. So when you build vents, whether it's for a grow room, or a whole building, theres a whole scientific theory behind whether the intake or the exhaust should be more powerful, vacuum and all that stuff. I seem to remember that the exhaust should be more powerful than the intake, can anyone confirm or refute please? I've googled like mad, but I just can't find any good answers and it's time to get building a proper space... I'd be really greateful for any help. Thanks! imp: .