Rubber vs. aluminum roof

[paulitzlee2]

My Fun Finder X-139 has a leaking roof which is being replaced. The repair guy suggested replacing it with an aluminum instead of rubber, which the trailer had originally.

Any thoughts on rubber vs. aluminum roofs? What are the pro/cons, etc... of aluminum roofs?

 

[webslave]

As a rule, you will find aluminum roofing on motorhomes and high end 5th wheel units (and a few of the larger high end travel trailers).

Some reasoning/pros/cons:

Aluminum /sq ft is more expensive both to purchase and to install

Aluminum has no "give" or resilience; on MHs and larger 5th wheels (and high end TTs), the framing is such that there are less "stretch" forces on the roof material. Rubber roofing material will stretch and the seams tend to stay sealed while aluminum, during torsional strain, will not "stretch" and small fractures/cracks will occur in the seam sealants.

Aluminum leaks will not show up until a greater amount of damage is done. Since aluminum is stiffer, any rot or damage under it, tends to stay concealed since it won't sag or blister up. You won't know it is rotten until you have a support failure when weight is applied to that spot.

Looks...Aluminum will dent quite easily. Hail, dipping tree limbs that tap the roof, etc. will leave dimples in the surface.

Heating affect. Aluminum roofs will make the TT warmer in the hot sun. Next time the sun is shining, lay your hand on the roof of your car and then go lay your hand on your EPDM or TPO roof...you'll get the idea. This "coolness" of EPDM or TPO tends to make sealants last longer; the chemicals that keep sealants pliant don't get baked out as quickly.

With the advent of 10-20 year lifespans of EPDM and TPO roofing, the "longevity" of Aluminum has become less important. Most folks don't keep, for various reasons, their TTs for the "average" life of a EPDM or TPO roof.

Aluminum, while denting or scratching easily, will not be penetrated by tree limbs as easily nor will it "wear" a hole in its surface as quickly. When I replaced my Sensar antenna with a Jack antenna, I noticed "wear" areas in the rubber roof material where the wings from the Sensar had "flexed" against it while bumping down the road from campground to campground. Aluminum will scratch, but, will be less susceptible to holes from such friction.

Aluminum, while more susceptible to seam failure will far outlive the softer roof materials, although it will not stay as "pretty" for as long...but, who is going to see your roof?

The most important part to me for not using Aluminum on most TT installations are the difficulties inherent in applying the aluminum roof material initially. It must be put down smoothly and secured adequately. You can't just lay down a coat of glue and smooth it down and expect it to stay. Glue doesn't adhere well to aluminum and consequently it must be screwed/stapled down and only around the edges. The leaves the aluminum free to "float" on the roof for expansion and contraction of the aluminum which, compared to the flexible roof materials, is quite extensive. The type of fasteners must be chosen with care also. You can't use regular soft steel screws or staples; they'll rust, leading to galvanic corrosion of the aluminum and this leads to small leaks around the fasteners penetration of the aluminum. Again, these leaks will harder to detect until considerable damage is done.

Now with all those, mostly "con" reasons, as applied to travel trailers of the medium size and / or lesser build qualities, in your particular application, the "cons" become less important. You trailer is small; flexing will be less of an issue. Being small, the expansion and contraction issues will be less of an issue given the smaller "footprint" of metal that will act as a "heat sink".

The real attraction to aluminum, to most people, is the "gee, it is metal versus rubber; should last forever" thinking. 15 or 20 years ago, that was a real benefit. Now, with the extended longevity of the EPDM or TPO materials, it is "less of a benefit". A properly maintained EPDM or TPO roof, for less initial cost, ease of maintenance and repair (you can "tape a patch" over a tear in EPDM or TPO much more easily and have a more lasting repair than a "patch" on an aluminum roof) has led to the reduction in the number of aluminum roofs out there. Usually, most of us, will not keep a travel trailer for longer than a "rubber" roof will last nowadays. We get bored with the floorplan, travel styles change, the number of children diminishes, lifestyle changes, etc., all tend to make us "move up" or "move down" in trailer size and layouts before a "rubber roof" wears out. From a builder's standpoint, the "value" (both cost of material and labor) of aluminum vs. EPDM/TPO installation is a "no brainer". It takes skill and dedication to detail to make a good aluminum roof installation, while anyone with a modicum of skill and/or determination can make a good "rubber" roof installation.

Just food for thought... In your instance, a lot of the cons are of lesser concern,i.e., your smaller TT won't flex as much; your smaller "area" will not have as much of "heat sink" affect, your smaller area will also be less expensive in "cost" of the aluminum / sq ft (comparably). You will still need to be doubly diligent in inspecting seams/joints/fastener areas for any signs of cracking or leakage due to the expansion and contraction of the metal that you won't have with the "rubber".

