roof and cool factor is a concern, White PVC (or even TPO) is the obvious choice vs. black epdm with white coating.

To Jim,

I agree that Epdm is cheap and probably easier to put down and THAT is the only reason it is more popular than PVC. The cost is usually the deciding factor for the customer.

Why IB and not Sarnifil / Cooley?

Well, Sarnifil and IB are very close in quality / cost / longevity. Sarnifil is more for the commercial market though and finding a contractor to do residential work using Sarnifil is difficult. It is also difficult (if not nearly impossible) to become a Sarnifil applicator. I’ve never tried, since I’m happy with IB and to me the two systems are equal. I heard from very respectable ( IMHO ) people that it is a PIA. So why bother. Maybe some day I will…

As far as Cooley goes - NO way! Why would you use a product that manufacturer stops producing ( guess why )? It is my understanding that they had problems with their PVC sheet. Their sales “manager” told me two years ago that at that time they were not making any PVC, but were working on it? If it was a good sheet, why not make it? Purely speculative but I don’t want to put my name behind problematic product.

PS, I actually went to their HQ in Pawtucket RI to talk to them and see what they have, and talked to a guy there. I can dig up his name as I still have their brochures with his card in my basement somewhere.