u need an exhaust fan more important than a intake, for the intake u can just have an open hole and let the exhaust fan pull in fresh air...u need air flow my man, they say u have to move atleast 3x the amount of space u have in a minute..example....so a 3x2x5 room will have 30 cubic feet...u need atleast a 90 cfm (cubic feet p/ minute) of air transfer in there...