Generally you want to have more CFM's on the exhaust than on the intake. What is your set up like now. You are right, you will end up pushing some smell into your house.
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BlueBear Reviewed by BlueBear on . Air pressure in the grow room I noticed itā??s extremely hard to have a perfect balance of air coming in from outside and air getting out. Iā??m especially afraid of the negative air flow condition (more is coming in and less going out) as it will disperse the smell trough out the house. So I was thinking of trying to get a little more air going out than coming in to make sure the smell stays in the grow room. Is this a bad idea and if so, how can I get the exact pressure/ratio (in to out) ? Thanks Rating: 5