max- I chose to veg with cfls for a couple of reasons. I started the sprouts with the HPS and they began to stretch (Its only a 150 watt) and it got too hot in there with all the lights. I'll bring in the HPS for flower to really kick up the lumens.
barry- The walls are lined with styrofoam panels. These panels are at Home Depot in the insulation department and are super cheap (like 6 bucks). I then took styrofoam boards home and cut the them to the measurements of the cabinet. They fit pretty snuggly against the wall so you squeeze'em into place. After that you take a screw with a large heard and put it through a fender washer fender washer (donut looking metal piece). The washer keeps the stryofoam from ripping right off the screw. Drill a pre-hole through the stryofoam and wood simultaneously. After that you attached the screw/fender to secure the board, tape the cracks, and your done. Might not be that clear but w..e