Looking at a 2008 Fourwinds 27ft need advise

Snowman9000 wrote:
It's glossy white (typically), almost shiny. EDPM is more of a flat white with a more rubber texture to it. There is a big difference in slipperiness when wet, but I can't recall which is which. I believe it's the TPO that is not slick when wet.

It's just the opposite. TPO is glossy and slick when wet. EPDM has a rougher texture.

Either way, I consider both to be approximately the same and both will last for many years with proper maintenance. If an owner is not willing to perform proper maintenance, it makes no difference what the roof is made out of.

There is, however, one minor advantage to TPO over EPDM and that is relative to black streaks down the side of the coach. EPDM functions by slowly breaking down over time due to UV exposure. This is normal and by design. When it breaks down, the surface gets chalky, collects dirt, and then you get black streaks down the side of your coach after rain if you do not keep your roof cleaned and properly maintained. Coaches with TPO tend to get much less streaking.

Conversely, there is an advantage to EPDM over TPO and that is relative to making repairs. TPO seams have to be heat welded in order to get a permanently sealed repair. EPDM can be repaired with adhesive, such as what you find with rolls of Eternabond. Eternabond advertises that it can be used on TPO, but I have had very poor luck with Eternabond patches staying stuck to TPO. When you put Eternabond down on EPDM, it is generally down for good.