I was on vacation last week so I built myself a collapsible spray booth. The walls are made up of 8: 45″ by 90″ panels. The corners are formed by joining 2 panels with door hinges; thus allowing the booth to be collapsible for storage. The 4 corner units are bolted together using 2 parallel boards: 1 along the top of the wall, and 1 along the bottom. The top of the booth is a single sheet of plastic film held in place by the top parallel boards.
This construction is not an original design, but is based upon the design shown here.
I create a positive pressure inside the booth with a filtered box fan blowing air into the booth. This allows me to spray solvent based finishes without the need for an expensive explosion proof fan. My modular panel design allows me to use any number of input fans and output filters. Currently I am using a single input fan above and behind the user; combined with an output filter located opposite the fan and below the user. This configuration is beneficial because it draws over-spray down and away from the user.