The water won't be a problem.

You probably can get away with just venting the grow space out into the rest of the garage. You will have to check the temp when you have the lights up and running to be sure about heat. If it is cold where you are then it won't be a problem, you may have to heat the garage when lights are off.

Recirculating carbon filter would be your best bet.
Perp Reviewed by Perp on . Growing in a wet room? :jointsmile: A friend of mine is a few days from moving plants from his vegging area into his newly anointed flowering area, a free-standing "garage" where a bit of water acculuates on the floor when it rains. It's a 12 plant in 12 DIY 5 gallon bubble-bucket w/ drip rings and air pumps-type hydro setup. Local laws are such that he's allowed 12 plants, so he wants 12 big, high-yielding plants. He's got a 1000w Hortilux HPS and a 400W MH, with the intent or running both at the same time Rating: 5