Definitely enclose it in for security sake and for controlling photoperiod. I have a room that's about 5x12 and when I first turned on the 1000w I said to myself "What have I done" Now I'm soooo glad. I have 8 plants and could do a few more but then it would start getting crowded. I have 1 side set up for vegging with 2-4' banks of flouros and a few cfl's.