Bought an Oneida 2.5hp Dust Gorilla 2 months ago and really love it.....except for the noise. Thinking about building an insulated closet around it, but wondering a.) how effective this will be and b.) more importantly how much open space do I need so that I don't build up back pressure from the exhaust? Was thinking about building from floor to bottom of the ceiling joists which would leave 10" openings above the wall to equalize pressure. Thoughts? Thanks for your help. Frank