my basement is 11'12 x 12'9 and 5'9 feet tall plus the area of the steps down to it. my humidity stays around 50 to 60 when lights are on but reach up to 90 when off. i have one moldy bud so far. there a cemented out square in the ground that all the water seeps into, got to cover that up to, its got a sub pump so it doesn't over fill. any who, just looking to get the most bang for my buck.......