I moved to a large apartment community of mostly 12-plex single story units with individual covered patios. It is in California so smoking, even a pipe, is regarded as grounds for deportation or worse. I want to build an exhaust fan / filter system that I can use to collect the smoke and send it up to the roof where the wind can carry it away from the neighbors. I'm thinking of something like we have in our homes over the stove: with a hood, filter, exhaust fan and flex ducting. Something I can put in the corner of my patio, power up during my pipe time, and either filter or vent away enough smoke to keep the neighbors quiet. The parts can be inexpensive and easy to assemble. I just want to know if any one here has ever tried to build something like this for an exterior patio. Thanks for any input.