What will happen if I leave a ply wood half pipe in the rain?

Question

Im thinking of making a halfpipe. I dont know if I should buy a cover for it, make a cover, make it portable, or even if reain will effect it.. Help please? :)

Answer 1

it will be destroyed

Answer 2

Spend the extra money and buy marine grade plywood.  It is much more resistant to moisture than regular plywood.  It still needs to be sealed and if you want it smooth use a quality gloss latex or oil base exterior paint.  Or, marine varnish.  Regular sealer such as Thompson's Water seal will leave the same texture as the wood.

Answer 3

Left untreated, rain will destroy your hard work.  I would seal it with a deck sealant, and consider covering it with a tarp when not in use.  Try Thompsons water seal.

http://www.thompsonswaterseal.com/

Using pressure treated lumber at all points in contact with the ground will help prevent rotting, and make it last longer.

Answer 4

Hi -

I'm a skater and I used to build decks for a living, and I've built a few pipes.  Fun stuff.  A completely unprotected pipe might get you through a summer before the ply soaks up too much water and gets all warped and splintery, but if you're gonna do that much work you might as well make it last a few years.  So:

1. Use "exterior-grade plywood". You don't need "marine-grade" (which is good stuff but more $).  Good idea to use pressure-treated lumber for the frame, too.  The guys at the lumberyard will point you in the right direction.

2. Don't bother painting the plywood - you don't need it for protection with ext-grade plywood, and paint gets real slick with even a tiny bit of moisture on it (like dew) and it's hard to skate (been there, fallen on that).  Never skated on deck sealers like Thompson's, but they'd probably be less slippery and last longer because they soak into the wood.  If you use regular interior plywood (which you shouldn't), I'd soak it good with deck sealer.

3. Definitely paint or seal the frame if it's not pressure-treated lumber.

4. USE SCREWS!  Nails WILL loosen and stick up, and exposed nail heads = stitches.

5. If it's not a huge pipe,covering it with a big tarp held down with bungee cords is pretty easy and worth the effort.  You can get a 20x40' tarp for like $25 at Wal-Mart or Bargain Outlet.

Have fun!