Looking at a 2008 Fourwinds 27ft need advise

How to maintain a rubber roof

Polk's Tips from link wrote:
Another way to distinguish between the two is to see how slippery the rubber surface is when it is wet. EPDM roofing is extremely slippery when it is wet, whereas TPO is not.

I own one of each and that's the way I recall it too. It's surprising because it's the opposite of what you'd think by looking at them dry. But other links from a Google search say EDPM is not slippery and TPO is. So, I give up.
:)

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.

Snowman9000 wrote:
Those roofs should last 20 years with routine care. .

that's the issue. they require more "care" than TPO/fiberglass/aluminum ones. check the camping world catalog for stuff for the care and feeding of rubber roofs, then see what you can find for TPO. you are just buying another potential hassle that can be avoided.
bumpy

Four Winds 5000 and Dutchmen Express are the same except for interior trim. The Dutchmen I have heard is slightly above the 5000 but I have never been able to see a difference.

Mine is a 28A. I think that refers to the length of the "house" (aprox), The chassis length is more, in my case 30+'.

My rubber roof is still fine.

The Chevy chassis is rated at 12300 pounds. Slides add weight so check that there is sufficient allowance to hold everything you will be loading into the RV and not exceeding the 12300 pound limit. There should be a sticker in a cabinet telling you the GVWR and the unloaded weight.

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.

I'm of a different opinion on this than Bumpy. I would not have a problem with it even if it is EDPM. It's only a 2008, and there are tons of EDPM roofs out there giving great service. Those roofs should last 20 years with routine care. My trailer is ten years old and has one, it's in good shape. If you like the unit, go for it.

Thermoplastic PolyOlefin (TPO) is a trade name that refers to polymer/filler blends usually consisting of some fraction of PP (polypropylene), PE (polyethylene), BCPP (block copolymer polypropylene), rubber, and a reinforcing filler. Common fillers include, though are not restricted to talc, fiberglass, carbon fiber, wollastonite, and MOS (Metal Oxy Sulfate). Common rubbers include EPR (Ethylene propylene rubber), EPDM (EP-diene rubber), EO (ethylene-octene), EB (ethylene-butadiene), SEBS (Styrene-ethylene-butadiene-styrene). Currently there is a great variety of commercially available rubbers and BCPP's. They are produced using regioselective and stereoselective catalysts known as metallocenes. The metallocene catalyst becomes embedded in the polymer and cannot be recovered.

EPDM rubber (ethylene propylene diene monomer (M-class) rubber),[1][2] a type of synthetic rubber, is an elastomer which is characterized by a wide range of applications. The E refers to ethylene, P to propylene, D to diene and M refers to its classification in ASTM standard D-1418. The M class includes rubbers having a saturated chain of the polymethylene type. Dienes currently used in the manufacture of EPDM rubbers are dicyclopentadiene (DCPD), ethylidene norbornene (ENB), and vinyl norbornene (VNB). EPDM rubber is closely related to ethylene propylene rubber (ethylene propylene rubber is a copolymer of ethylene and propylene whereas EPDM rubber is a terpolymer of ethylene, propylene and a diene-component).

the dicor web site shows how to tell the difference.
bumpy

what does TPO stand for and can you tell by looking at it and why is tpo better ?

Snowman9000 wrote:
The rubber roof is no big deal! Especially for such a new unit, and especially for the TPO variety, which is a tough material. .

Is this a rubber (EPDM) roof or a TPO roof. there is a vast difference IMHO. I would accept a TPO roof, not a rubber (EPDM) one.
I see in the linked brochure it says it has a TPO roof. the Owner didn't know what he had. :s
confirm that it has TPO and go for it.
bumpy

I have had both the Chevy (in a Four Winds 28')and the Ford V-10 (Coachmen 32'). I like the the Ford better; more power and the ride feels better. The Chevrolet did have more leg room. Mileage is about the same. The Chevrolet always felt to me like it was maxed out. I wouldn't have considered towing anything with it. And it seemed to "float" suspension wise. I definitely have more power in the Ford. Both units were low mileage when I got them. Hust my opinion of course.

The rubber roof is no big deal! Especially for such a new unit, and especially for the TPO variety, which is a tough material. Maintenance is to go up on the roof, and look at the rubbery sealant which is dribbled in mass quantities around each item up there. If you see significant cracks or gaps developed, you clean the existing sealant with lacquer thinner, then dribble new sealant over the cracks or gaps. The sealant is called Dicor self leveling lap sealant, and every RV store carries it. You need a cheap caulking gun (like under $5 at a hardware or Wal Mart) to apply it.

Check those seams once or twice a year and that's it. Most people ignore it and eventually it can cause a problem. My bet is that the one you are looking at is just fine, considering its age, even if the owners didn't ever go on the roof.

The sealant is the second line of defense, BTW. There is a different sealant under each of the items that are screwed down onto the roof. So both sealants have to fail before water gets under the roof.

If you like the unit and the price, don't wait around. Nice used units go fast. Don't worry about it being a Chevy. They are good. Each (Chevy and Ford) has pros and cons. We have a Chevy. Rides and handles satisfactorily, seems to have good power, etc. I personally would rather have it than a Ford just due to the passenger leg room. But they are more alike than different, for sure.