'Liquid Rubber' paint. Any good?

[Clamity]

I'm thinking of coating my newly leaking fireglass pop-top with a coat of rubber paint. I've been told it'll stick absolutely fine to well keyed gelcoat and it'll stay flexible for many years. Does anyone here have any experience of this stuff, e.g. on flat roofs or decks or sheds, etc? How easy is it to work with?

I've looked at liquid EPDM, but it appears no one does anything other than jet black in the UK. (White is apparently available in the states which you can mix with pigment to get pale colours, but it'll cost a fair bit to get it sent here.)

So I'm thinking of using RubbaRoof which I think is some sort of polyurethane and cures to a matt light grey.

Cheers for any advice!

[composimmonite]

Why not simply properly repair the fibreglass to stop the leak ?
The coatings you describe will condem the roof to looking like a shed item for the rest of it's life which is OK if it's just a bodge to get a little more time out of a vehicle before scrapping but you might regret it if it's a "keeper". Also it'd put any future owners off if you ever come to sell.

Paul H.

BTW used the stuff on a garage roof and experience showed it ends up looking like underseal so don't expect a decent vinyl roof effect.

[Clamity]

Sept 26, 2012 19:20:57 GMT composimmonite said:

Why not simply properly repair the fibreglass to stop the leak ?
The coatings you describe will condem the roof to looking like a shed item for the rest of it's life which is OK if it's just a bodge to get a little more time out of a vehicle before scrapping but you might regret it if it's a "keeper". Also it'd put any future owners off if you ever come to sell.

Paul H.

BTW used the stuff on a garage roof and experience showed it ends up looking like underseal so don't expect a decent vinyl roof effect.

Bummer. I half thought that might be the case, but when I saw self-levelling mentioned I had silky smooth matt finish in my mind's eye. Thought it might have looked quite good.

It's definitely a keeper, but the roof's in not great shape. It's started ponding which has caused it to sag further which in turn has put stress cracks in the roof. I planned to take it off the van, replace the wood battens inside and the ceiling card to get it flat again. But the thought of having to grind out all the cracks and get a gel coat to match the original now chalky off-white puts me off a bit.

I read that EPDM roofs are pretty common for RVs over in the states, that being the reason it's generally available in white over there?

[composimmonite]

Rather than grinding out all the cracks why not encase the whole roof in a layer of fibreglass, then surface tissue followed by the type of gel coat intended for boat repair (can't remember the proper name for it).
The EPDM roof on US RV's will be for the coachbuilt Winnegago and such instead of smaller van conversion pop tops. On such large RV's they are so high nobody can see the standard of the finish.
My advise is do it properly once rather than a quick fix (bodge) and regret at a later date.

Paul H

[ben711200]

Sept 26, 2012 21:15:17 GMT composimmonite said:

Rather than grinding out all the cracks why not encase the whole roof in a layer of fibreglass, then surface tissue followed by the type of gel coat intended for boat repair (can't remember the proper name for it).


Paul H

Flowcoat?

[Clamity]

For sure. I hear what you're saying.

I used to help out repairing holes in sailing dinghies a long time ago and I just know if I tried it I'd end up with a roof full of halos and patchiness.

I never tried fibreglassing over a whole boat. I wouldn't want to add too much extra thickness/weight, I wonder if it would stick ok if I only laid it on really thin? I'd want to avoid using epoxy if I could.

Going back to your experience with the liquid rubber, how did you go about applying it to your roof? Did you have to trowel/squeege it on, or was it thin enough to brush?

[RobinJI]

Why not repair it by grinding out the cracks etc then just paint it? Then it's done properly, it looks fine and there's no real extra weight.

[composimmonite]

My roof was pourous. I brushed it on. Imagine brushing seal sealant to get an idea what it was like - stringy and doubt you'd get a decent finish unless sprayed. Then you would have a duff fibreglass roof that you could no longer repair properly ! Do it once and do it properly or you'll regret it later on.

paul H

[Midas]

I'd be tempted to repair it properly as you describe, grind the cracks, fill and paint with Jotun PB epoxy primer before top coating with whatever you fancy.

[Clamity]

Thanks for all the suggestions guys! You're giving me lots to research.

Sept 26, 2012 22:34:42 GMT Midas said:

I'd be tempted to repair it properly as you describe, grind the cracks, fill and paint with Jotun PB epoxy primer before top coating with whatever you fancy.

Having used it before I'm pretty confident doing patches with csm, polyester and gel coat. It looks like there's a lot of hairline cracking and porosity to find and fix though. What is Jotun PB? A Google search doesn't find that stuff specifically. Is it a rock hard paint or something more flexible?

I'm not sure about painting it. I'm conscious that any patches are effectively only glued in place and it really needs gel coat for an impermeable barrier. Gel coat over the patches then paint sounds like a lot of extra work. I think just going over the whole thing in gel coat might be easier.

I came across this vid. Pretty compelling, if only this stuff was available here:

[Midas]

Sorry, getting my letters mixed up, It's HB.

www.baysidemarine.co.uk/jotun-penguard-hb-epoxy-primer-5-litres-2246-p.asp