Forum Discussion

barmcd's avatar
barmcd
Explorer
Nov 03, 2015

Roof Construction--Pros and Cons?

Up to this point we've only owned a trailer and 5th wheel and both had a rubber roof. We didn't have problems with either RV and maintenance consisted of replacing the caulking every 5 years.

I notice motorhomes come with aluminum, fiberglass and rubber roofs. I understand the construction of a rubber roof and assume fiberglass is similar in that its either one sheet or several sheets bonded together to make a solid roof.

What about aluminum? It's not one large sheet of aluminum is it? I assume its several sheets bonded together somehow. How are the seams between the sheets sealed.

More importantly, what type of maintenance is required on a fiberglass or aluminum roof?

18 Replies

  • my first two RVs had a rubber roof. my next two had fiberglass. Never again on rubber.
    bumpy
  • My Winnebago has a fiberglass roof. It is not the roof material that is the problem, it is the seal at the air conditioners that presents the problem. The ac perimeter seal leaked slowly and got into the roof deck and caused rot. I noticed the deck starting to sag in spots and get a little spongy. Probably the best roof material as long as the perimeter is well sealed. The weight per square foot would be negligible to other systems. The puncture resistant is far superior.
  • Effy's avatar
    Effy
    Explorer II
    They all have seams so all need to be checked and caulked so no win there either way.

    Fiberglass is said to be superior but there are units that they peel back and when it does break/crack it's a lot more expensive.

    TPO does produce more dirt and streaks but when it gets damaged it's a lot easier and cheaper to repair.

    TPO roofs are VERY durable and will withstand a lot of abuse and time. Fiberglass although a solid roof is very thin.
  • Our last two coaches have had a fiberglass roof. I would not have anything else. They are very easy to keep clean as there is no friction on your wash tool like you have with rubber. As far as maintenance you only need to check your calking once a year. I have found that you get very little streaking from a good fiberglass roof. Tiffin uses fiberglass on all of its models. Good luck with your search.
  • WyoTraveler wrote:
    It is getting more difficult to find fiber glass roofs on any RV except diesels. I am assuming that is because it is cheaper to construct RVs with rubber roofs.


    Fiberglass is also heavier than EPDM, cutting into cargo capacity. RVs built on heavier chassis tend to go for a fiberglass roof.

    We are very happy with our EPDM roof. We used to be boat owners and know fiberglass issues very well.
  • My 43 years conversion has aluminium roof and fiberglass caps. Caps have been painted and although they don't shine anymore, beside caulking around windows did not do any maintenance.
    Did nothing on aluminium plates in 10 years of my ownership, but I keep the coach in carport, so not exposed to sunshine who is main RV killer in CA.
  • We have a fiber glass roof. Front and rear cap are where problems can occur plus other problems that all roofs have. I prefer a fiber glass roof. That is just a personal preference. It is getting more difficult to find fiber glass roofs on any RV except diesels. I am assuming that is because it is cheaper to construct RVs with rubber roofs. Therefore, if I was looking for another RV I would offer less if it had a rubber roof. Not because of quality difference but only because it was cheaper to build.
  • Our first TT and Camper both had aluminum roofs. The seams are folded to bond each sheet together. These seams did require sealing every 5 years or so.

    We now have a 5th wheel that is 21 years old with a rubber roof. About 2 years ago I had to have the roof sealed because it was showing signs of possible leaks. This year cracks have opened where the roofing membrane rolls over at the sides. I've used eternabond tape to seal these.

    My fear with fiberglass is that 10 - 20 years down the road it may become brittle and the gel coat will breakdown. It's not a problem since most RV'ers don't keep their RVs beyond 10 years. The 2nd or 3rd owner would have to deal with it.