Hey all, I'm going to be doing a 25x30 building which I bought from U.S. Buildings (seem to be good folks) and I'll eventually be using this for a shop. The plans for this building call for a groove to be recessed in the surface of the concrete, about the size of a 2x4. Does anyone have any experience in pouring a slab with a joint like this in it? Books or other resources you could recommend on how to do this?