I think u had the right idea, there's no wrong way to do this just what works for you. You need recirculating air no matter(unless u use co2) what so u should have laughed at him. You may not need to vent the hood if u need heat. so u can take the ducting off on cold cold nights. U might as well set up your ventilation in one strait shot. You would use separate ducting for the hood if u were really fighting high temps + venting for the room w/ a scrubber.

I would do this, connect the venting from the hood to a inline, then to a scrubber in the attic. Is the attic sealed off from the garage? As for intake its up to u. where ever will keep the room cool but not to cold.
JackdaWack Reviewed by JackdaWack on . Ventilation Question I have a 6' square area that is about 6 feet tall for my grow room. I have a air cooled 600 watt hps/mh light. The grow room is located in my garage which has no ceiling and thus is exposed to the attic as well. I will be sealing my grow room off with a set of doors on the front much like a closet or something. The salesman at the local hydro store told me that the best solution is to run air ducting and a fan to the light hood and close it off from the circulation of the grow room but I Rating: 5