by bbarry » Thu Feb 19, 2009 8:56 am
I extended 6" front and rear as well as 4" on each side without any framing. I did use 3/4" ply and ran a 2x2 nailer along the outside edge all the way around. This gives me a place to attach the wall and stiffens up the ply a bit too. There is absolutely no deflection in the ply at the edges.
When you think about it, cheap 3/4" underlayment often spans trusses or joists at 24" with little deflection. A few inches outside of your frame especially if using good quality 7ply+ plywood is really no big deal.
Just my two cents,
Brad
Brad
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Jack of all trades, master of none.
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Kampster build thread