The less the amount of seams, and the fewest the number of protrusions through the roofing (ac, vents, lights etc), the lower will be the probability of a caulking failure and subsequent leakage. An arched roof will shed water easier than a flat roof. A roof with seams on the sides instead of at the top sidewall/roof transition, will usually have fewer problems. A roof made of the same material as the trailer body, will have the same expansion/ contraction ratio as the body. A different material, fiberglass etc, will have a different rate and can open at the seams when the caulking fails.

Every trailer needs maintenance. If you ignore it, you will have problems regardless of what you purchase.

I have a Gore with a single piece roof, never have or seen a single drip/drop of water leak inside....  Wish my other aluminum roof trailers were as dry...

CM were a disaster. Anybody have a solution for those?

Elastomeric coatings

Thanks for the reply, Gard.

Elastomeric Coating didn’t work for me. CM had local auto body shop apply them to my roof as “THE FIX”.  (No horse trailer dealership near me wanted to do it.)  A year later after a few trips up and down the road and the affects of the UV rays, I had a leak. I called closest CM dealer about repairing the repair. They told me to call CM again. This time CM told me, Sorry Charlie, “THE FIX” had already been done. When I expressed my disbelief they said, well it is out of warranty. So I guess “THE FIX” is just meant to get them beyond warranty and now it’s the customer’s problem. The exterior of my roof looks like one big sine wave that is in constant flux. The coatings continually dry out and crack, and subsequently leak in the low spots. I have been chasing the leaks and spot reapplying coating. Other than the poor idea of a roof, I love this trailer and want a real solution.  

Thanks for the reply, Gard.

Elastomeric Coating didn’t work for me

There are various qualities of Elastomeric products, and the attention affording their installation, can result in various results. The area to which it is applied, has to be first cleaned and free of any contaminates, conditions which preclude the proper bonding of any secondary coating product. Some coating manufacturers require a barrier coating or primer. Some products are warranted for a couple of years, some a decade. Obviously the better products reflect their superiority with a higher purchase cost.

How many coats were installed? How well was the surface cleaned and prepped? Was the product installed as a sealant or merely as a painted coating? How well was the applicator's attention to detail? Was the coating a quality product or the least expensive available?

There are many variables when any type of coating is secondarily applied. If the application is done well with quality products, you will be pleased with the results. If the job is quickly and inexpensively effected, only to release the dealer/manufacturer from unwanted criticism, you may have the results that you are now experiencing.

When properly utilised, these products work well on various surfaces, for long lengths of time. Most can be repaired and recoated as they degrade. You still may be able to have your roofing issues addressed by someone other than the dealer, who has a knowledge and will to properly address the situation. You might be better served by contacting some roofing company representatives, that specialise in metal applications.