I'm just about ready to break ground on a new shop. I'm planning on a two-stage HF DC system that will be ported outside. The wall that it needs to go through will be concrete ICF (styrofoam blocks). I was planning on running 5" PVC through the wall since the HF DC's exhaust port is 5"... but I'm struggling to find 5" pipe. (And I need to put this exhaust pipe through the forms before I pour the concrete.)
For that short run through the wall, how big a deal would it be to bump it down to 4"?
Thanks in advance.
T