TPO or EPDM

Another option is Alpha Systems Superflex. Not EPDM, not TPO. Essentially a type of vinyl. Same length warranty although you may as well wipe your butt with any roofing warranty.

The Alpha Systems Superflex is being used by lots of builders since around 2012, so I guess time will tell in regards to its overall life. Rockwood / Flagstaff is one, there are many others.

OP here. As I noted in my original post, Dicor has three different products, TPO, EDPM and Brite TEK which is TPO with the fleece on the back.

I looked today, and my existing roof is black on the back side, indicating it is EDPM, which simply means that Thor obtained it cheaper than anything else, don't know that it is better or worse. The roof material is OK but the leak at the TV antenna was the problem. The sheathing on the roof is OSB, not Luan and it looks like I will be replacing the first 4 ft section on the right side. It doesn't look like it got into the sloped front wall from what I can see initially, I will need to pull some more staples and peel back the top sheet of metal on the front to get a complete look.

I will get it opened up next week and will know more. Just finished removing the LH side retainer and the front retainer today. Front retainer was heavily covered with butyl and I figured it was better to scrape it with it attached to something rather than trying to hold it in my hands and scrape it clean. Still have a lot of cleaning on the strips however. Need to get new filler plastic for the retainers, and new screws. Also have to locate a number of small items such as gutter spouts (old ones crumbled).

Thankfully I am working from a extended platform scissor lift. Took my Android tablet with me up the lift and watched/mostly listened to Youtube videos all day, makes the day go better.

I was just trying to get a better idea of which way to go with the material system.

Charles

It is not really felt butDicor BriteTek has a fleece type backing. Some could say that it could act s a wick.

a search turned up this previous post:

RE: TPO versus EPDM

No. I don't know what the TPO type is. I'm sure that it has a fabric backing though. In simple terms TPO is vinyl, EPDM is rubber. About 10 yrs ago Jayco for a period of time was using felt backed TPO on some models until it was later discovered that the felt was wicking in and retaining moisture. I know of no TPO membrane used today that has felt backing and given the choice would prefer TPO over EPDM. Our current Coachmen has an EPDM roof and as is typical has the odd wrinkle, our previous K-Z Spree had a TPO roof which was perfectly flat & even throughout.

bumpy

Bumpyroad wrote:

dougrainer wrote:

Bumpyroad wrote:
don't get the fleece backed variety. years back it was discontinued by at least one rv manufacturer as any tear would allow water to wick in and rot out the underlayment.
bumpy

If you tore it, then you had a problem. IF you did not fix the tear, then you had rot. Doug

are you saying that my memory is incorrect? that one mfr had this issue with felt back TPO and went to a different TPO?
bumpy

I doubt ANY OEM would stop using a TPO product with felt backing because IF the customer caused damage it would damage the decking. After 45 years in the RV industry, I can gurantee that OEM's do not care what damage by a customer will cause on the whole RV. The OEM is not liable for the damage or repair, and they will not stop using a product because of what happens AFTER a customer damages the RV. What OEM stopped using and WHO told you that? I would have NO PROBLEM using felt backed TPO/EPDM. One thing felt backed does that standard EPDM does NOT, is not wrinkle or bunch up and makes install easier. ONE Maker out of hundreds dropped the product???? Doug

I know that Newmar uses Brite Tek on their gas Class A motorhomes. I have not heard of anyone having a problem with them and they are extremely durable.

Dicor makes different products.
BriteTek has fleece backing on TPO. This is what was installed on my rig.
They have TPO and EDPM.

Do not get the fleece backing, any minor leak will be wicked in under the TPO and cause more rot.

The primary differences (as I see it) is the TPO does not chalk like the EPDM and results in less black streaks on side walls. Also, the TPO stays white whereas the EPDM can chalk to the point that the material shows the black underneath.

The EPDM may be easier to install due to strength/thickness but I'm only guessing on that point.

Whatever you do, install the new material on new wood decking.

dougrainer wrote:

Bumpyroad wrote:
don't get the fleece backed variety. years back it was discontinued by at least one rv manufacturer as any tear would allow water to wick in and rot out the underlayment.
bumpy

If you tore it, then you had a problem. IF you did not fix the tear, then you had rot. Doug

are you saying that my memory is incorrect? that one mfr had this issue with felt back TPO and went to a different TPO?
bumpy

TPO is the better way to go. You will be redecking the roof? If not, your repair will not last. Doug