I have one room I'm setting up in a basement.
it is 11' x 18' with a 6.5' celing height.

Would like to look at some diagrams of ventilation lay outs

basically you want to have your exhaust in a top corner, where the hot air can escape, and you want your intakes closer to the bottom so the cool air will rise through your plants as the lights heat it. this will provide fresh CO2 for them. dont make intake fans too low though....you dont want water getting anywhere near them. an additional oscillating fan on the inside will help with circulation.

your total area is around 1300 ft squared, which has to be circulated with fresh air at least every 5 minutes, which means you want to get an exhaust fan that can exhaust at least 260 cubic feet per minute (cfm). lets say you get a 300 cfm one. that means that your intake fans need to add up to 300 cfm (or a little lower, and allow some passive intake). so maybe 2 150cfms that blow in from either side of the room.

hope this helps, im too lazy to draw diagrams :-P

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I could use more info....then I might be able to zero in a bit better on an answer for ya.

IMO...a lot will depend on what/how much lighting you plan to use.

1000 watts? 10,000 watts?

ww