Shed is built, doing some more insulation/ducting tomorrow. On the topic of IR, the shed has a 3/4" OSB roof, then 3.5" of insulation, then metal roofing on the outside, and the intire inside of the shed is rigid foam board with a R-value of 7.5. So a total of 18.5 R-value, I think it would be pretty hard to see 1 or 2 1000w's through that. To my knowledge, metal roofing has a poor infrared signature...... as in hard to read, very reflective. I'm really not sure how much of a problem heli's are here anyway. I dont have a drain, but that is a nice idea, thanks. Yes, I will remember this thread when I'm toking up..... I will post all along this build/grow. Hopefully it won't annoy anybody