EPDM rubber roofing VS metal for low slope roofs

[orson]

What are the pros and cons of using rubber roofing for a low slope roof versus using metal roofing?

It's very common around here to go straight for rubber but my understanding is that metal has a much longer service life with less likelihood of maintenance issues.

[Winchester]

How low is low?

EPDM is pretty much the crappiest roof you could ever have and metal roofs are pretty much freakin' awesome.

[framer55]

What are the pros and cons of using rubber roofing for a low slope roof versus using metal roofing?

It's very common around here to go straight for rubber but my understanding is that metal has a much longer service life with less likelihood of maintenance issues.

Yes metal has a longer life. Higher price and customers don't like to pay the extra.

[Eieio]

We use EPDM rubber roofing all the time. Never had a problem with it. The installer needs to know what they are doing, but that's about it.. Guys around here will give 10 year warranties on them..

The key is maintenance on them every few years or at least an inspection of the surface

[orson]

I could be wrong but I think anything under a 3 in 12 pitch is an accepted definition of a "low slope roof". That is the cutoff point for the two categories (low slope or pitched) when doing reflectivity and heat gain calculations for roof systems.

I'm working on an attic conversion project for which this topic is relevant.

The pricing for an aluminum standing seam metal roof came about 50% higher than for a White rubber .060 EPDM roof.

The metal roof will probably have twice(or more) the service life of the rubber roof with similar thermal performance and much less(if any) maintenance.

It is also worth noting that the metal roof would surely get recycled if torn off while the rubber roof would most likely end up in a landfill (unless we see some changes in the next 20 years).

To me it seems like this makes the metal roof very desirable option, one which none of the other contractors who looked at the project even mentioned as an option.

[Winchester]

When I build my own home it will have a metal roof.

The fact the one you are looking at is aluminum and not galvanized or painted steel is pretty good too. I think it would easily have much more than twice the life of a rubber roof.

Too bad ed's not around any more... do we have any roofers?

Galvalum:

[PA Woodbutcher]

EPDM look like someone laid a giant inner tube on the roof. The rubber that I get at my supplier has a 30 year warranty. The rubber itself isn't bad in price, but the adhesive, lap cement and termination strips add up quick.

I've only did one roof in rubber and wasn't impressed. It was like July or August when I did it so it was hot. I laid it on the roof the evening before to let it relax. Got there early the next morning and swept the morning dew off and cut my edges. Folded it back up to roll on the adhesive and when I folded it back out it had grown 2 inches at least. Laid it on the adhesive and swept the top to get the wrinkles out and it look fine. Started to do the next section, turned around and the section that had looked fine, now looked like hammer dog shit with all the wrinkles in it. I finished the roof doing it the way I had been, as that was following the directions. When I finished it all looked the same as the first section and knew I was going to end up ripping it off and doing something different on my dime.

When I went back the next day, it actually didn't look too bad and only had a couple of wrinkles in it. Homeowner was fine with it, even though I was badmouthing it.:rolleyes3: The roof that I did had a mixture of new and old sheathing and I can say that it definitely looked better where the new sheathing was.

Steel......I like it fine on barns and sheds. There are a few exceptions and have done a couple that didn't look bad. Seems the higher pitched with dormers look the best, but are a real pain and expensive to do. The 4 and 5/12 ranch roofs go fast and I can do one of them for almost the same price as a standard shingle depending on the prep.

[PA Woodbutcher]

We use EPDM rubber roofing all the time. Never had a problem with it. The installer needs to know what they are doing, but that's about it.. Guys around here will give 10 year warranties on them..

The key is maintenance on them every few years or at least an inspection of the surface

Maintenance? Talk to me Rory:o

[Allrounder]

Metal roofing is the way to go. I did a ton of research when doing these projects, the owner didn't want to replace the roof again in his lifetime. Cost was only about 50% higher than shingles.

[DavidC]

The few EPDM roofs I have done were a pita to get the wrinkles to an acceptable level.

Ours get painted with SnoCoat, a white reflective coating. They recommend recoating every five years. We recommend a recoat the second year and keep an eye on it.

We've had good luck with metal roofs as long as we silicone the seams during installation. Less maintenance and much easier to remove the snow when necessary.

Good Luck
Dave

[PA Woodbutcher]

Ours get painted with SnoCoat, a white reflective coating. They recommend recoating every five years. We recommend a recoat the second year and keep an eye on it.


White on black Dave?

[Eieio]

The few EPDM roofs I have done were a pita to get the wrinkles to an acceptable level.

Ours get painted with SnoCoat, a white reflective coating. They recommend recoating every five years. We recommend a recoat the second year and keep an eye on it.

We've had good luck with metal roofs as long as we silicone the seams during installation. Less maintenance and much easier to remove the snow when necessary.

Good Luck
Dave


Same here we do white or silver.. We wait 60 days and put on the first coat and try to re-coat later in the year to check the seams..

We have not had any problems with the wrinkling, but I have seen it before on a few roofs

[Eieio]

Maintenance? Talk to me Rory:o


We usually just check the seams to make sure they have stayed together during the change in season and we wait a few months to re-coat the roof after the initial install.

