TPA Roofing

Steve@Advance · May 25, 2016

Anyone had experience with TPA single ply roofing?

We're looking into it for our shop roof. Had a roofer look at it yesterday to give us a bid.

Looked into this system a few years back, a roofer looked at it, said the insulation that goes under it had to be screwed down to the existing roof.

Part of the building, 100'x 100', has a cement roof, 2'x 4' panels poured about 1 1/2" thick over sheetrock. That could be screwed down, but it would look bad as the inside is exposed.

The other side of the shop, 100'x 200', is a metal roof with insulation and tar/gravel over that. Then it has been overlaid with another thin layer of insulation and an epoxy sealer. This side cannot be screwed down because there is electrical conduit attached directly to the inside, too much danger of running a screw through the conduit.

The first roofer said if he could not screw it down, he could not do the job.

The roofer that was here yesterday said he could remove the old roofing down to the metal or concrete, clean it up and epoxy the insulation down.

Any opinions?

Thanks!

DENNIS MIN · May 25, 2016

Steve,

I am not a roofer.

I did witness conduit attached to the underside of the roof. The roofers went from underneath, drilled long screws through the roof to identify where the electrical ran.

D.

Geo-TH,In · May 25, 2016

Years ago I had rubber roof installed on a commercial garage. They screwed down a black fiber and glued rubber to black fiber board. It has lasted longer than they said it would.
No idea what type roofing you are asking about.

Den N Ms · May 25, 2016

Steve,you might want to check out Carlisle SynTec roofs they will last for up to 40 years.
Carlisle SynTec Roofs

da.bees · May 25, 2016

I'm not sure why or what the issue is with screws. I've seen several membrane roofs laid over old systems including gravel and held in place with ballast. I reccomend calling manufactures for names of autorized installers. I wouldn't use an installer that isn't factory autrized if they offered half price. It is imperative to control access and make sure those such as hvac contractors going on building understand their responsability while walking and working on membrane. A screw dropped and stepped on equals a leak. Careless handleing of tools can and will damage membrane. With the # of square feet on your building I'd desinate an employee to be trained by installer. By training I'm simply talking about understanding the roof and making sure those going onto it are not damaging it. Last but very important,repair is totally different to other systems. It's simple to fill a small hole with roofing tar but tar will eat/melt a larger hole through membrane.

huntingreen2day2 · May 25, 2016

I was the one who handled the roof repairs and replacement for a 1.2 million sq ft building. After the problems with single ply roofs that were installed before my time there is no way I would put on a single ply roof and certainly not one with a gravel ballast. We ha a tornado destroy a lot of our roof in 1999. We got an architect involved due to the size of the job and local requirements. We would up with a Siplast Modified Bitumen roof and it has been a good roof. Siplast has stood behind it well with any problems we have had. Conduit is not supposed to be fastened to roof decking. Code violation. take off the existing roofs ad go back new all the way. I would sure look at marking the conduit in some way and screwing the insulation to the decking. And I agree with the other poster about making people responsible who are on your roof servicing equipment. Ballast (rock covered ) roofs are hard to find leaks in. Also leaving old roofs on makes it difficult to find leads.

rrc300 u · May 25, 2016

As a member of the HVAC trade I bet to differ with you on the holes in the rubber roof routine. A gravel ballast roof is usually put on beacuase its a cheap out for the owner of the building. With that said there are not many building owners that will pay a guy to protect his roof properly to complete a service call on a rooftop fan or heat/AC unit. I don't make holes in roofs on purpose or drop things for others to walk on and make a hole later .....but I'm not gonna dig in a foot of powder snow for the zip screw I dropped either. Im pretty sure most guys I know roll the same way. There are way better roof systems to use and not have problems that can't be found. Sorry for the rant but it's a pet peeve of mine.

Gary from Muleshoe · May 25, 2016

One of the buildings I am in charge of at work has a TPA single ply roof, I do not like it. It doesn't resist hail well at all. The school had the same roof and after three years of hail damage and flooded class rooms they went back to old fashioned tar and gravel roof. They haven't had a leak in three years. The problem with TPA is if it is warm out it will not show hail damage at all. If the adjuster shows up in the afternoon he will not see the damage. I experienced that two years ago, he wouldn't except my pictures or the roofers witness to it. Came a big snow in the fall and flooded several rooms in the building, then they had to pay for water damage as well.

JLG · May 25, 2016

I've done smaller TPO and rubber roofs (~4000sqft). I think it's a good product. All the seams are heat welded to make one solid membrane. It's easy to fix if something punctures it down the road or if you add a vent pipe or something. It's like anything else, a good installer is key. To get a factory warranty we call the factory when we're done and they send a rep out to inspect. He's pretty thorough. They also spec how many fasteners they want to see in each peice of insulation board for a given wind rating.

We don't get much hail here so I can't speak for that. I'd have thought that the iso-board underneath would have absorbed the hail. Apparently not.

I'd mark the conduit and screw the iso down. You won't notice the screws. Look up at the celing at Lowe's or Walmart, the screws are sticking down through them and you've probably never noticed. I've never done a job over concrete yet or had to epoxy the iso down, so I can't answer for that either. But if the factory has an approved method and would give it a warranty, I wouldn't be scarred of it.

Steve@Advance · May 25, 2016

Thanks for the replies. I want to do some more research, but the ultimate decision is with the owners, my bosses.

Seems each type roof has it's advantages and problems. We had a TPA welded seam roof put on the church about 10 years ago. It stopped leaks that no other roof had been able to. Only had a couple leaks and they were warrantied 100%. This type roof is becoming more popular around here. We have a lot of heat, this seems to handle it well. Tar tends to dry out and crack, EPDM shrinks and pulls apart at the seams. I am about the only one who ever goes up there, and I will have to be careful about dropping anything, and especially careful not to walk on it with metal chips in my shoes!

I want to find out what brand of roofing he is planning on using, good advise on finding out if he is a certified installer. I can also contact them about adhering the insulation instead of screwing it down. Moving or marking the conduit is not practical, it is run EVERYWHERE!

Thanks again, I'll let you know what we decide.

Part Time Pete · May 26, 2016

I'd try and avoid mechanically fastening the ISO down. Hot mopped or cold applied adhesive is a better installation.
Pete

TPA Roofing

Steve@Advance

Well-known Member

DENNIS MIN

Member

Geo-TH,In

Well-known Member

Den N Ms

Well-known Member

da.bees

Well-known Member

huntingreen2day2

Member

rrc300 u

Member

Gary from Muleshoe

Well-known Member

JLG

Member

Steve@Advance

Well-known Member

Part Time Pete

Well-known Member

Similar threads