My gow chamber was 1.3m square 0r about 4feet square i think.i hung a 1000watt lamp in that with no probs,and it was about 2m tall or about 6 1/2 feet .With a good quality vacume fan.
I also had a smaller propagation chamber with a 400 watt son-t light it was about the same width but only about 5 feet tall.
Happy growing...