I, personally, would stay with a good installation of a high quality EPDM roof material. It will hold up nearly as long as the aluminum, will be cheaper to repair and require less "continued" maintenance as far seam and fastener intrusion inspections are concerned.

The change from many new installations of aluminum roofs to just a handful nowadays (in travel trailers and 5th wheels) reflects the cost effectiveness (both installation and maintenance) and longevity of the newer EPDM / TPO materials.

 

[fischnet]

Aluminum CAN be best

Since I now have a TPO roofed TT (I think .. my paperwork does not clearly identify what it is, but info on the Alpha site addresses "orange peal" as being TPO...), I am trying to learn about it. And I am concerned that I will have more work to maintain it than I've been used to with my previous TTs. Any experience along those lines is welcome.

From what you say, it makes sense that it would be better for maintenance...as long as you don't get debris snaggin it or poking a hole in it. But IMHO, I think the main reason it is used is cost to the manufacturer, vs. them providing a better, longer lasting product to the consumer. Easier, faster to apply, less labor cost. My previous two TTs, Popup Jayco and Trailmanor, had really superior full aluminum roofs.

The Jayco's AL was bonded to a marine plywood layer, and it was AL both inside and out. The only leak we had in 12 years was when the center seam down the center of the roof took on water. When I opened it up, it was because the seam was inadequately overlaped and minimum sealer used and NO SEALER used over the tops of any of the screws! Otherise, it was sound as a rock and I really only had to reseal any of the edge seals twice in those 12 years.

The Trailmanor roof is designed as a unified piece, with AL exterior laminated to a Poly foam core and AL channel frame members with AL on the inside ... no wood anywhere, which is the way the sides and floors are made as well. There is no way to get the kind of rotting wood damage you can get with these other trailers. But that is spendy construction and a component we gave up in compromise to move to a 'fully erect' trailer. It is frustrating that other manufactures won't take up this kind of construction so the units are more sound, solid and less prone to water damage.

 

[webslave]

Unfortunately, it is the nature of the RV buying creature... We would all love a superbly built, indestructable travel trailer with all the amenities of a 5 star hotel, but... we won't pay more than $25,000 for it or at least 35% off MSRP before we start talking about "freebies"

There are many things that a manufacturer can do to make the RVs more durable, better built, higher quality furnishings, better decor, etc. However, all that "more" means "more cost" and the RV buying public has demonstrated time and again that they won't pay for it. The "best" built trailers (Arctic Fox, Airstream, Casita, etc) are not the biggest sellers; that's for a reason. I looked at an "all fiberglass" trailer before I bought my FunFinder. No dealing on the price, limited storage (all those holes are leak points) and very limited floorplans (costs more to tool up for additional models that will reduce selling volume for each model line) and I decided that the additional maintenance was far "cheaper" in the long run to get something that I could live with (floorplan) at a price I could afford (less than 1/3 the cost of a "worse" floorplan) was better in the long run than paying a premium price for something that was going to be less comfortable (for the way we travel) for a longer time (those "high end" units will last longer than my boredom limit ) While "solid sheeting" AL or fiberglass is long lived, the manufacture of a 7x10' section for a pop-up (most pups now are TPO for the cost reason) or even an 8x15' hard-sided is very expensive. The manufacture, handling and installation of an 8x32 or 8x38 becomes prohibitively expensive for both manufacture and purchase. As you noted, even the AL roofs are subject to leaking and the best sealants will still deteriorate over time. When it is time to repair, the TPO can be replaced or patched much easier than a solid sheet AL or fiberglass. I could have paid >$57,000 for an Airstream that really didn't have the room or livability of my $17,000 FunFinder. Yes, the Airstream would have lasted to the point that my son would have inherited it, but, I wouldn't have kept it long enough to warrant the cost (I've had my 210WBS for 4 years and I'm already getting the "itch" for a new, different trailer...).

If the buying public was willing to "pay" for quality and durability, Nash, Arctic Fox, Casita, Big Foot, Prevost, etc, would have a far larger marketing share than they do. Dollar for dollar, from both a consumer standpoint and a manufacturers standpoint, the TPO roofing membrane is a good compromise of durability, ease of maintenance and the manufacturers cost for material and labor involved in its installation. Maintenance for the TPO is very simple...keep it relatively clean, watch the sharp objects and check the caulking annually...life expectancy can be longer than 12 years and very few of us actually keep a trailer much longer than that, if that long.