temp is a very hard thing to control, most people find in the end. There are many options, not a single one size fits all. For my temp issues, I ended up running an ac duct to my room. I got lucky in that the room doesn't bleed any more energy then what my house already does. It's fairly balanced.

For larger spaces, you might want a dedicated ac unit in the room. Maybe a window mounted unit or perhaps a stand alone unit that simply plugs into a 110 outlet. You can do the same again for your res with a water chiller if you find that temps are getting too hot and heating up your res water. Keeping the room cool though, will keep the water cool too. If you are unable to keep the air temps down low enough, then a water chiller could finish the job for you, only with a slightly higher ambient temp in the room.

Dont worry about sucking cold air through the lights, that's even better for them, hot air would not be, so summer time will suck there. In that case, suck the air in from your room, assuming you are able to cool the room. Same thing with ventilation. The only reason to ventilate anyway, is if your not going to use co2. Lots of people who build seriously expensive grow rooms, also plan on using co2 so you wouldn't vent those gases away from the plants. The room becomes sealed and the lights are the only thing cooled with outside air. Using non HPS lighting would allow you to keep away from heat and not need exhausting, if you can figure a way to do that. Given your space, I don't know if you want something other then an HPS in there, for large spaces they tend to work well. In smaller spaces, floros tend to work better because of the heat.
Prodaytrader Reviewed by Prodaytrader on . need advice on intake air tempt control I am building an 8x10 grow room- that will be the floor deminsions- ceiling height 8' at lowest- I plan on making an 18" flat area atop sides with an a-frame dome at the 18" area angled up 2" to a 12" flat surface- I am building inside a barn loft and have extra height- to use as hood to collect and remove outake air- i can have intake air either coming into side or thru the flooring? this palce gets hot in summer and cold in winter- I plan on first grow being winter-How do I control the Rating: 5