100% Silicone roof coat a good idea?

[dig_dem]

Hello All,

New here. I am in the process of restoring an old 25' Coachmen and am currently working on the roof.

The roof was so weathered that I elected to strip it entirely down to the bare galvanized sheet metal. Now I am looking for what to put back on top.

I have Henry 289 and 587 elastomeric that I was planning on coating the trailer with but I have also considered going EPDM (either a roll or in liquid form.) Just recently I was offered some 100% silicone roof coat (like Henry 887 Tropi-Cool)for a fraction of what it normally sells for.

I have read horror stories about using silicone caulking on a roof but I can't find anything about an entire roof coat of silicone. Has anyone tried it on an RV? I have been told that the silicone makes an absolutely awesome roof coat that will last for decades, but I am concerned about how readily it can be repaired in case of damage.

Does anyone have any experience with silicone roofing? Can it be repaired? Is it even a concern? Should I even consider going silicone?

Thanks for looking everyone.

[Gjac]

I would choose a silicone roof over an EPDM roof based on my experience with silicone rubber. 30 years ago I started using silicone rubber sheet to make vacuum bags to cure composite parts. This led to fabricating 40 ft vacuum bags for rotor blades that cured at 350 degrees F. These bags with stood 100's of cycles of 350 cures for 4 -6 hrs a cycle. bag were 1/8 in thk reinforce with FG. The roof gets hot in the sun and silicone is a much higher temp material than EPDM. I have no experience with the type of coating than you are considering only reinforced silicone shts.

[westend]

Well, I've got three years on the roof coating and no dissolving yet. I could see that it might be an issue with ponding as the UV intensity may work on it. As it is, my aluminum roof is slightly crowned, I store it leaned back and to one side for drainage, and the Eternabond protects any water issues with the trim edges.

One issue with coating aluminum roofs is that you need to remove any oxidation to get a good bond. This is especially meaningful if you have an older roof with no previous coatings. I use a commercial prepaint conditioner for oxidation removal.

An owner should also be aware that most roof coatings don't seal against water intrusion. I painted mine to keep temps down inside the trailer. At that, the white roof coatings work well.

[John_Joey]

...snip... I used an elastomeric latex coating on the roof.

If you do go this route be careful on the product you buy. Many will not handle standing water and will slowly dissolve. These are normally the places that leaks will form in the first place, not the high spots.

I tend to agree you more then likely have an aluminum roof. If that is the case then you should be able to use the silicone roof coat to your advantage after a good prep job.

FWIW, this is the product that the two fellows used in my park. Clicky.

[westend]

First, I would suggest you put a magnet on the roof material and check to see if it isn't aluminum, most are in that vintage.

I restored and coated the aluminum roof on my trailer. After caulking everything I had a few small leaks. I then put Eternabond tape on everything and no more leaks.
I used an elastomeric latex coating on the roof. It took longer to mask off the roof than it took to spray it.

Pictures:
Eternabond going on the edges--


Roof coating drying, first coat---


Good luck with your roof.

[down_home]

Silicone on such surfaces, shrinks, pulls and rolls at edges and doesn't do any all round good job, from what I've heard. No experience.
Have you considered one of the places, in MH magazine and others that spray on a roof somewhat like Rhino Liner?
I'm not recommending it nor not recommending it.

[dig_dem]

Thanks for all of the replies everyone. I will look into all of the links and suggested solutions.

I don't know what use to be on the roof. It was ivory in color, mostly chalky, some areas came up like thick pieces of linoleum. It is definitely down to galvanized steel now.

It is my understanding that the trailer had essentially been sitting out in the sun since the late 70s. So, there is very little of the roof that wasn't baked off.

Thanks again for the suggestions and links.

[John_Joey]

What is your roof (I know you said gavl steel, but really?) If rubber then you better do a little more research. If not rubber go for it (after a good prep job of course.)

Two rigs in my current park just put on some Silicone roofing. I think they may be sorry because they have rubber roofs, but they say it's holding just fine.

I was really impressed with the dry silicone that was in the waste bucket. It was nice and thick, and stretch a surprising amount before it tore. If you get good adhesion I do not see why it wouldn't last a very long time.

[wvabeer]

http://www.flatroofsolutions.com/

[wvabeer]

Don't use silicone. It won't even stick to itself very good. There is a good place in Tennessee I forgot but they sell the rolled EPDM rubber in bulk. I bought everything from them and if you have it all apart, I would look them up. It cost me about 400 to do a 33 ft camper with 90 mil. black EPDM. They do have white just not 90 mil.

[TechWriter]

Take a look at PVC roofing.

[the_bear_II]

I have used the Henrys 289 and it worked well.

The new option many are using is a Rhino Type Lining material. I wondered if the Herculiner Roll-on you can get at autoparts stores would work. There have been a couple of posts in the past where folks have used it on their roofs with success.

There is a two step process from Dicor that works really well.

I know the tropicool has been used on Mobile Homes for years but I don't know how it would hold up to movement of an RV.

[ksg5000]

No experience with silicone roof coating - but silicone tends to be problematic on RV's and I would suspect that down the line if repairs are needed your going to regret having a silicone roof.