They are in a crawl space that is 12 x 26. I took insulation board and stapled mylar to it. The entrance to the crawl is small and full sheets couldn't be used so they were cut into 2x4 foot pieces. It looked like a mess. The sheets dont go all the way to the top so I stapled the mylar to the ceiling and drapped it down to the ground. There are big holes in the top and around the ground. It's cold in the crawl because of the winter weather, around 50-60. The 400 watt mh bulb keeps it about75-83 depending on how warm it gets outside. With the lamp heating the air it raises to the ceiling causing a vacancy where it used to be thus pulling in air from around the bottem and the hot air vents out the holes in the top. I don't think I will have a problem with stale air but it has shown me when the outside temp gets around 55-60 the crawl warms up enough that I'm going to have to get a fan.

Because this all kinda started by accident I didn't really have time to plan all this out and have the equiptment set up. I wound up with plants I realy didn't think would grow because of the age of the seeds and how they were stored. I hope to get some time to construct a proper room. The rock on the crawl floor is 3-4 foot deep near the base where it meets the full basement wall so I will eventually dig down to give myself some more height.At that time I will construct something more permenate with walls and a ducted air system with a filter for oder.