if your plywood is sound and 1/2" thick or more, you do not need hardware cloth underneath. Make sure you screw the board down. Those buggers are powerful and can potentially tear off a plywood off a frame if it is just screwed in. If you can't rip it apart nor can racoon. But if you can rip it...
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You have a very peaceful and serene outlook on life. Your personality shows through in your backyard design and in the photos. Very nice! And I do sympathize with your dillema given your outlook on life.
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first the raccoon issue. I believe you do understand about the...