[DavidC]

Yes, white on black. We can order the white roofing but our supplier stocks the black.

Good Luck
Dave

[DavidC]

Rory, How do you handle the invoicing when you wait a few months to coat the roof?

I did that once on a torch down roof. I set aside enough to make it worth coming back and the cheapo landlord took that number and found someone cheaper to coat the roof.

Good Luck
Dave

[Eieio]

Rory, How do you handle the invoicing when you wait a few months to coat the roof?

I did that once on a torch down roof. I set aside enough to make it worth coming back and the cheapo landlord took that number and found someone cheaper to coat the roof.

Good Luck
Dave

We bill all of it up front and just explain the process.. My rubber roof guy is a has been around forever.. Everyone knows someone that he has installed a roof for so it has honestly never been an issue..

Sometimes he does the second coat some times we do it.. Just depends on our schedules.. I usually go back and check the roof and look around regardless of who does the second coat..

[ParamountPaint]

We've had good luck with metal roofs as long as we silicone the seams during installation. Less maintenance and much easier to remove the snow when necessary.

Good Luck
Dave

That sounds like a good idea. Thanks for the tip! I've never seen anyone do that, but I admit that I have only been on a few metal roof jobs.

[tinner666]

Metal would last about 50 years, or more. Part of the equation in allowing room between the cleats so the panels move freely. Also, if using Aluminum, be sure the drip edge is about 5" up the roof, or more and back hemmed. Water gets in when the seams are cut off.

EPDM is good for 20+ years. I only use reinforced .060 or .090

[tinner666]

EPDM look like someone laid a giant inner tube on the roof. The rubber that I get at my supplier has a 30 year warranty. The rubber itself isn't bad in price, but the adhesive, lap cement and termination strips add up quick.

I've only did one roof in rubber and wasn't impressed. It was like July or August when I did it so it was hot. I laid it on the roof the evening before to let it relax. Got there early the next morning and swept the morning dew off and cut my edges. Folded it back up to roll on the adhesive and when I folded it back out it had grown 2 inches at least. Laid it on the adhesive and swept the top to get the wrinkles out and it look fine. Started to do the next section, turned around and the section that had looked fine, now looked like hammer dog shit with all the wrinkles in it. I finished the roof doing it the way I had been, as that was following the directions. When I finished it all looked the same as the first section and knew I was going to end up ripping it off and doing something different on my dime.

When I went back the next day, it actually didn't look too bad and only had a couple of wrinkles in it. Homeowner was fine with it, even though I was badmouthing it.:rolleyes3: The roof that I did had a mixture of new and old sheathing and I can say that it definitely looked better where the new sheathing was.

Steel......I like it fine on barns and sheds. There are a few exceptions and have done a couple that didn't look bad. Seems the higher pitched with dormers look the best, but are a real pain and expensive to do. The 4 and 5/12 ranch roofs go fast and I can do one of them for almost the same price as a standard shingle depending on the prep.

You have to let it relax for awhile in the sun. Not overnight. That tightened it up, and kept it cool.

[roofer]

Metal Roofs

Pros: long life cycle, can add coatings to help waterproof, rustproof, and extend the service life. Metal roofs can typically withstand harsh conditions.
Cons: High initial price, inefficient roofing system (you could add a reflective roof coating to increase energy savings) This all depends on if the system is commercial or residential, most home owners wouldn't want a white roof. So it would probably be best to add an Aluminum coating, which typically offers around 60 percent reflectivity.

EPDM ROOFS

It depends on the location EPDM roofs are better suited for northern colder climates, as far as efficiency goes. Black EPDM would not be a great choice in the southern U.S. Personally I'm not a huge fan of EPDM roofs, and would recommend TPO.

[WarriorWithWood]

TPO is the way to go IMO.

[deckman]

I'm always amazed when folks say metal roofs cost more than shingled roofs. I think when you figure in the cost difference between using 1x4 lathe compared to plywood sheeting, tar paper & labor you'll find metal roofs are not that expensive. Metal roofs go on a lot faster too & down here where we can get huge hail stones they last a lot longer.

[orson]

I'm always amazed when folks say metal roofs cost more than shingled roofs. I think when you figure in the cost difference between using 1x4 lathe compared to plywood sheeting, tar paper & labor you'll find metal roofs are not that expensive. Metal roofs go on a lot faster too & down here where we can get huge hail stones they last a lot longer.

I'm usually roofing something that's already framed and sheathed so there is no savings on lath.

Metal roofing here is a heck of a lot more expensive than shingles if you don't factor it over time, which unfortunately most don't.

[deckman]

I'm usually roofing something that's already framed and sheathed so there is no savings on lath.

Metal roofing here is a heck of a lot more expensive than shingles if you don't factor it over time, which unfortunately most don't.

You have a point there. I'm always doing new construction not re-roofs.

[buildpinnacle]

Dave,

Why not just use a white EPDM or TPO. No need to waste money on the reflective surface. I've laid miles of EPDM and TPO. The membranes will relax when the temps get higher and will constrict when it is cooler. EPDM is a good product if installed correctly. Unfortunately, most people don't know what they are doing. The details are in the flashing methods. I won't install anything less than 60 mill.