What to "paint" 1/2" OSB with for exterior use?

[newbury]

I've read several threads on here, but didn't see anything recent.
Background - I've got a bunch of "cut-offs" (~4'x~5') that I want to make into small sheds/tool boxes to put about my properties. Primary purpose is short term tool/material storage due to inclement weather, and it's Mississippi so it inclements a lot.
I'm trying a 2 coats of WHOOPS latex and also going to try 1 coat of primer and 1 coat of latex. ALL edges coated.
But I'm open to suggestions to anything that would be better/cheaper.

* WHOOPS paint is the stuff you find at the hardware store for $3 to $5/gallon because someone returned a tinted can

now it's more like $15/gallon

 

[MAX-24-Dean]

For exterior use with OSB a primer is always recommended to be applied before painting.

 

[kenacp]

Primed and two coats of latex on my box stands in Mississippi. 15 years and looking good.

 

[ponytug]

+1 on coating all the edges.

Are these use and replace items? Around here OSB doesn't fare very well in the weather, and I would have expected Mississippi to be much worse. Are you going to put anything over it? Tyvek, siding, or something that is exterior rated?

All the best,

Peter

 

[newbury]

I'd like to get 5 or 10 years out of them. I have had OSB that wouldn't last the truck ride home, and had some Advantech that lasted outside for years.
I'm mainly just checking the TBN knowledge base to make sure there's nothing new on the market. I greatly dislike finishing a project the best way I can, only to find out there was a much better way for the same resources.
Normally I disdain OSB for anything, but this was like $20 for the equivalent of 6 4x8 sheets, delivered.

 

[Cycledude]

I used OSB to cover a bunch of barn windows about 10 years ago, never painted it and it has held up very well.

 

[bigtiller]

A relative of mine built and painted a 12x16 shed sided with OSB in the early 80's. He gave it an oil based prime coat and two latex top coats. All brushed on using Sherman Williams top of the line paint.

It's still there but under different ownership since about 1990.

 

[not2old]

I've had good luck with used motor oil. Roll it on until it won't absorb anymore.

 

[ArlyA]

+1 on coating all the edges.

Are these use and replace items? Around here OSB doesn't fare very well in the weather, and I would have expected Mississippi to be much worse. Are you going to put anything over it? Tyvek, siding, or something that is exterior rated?

All the best,

Peter

OSB is not made to be left outdoors exposed to weather. Weather its painted or not.

 

[ponytug]

Personally, much as I generally like latex, I would consider using oil based primer and oil based paint on the OSB for the reasons that @ArlyA points out, I.e. the glue is not water resistant.

OSB is not made to be left outdoors exposed to weather. Weather its painted or not.

Hence, my question about whether these were disposable sheds.

All the best,

Peter

 

[nyone]

Once that paint cracks or you get a chip of OSB coming off it's all over with.

For cheap paint I would just use what ever you can find on marketplace. And or ask friends for there old paint. Every new or old home owner has the previous people paint left behind.

 

[civilian]

Nothing to say on the paint, but make sure the tops of the boxes overhang the sides. That way the rain will not off unto the sides as easily, just like the overhang on a house. Jon

 

[Cycledude]

OSB is not made to be left outdoors exposed to weather. Weather its painted or not.

OSB isn’t made to be exposed to weather but I used unpainted OSB on some barn windows about 10 years ago and other than changing color it has been holding up very well.

 

[Midniteoyl]

I have used several different 'untreated' woods outside, including OSB. The trick is to use oil based and thin it down no more than 50/50 and put a couple of good coats on so it soaks in, like a stain. Then do the normal top coats. You can prime with a good latex primer after the thinned coats and top coat with latex, if you want, or just use a good oil top coat.