Best wood type for flat roof

I am redoing a flat roof on a vacant building from the beams up. First the plywood then the rubber, etc.

I laid 3/4" CDX pine on the first area. Forecast was for rain so I applied a wood preserver. Then the rain came. Now I see the wood is swollen and blown up in the corners and is sort of opening up and coming apart.

Any suggestions on a better type of wood than 3/4" CDX to use? Please respond ASAP.

Thank you.

you never,ever leave any deck exposed to the you will need to replace those sheets.have you ever installed rubber before?

Morning wood.


CDX is the best.
However, no matter what you put on it can not get wet. You also have to be careful about the water proofer. it can react with the roofing material as well as vent fumes into your attic. I bet there is something that causes cancer in california in it. Just because the building is vacant doesn’t mean you can slack. still have to keep it water tight

wood preservitive? LOL

Preserver? Yikes… this is a roof deck, not a BBQ deck.

If you’ve got a problem with rain issues (we’re crazy with rain here in Central Texas lately) then I suggest you simply tarp it over with as much of a layover off the sides as you can (depends on the size, of course). You can even weight the grommets with rope tied to lumber on the ground.

Otherwise, 15# double lapped with (again) a long layover off the sides.

Either that or wait for 2 days without rain.