doubtful. i wouldnt use chemically treated lumber. dount see why dimensional or even plywood would cause any problem at all.. i use a 20" box fan and airfilters myself. ala alton brownwould the smell of the wood be imparted on the food in those dehydrators linked? I was thinking about building one (in AZ anythign to do with the sun is kind of a no-brainer, right?) and was wondering about the effects of using plywood or even dimensional lumber and the smells/chemicals that would invariably eminate from the wood or the glues used in the plywood.