I will be building my own enclosures and was wondering what size flexwatt to use. The enclosures will be 16w38L22h and two at 24w48L16h. Originally I was thinking to cover most of the floor with it. However, reading about rack systems and the smaller sizes they use I'm not sure. I was going to use 2 ft of 12 inch in the smaller enclosure and 3 ft in the larger ones. Any advice on this? Also I was planning on placing plexiglass over the flexwatt and sealing around it and drilling some holes in the bottom of the enclosure. I have read people just sealed the plexiglass over the flexwatt with no air circulation but I've also read it would be dangerous to do that.