Do it yourselfer Dawn contacted us with the following question:
"When building kitchen cabinets, should your sides be 3/4 inch or
1/2 inch plywood?"
We immediately emailed with our recommendation of 3/4" plywood over 1/2". That's not to say you won't find some commercial cabinets out there with 1/2" construction. Our reasoning is that the cabinet bottom, back and top are typically fit into dados/rabbets cut into the side panels. Even if you make the dado only 1/4" deep, that leaves a fairly weak 1/4" section of a 1/2" side supporting the cabinet. Yeah, adjacent cabinets screwed together might not need that much meat in their sides but then it is nice to work with the same dimensioned lumber for all the cabinets.
But Dawn doesn't have to take our word for it. In the February issue of Tauton's Fine Woodworking magazine, Norm Abram describes his 20 essential tips for making kitchen cabinets. This article is based upon the multi-part "Dream Kitchen" series on Norm's PBS program New Yankee Workshop. Tip number 9 is "Make cases from 3/4-in.-thick plywood." He also recommends using prefinished maple plywood to eliminate the need to finish the inside of the cabinet. He thinks the added expense is worth it.