All this talk about RV roofs brings me to the one question I have NEVER gotten answered, in fact I have got an aswer at all.
What is the rubber (etc etc) roof stuff? I have owned a LOT of houses, none of them have a rubber roof, I have had: Tile, Concrete, Rock over tar, Asphalt shingles, metal both corrugated and standing seam, Sandbags (3 layers thick), Palm leaves.
ONE roof stands out: Metal! My next door neighbor had a metal roof, put on when the house was built in 1852.
The question is: WHY not a metal or fiberglass roof over the other stuff with its extremely limited life, problematic challenges, high and expensive upkeep. Or is the real answer…follow the money?[/quote]
rubber roofs are actually called EPDM (Ethylene Propylene Diene Monomer) and about the only thing they have going for them is they are cheap, and very quick to lay.
EPDM is used mainly for commercial buildings (and rv’s), like you say, good luck finding an EPDM roof on a house (except for hidden gutters). And it’s used even more so in new comm.construction simply for the speed aspect. On new construction almost all work is on hold until the roof is on and shedding water, and this is the one big advantage of EPDM, the rolls come in all diff sizes, comman size is 10 sq rolls (1000 sq feet) and a very large amount of squares can go down in a day with not a lot of manpower.
It is much faster than a torched on 2ply SBS membrane, TPO roofs, or Tar&Gravel roofs- shingles, slate, tiles are not relavent as they are for steep roofing (anything more than a 3:12 pitch) and don’t really apply to flat or almost flat rv roofs.
i have seen a few new units come with TPO roofs(Thermoplastic Polyolefin). these membranes are lighter than EPDM, and more durable. Detail work and roof seams are much better with this than EPDM cause unlike EPDM where everything is glued or caulked, it is all welded on TPO with special heat guns. Material is more expensive than EPDM right now (as it grows in use, price comes down) and the equipment to apply TPO roofs is extremely expensive. A robotic “Caddilac” welder is in the neighborhood of $15-20 grand and even the special hand welders are around $5-900 a pop.
as the price on it comes down (has only been on the market since the late 80’s-early 90’s) i belive it will soon end up on almost every rv and why not, it’s lighter and much better.
Epdm will eventually break down, it’s petro based so it can’t be stopped. Keeping a epdm roof covered (with emulsion, or as on buildings, covered in ballast rock) and supple will help prolong it’s life, but i have’nt seen too many epdm roofs past 20-25 yrs in almost 4 decades in the roofing industry. it is also very suspectible to puncture damage. i have come across cigarette burns right threw epdm roofs, even seen holes punched threw them from birds dropping nuts, rocks, sticks on them.
want longivity? hands down slate, concrete tiles. metal? ya 50 to 100 or so yrs (rust) or 200-3 even 400 yr old slate roofs still out there.
