Houseboat roof paint questions

[nopeda]

Hi,

I've used some figerglass cloth and West systems fiberglass resin to repair a couple of sections on my houseboat's roof. It came out good and strong and hard though it's beginning to yellow. I don't really care about the yellowing but am afraid the UV from the sun might be breaking it down. Can anyone suggest a good economical paint to use on it? Does it matter what type of paint? Since it will be on the roof it will need to hold up to some foot traffic. But it doesn't need to add strength like gel coat since the fiberglassing seems to have that part covered.

Thanks for any help with this!
David

 

[rwatson]

The UV from the Sun IS breaking the Epoxy down.

At the cheapest, a good quality undercoat/primer and an exterior house paint would work fine.
At the best, your local boat shop or auto shop will sell you two part, high build systems like Awlgrip , various truck bed products and the like.

Its probably not worth suggesting particular brands, as your local suppliers wont always stock everything. You may not even have a boat shop in your area.

Its probably best to find out what options you have, and then come back and ask any questions about specific products.

 

[Blueknarr]

David

Welcome to the forum.

The yellowing is the epoxy being broken down by UV. So paint it asap.

Do you measure cheap by initial price or long-term investment? The lifespan of paint is directly proportional to its price. The cheapest latex will need to be repainted in only two years. With all the cost of preparation. Catalyzed polyurethane may cost ten times more, it will last longer than two decades with only a single prep. The lifetime cost is half for the actual paint and one tenth on reaplication costs.

Rustoliem is readily available at the big box diy centers and elsewhere for around $40 gallon. It behaves well enough for amateur application and should last five to seven years if you don't use any non-skid particles. Paint is always worn off of the aggregate quickly.
Good luck

 

[ondarvr]

Porch paint works well and is cheap, so are the Rust-oleum products.

You can make this easy and cheap, or more difficult and pricy, the outcome in this application won’t be that different.

 

[JamesG123]

They make a rubberized roof coatings that is thermally and UV stabilized, since its designed for flat roofs. It can hold up to "some foot traffic".

BTW- gel coat provides zero strength to a composite.

 

[nopeda]

The cheapest latex will need to be repainted in only two years. With all the cost of preparation. Catalyzed polyurethane may cost ten times more, it will last longer than two decades with only a single prep. The lifetime cost is half for the actual paint and one tenth on reaplication costs.

Rustoliem is readily available at the big box diy centers and elsewhere for around $40 gallon. It behaves well enough for amateur application and should last five to seven years if you don't use any non-skid particles.

Thank you folks for your help with this! What sort of prep needs to be done? I'd rather not use rubberized or truck bed type stuff. I know nothing about paint so I guess to start I should look up the difference between latex and polyurethane. The prep thing is a concern though, and then what about later when it needs to be done again? Does the resin need to be done again too, or should it be okay as long as the paint holds up?

Thanks again!
David

 

[ondarvr]

All of paints will have instructs for the required prep work, either on the can or their website.

The lower cost paints are fairly easy to use and touch-up later.

 

[Blueknarr]

The epoxy should hold up for many decades as long as it is covered with paint.

The minimal prep would be to wash, scuff (sand) then wash the sanding dust away immediately before painting. Sanding a dirty surface grinds contaminates into the surface. Additional prep will yeald great cosmetic dividends. How good do you want the the roof to look?

Ondarvr's suggestion of porch-n-deck paint is the only water bourne paint I could endorse. It will roll smoothly on horizontal surfaces but will run like the devil if used vertically. It won't be as shinny as an oil based paint but will clean much easier than any other water paint. As a bonus, it rarely requires priming.

Rustoliem forms a harder shell and will hold a higher gloss making it easier to clean and more stain resistant than the p-n-d. Unfortunately, it is also more toxic.

Save your self from the frustration of trying catalyzed paint on your first project.

 

[nopeda]

Went by Sherwin Williams today and the girl had to call their help people. Came back and said the porch and floor paint wouldn't adhere to fiberglass so suggested some indoor gel product and to cover it with a clear outdoor product. I don't like that idea much.

Then went to West Marine and they suggested Petit EZPoxy Topside paint. Polyurethane, 32 oz for $50. Then that needs a 3021 performance enhancer for another $35 for a small can of it. And that stuff can't be cleaned up with water. Hopefully when I'm off work on Tuesday I can go by Lowe's or Home Depot, or maybe Ace hardware, and find the type of porch and deck product you people have told me about. Can anyone suggest something more specific to ask about to make sure it will adhere to fiberglass resin and can be cleaned up with water? I don't know anything about types of paint.

 

[Blueknarr]

Behr P-n-D will stick to FG that has been sufficiently scuffed (60 grit). All paints need scratches in the fiberglass to mechanically hold on to.

Sherwin Williams is the world's largest paint producer. Their industrial decision caries a great water bourne DTM (direct to metal) it would be a better choice than Behr's P-n-D. Unfortunately it is labeled "for professional use only, not to be sold to general public" and isn't usually stocked in their retail stores.

 

[rwatson]

"porch and floor paint wouldn't adhere to fiberglass"

That's why I said, you need a good undercoat/sealer if you go the "housepaint" route. I have found the ones they recommend for bathroom/ wet area use to work fine for many years. You can get more specialised ones from boat shops.

 

[ondarvr]

All these paints bond very well to epoxy, and porch paint will last a very long time.

Prep work is needed with just about every coating, primers help with the bond.

The single part “marine” paints like Bright Sides aren’t very durable, as a deck coating they’re a waste of time and money.

 

[Mr Efficiency]

100% acrylic latex house paints, particularly the "oil fortified" ( self-priming on most surfaces) variety, have good adhesion to most clean surfaces, and last many years.

 

[JamesG123]

100% acrylic latex house paints, particularly the "oil fortified" ( self-priming on most surfaces) variety, have good adhesion to most clean surfaces, and last many years.

Just beware that they take an extended time to fully dry and gain final adhesion and toughness. Up to a month depending on the weather, not the "seven days" promised by the mfg...

 

[Mr Efficiency]

Just beware that they take an extended time to fully dry and gain final adhesion and toughness. Up to a month depending on the weather, not the "seven days" promised by the mfg...

They do take some time to fully cure, but are safe to withstand rain etc after a couple of hours, under average drying conditions. Certainly about a week is needed till they become fully "tack free" to walk on.