Which plywood to use under sump?

[SandJ]

Which one of these should I put under my sump?
I don’t mind spending the extra $25 for the birch plywood, but if the Pine Exterior works just as well then I might as well save the extra money.
Either one will be painted white.

 

[siggy]

do they have melamine? Sanded for sure,

 

[TheHarold]

I prefer to use high quality material in general. I would feel silly using low quality plywood, only to have to redo it in a few years.

I use 3/4 Birch plywood under my sump, painted with an epoxy paint.

 

[siggy]

I used a rubber mat that I cut to size

 

[Eagle_Steve]

3/4" birch with white tractor paint from TSC lol. Cheaper, meant for corrosive fuels, and indestructible.

 

[count krunk]

Unless you dumping lots of water in the stand then letting it sit. Any plywood that gets painted will work.

Remember many manufacturers use particle board and those stands last for a long time. Stands I have (overbuilt) in the last will last for decades.

If you are getting water in your stand often, well you have bigger issues.

 

[Streetdoc77]

I prefer to use high quality material in general. I would feel silly using low quality plywood, only to have to redo it in a few years.

I use 3/4 Birch plywood under my sump, painted with an epoxy paint.

I did the exact same thing it's going to hold up for a very long time .

 

[Sierra_Bravo]

If you plan on painting it or it won't show, use the B/C pine. If you were doing the cabinet faces I'd have a different opinion. The birch is used where the plywood would be the finished exterior and typically stained. It has nothing to do with it being higher quality other than a superior finish with fewer visual imperfections. In fact, the B/C is probably more moisture resistant being exterior grade. No need to spend the extra money.

Kinda like spending extra dough for a Mahogany dining room table but then slapping a couple coats of Sherwin Williams on it.

 

[jsker]

I would suggest using the higher grade plywood, then seal the bottom board all the way around with Flex Seal. Put the board in place, fasten the board in place. then seal the inside of the sump compartment again to seal the joints with Flex Seal. The reason for suggesting the board/playwood all the way around is not one thinks when water get under the stand and the plywood fails. I was skeptical about the Flex Seal at first. When I need to seal a leak in a box truck roof a friend suggested I use the Flex Seal and It worked. It has been two years in the Florida sun and has not leaked, thus the reason for suggesting.

 

[SandJ]

Thanks everyone for the responses! Here is the stand it is going under. There will be a 2x4 base under the plywood for support.

 

[mfinn]

I have a couple stands that I made almost 20 years ago with regular 3/4" plywood.
As long as the wood is properly sealed it really doesn't matter.
If spending the extra money makes you feel better about it, then go for it.
Just remember if it isn't sealed, it will not last, no matter what wood you use.

 

[BZOFIQ]

One that's straight - just seal and paint with multiple coats to encase it.

 

[siggy]

do ypu have any of that flooring left?

 

[Beau_B]

More expense doesn't equal more better. The birch is costlier because it's finish grade, as someone else noted above. For something that won't be seen, absolutely zero reason to use birch.

I would actually steer you to Advantech or other comparable as it's more stable and water resistant by design.

 

[redfishbluefish]

There is no need for birch....that's furniture grade ply. Go with an exterior "pine" plywood and you'll be fine. The paint (or whatever finish coat you use) is what is important...and that will protect the wood. I first coat Kilz Complete and then an exterior latex.

 

[madweazl]

Red Guard can be used to create a waterproof membrane over the plywood as well (regardless of choice.