PVC Single Ply for Flat Roof

I am taking bids on a 400 square foot residential flat roof and have been doing a lot of reading. Can anyone help with these questions?

  1. Is Versico PVC a good poduct? (I think it is called Versiflex)(Not TPO which is what this company is more known for)
    (I have heard of Sarnofl and IB, Duralast, but not Versico)

  2. I am planning to use tapered polyiso insulation (built from standered size 4x4 ft. sheets). the compression strength is 20 psi. Is this strong enough to walk on, or put a 12-14 foot ladder on, without denting the surface? or, do I need a cover board of some kind placed over the insulation? (In this case, membrane would be fully adhered to coverboard)

  3. Is PVC too slippery to walk on? I do have to access this roof occasionally for maintenance of gutters, painting windows, etc.

SHW

Hope I answer all as when reply button is hit, your post is gone.

25 PSI insul. or a 1/2 inch Dens Deck and the Dens Deck probably easier to find.

Slick roof if wet or cold.

The walk pads can be as well. There are many types that are user friendly.

PVC is a good roof when installed correctly. If the details and door areas are right, you have a winner.

Rickengie, Are you suggesting that we place the DensDeck on top of 1-inch polyiso inslation (using screws and plates)? This would protect the polyiso from denting if someone walks on it or placed a ladder on it.

How do workers keep accidents down if the PVC membrane is slick when wet or cold?

Thanks.

Hi,
I think you can easily use Versico products.Versico products have a wide range of single ply roofing system to meet almost all kinds of design. It has the ability to solve your roofing problems too. Installation of PVC product for roof is also a good product. It is not slippery. PVC Products are known to be non-slippery.

[quote=“shw001”]I am taking bids on a 400 square foot residential flat roof and have been doing a lot of reading. Can anyone help with these questions?

  1. Is Versico PVC a good poduct? (I think it is called Versiflex)(Not TPO which is what this company is more known for)
    (I have heard of Sarnofl and IB, Duralast, but not Versico)[/quote]

Yes, Versico makes great products.

20 or 25 PSI you won’t notice the difference. Plenty strong enough to walk on. Is the roof a deck also? Do you plan on walking on it a lot, table chairs ect? If it is a deck you might consider another option, EPDM with a wood deck over the top, or walk way pads over the entire roof. If its just to clean gutters or wash windows I wouldn’t add the extra cost of a dens deck. Have a piece of plywood handy put a piece of outdoor carpet on the bottom side.

Yes PVC and TPO or slick when wet or snowy. If this is a concern go with a white EPDM.

Thanks, 1985
Regarding the slippery surface of the PVC. Do you think it would be safe to place a ladder on it when it is NOT wet or cold?

VersiFlex PVC is very reliable. Although I will from time to time jump back between that or Sarnofl. I usually give the customer the final say on which one they prefer, but mostly they’ll pick VersiFlex

[quote=“shw001”]Thanks, 1985
Regarding the slippery surface of the PVC. Do you think it would be safe to place a ladder on it when it is NOT wet or cold?[/quote]

I would just cut my self a nice piece of plywood about 1 1/2’ x 3’ or so, glue down some cheap o out door carpet, I would not have any concerns doing that, plus you won’t have to worry about denting your ISO.

I like PVC roofs and they have there purpose where as the membrane its not affected by grease or chemicals and pond water will not avoid a warranty. The only con I have with PVC is it life cycle. I seen 8 to 14 year old roofs become so brittle they start to develop circle cracks this is small percentage but it still a problem. This happens to due plasticizer migration from the sheet.

Good questions, I’m sure this will further complicate things:
Version is a fine company, they are the the ‘little sister’ company of Carlisle Syntec. Same products, different contractors and different branding strategies. Typically Versico contractors are thought of as ‘The B Team’ so do some research on your contractor.

Up until 2 years ago all of the PVC sold under their Carlisle and Versico names was actually manufactured and re-labeled by another company. So there really isn’t a whole lot of research or field proof that the PVC coming from Carlisle/Versico is good, bad, or otherwise- that sort of lack of history is kind of concerning to some.

Sarnafil and IB are other manufacturers of PVC, there are others out there too: JM, GAF, FiberTite, etc (Sarnafil’s G410 membrane is a nice one, Sikaplan- their low end stuff is junk).

I don’t believe you will see much of a difference between 20 and 25 psi ISO, 25psi will set you back an additional 5%. I’m a fan of coverboards, I think someone mentioned OSB as a coverboards- it actually works pretty well… Otherwise Densdeck Prime is the standard to go with. If you are going to be on your roof more then twice a year, put down a coverboard as it will be worth it long term.

PVC isn’t any more slippery then TPO or EPDM, walk pads are expensive but worth it. It’s going to be most slippery when it’s frosty out, or when wet. I’d also remind you that PVC does encourage microbial growth as the plasticisors leach out over time. So if you have shady areas that pond a little water or are slow to dry- those are going to be the slippery areas…