08-01-2012, 11:25 AM
Home Depot (or any other big box home improvement store) might have broken pieces of extruded (pink or blue) foam. I bought 2 sheets of 2x8 that had been crushed on the corner and the shiplap broken for $10, instead of $20 each. Scraps might be had for nothing. Make them an offer - that's what I did. 
I would not use the white "beadboard" unless it is supported by something. It's not very strong.
Andrew

I would not use the white "beadboard" unless it is supported by something. It's not very strong.
Andrew
