So I've got a box at the moment, roughly 1x1x1m. Unfortunately I've got to move it out of the basement as I'm having some work done down there.

I've got a loft space that is insulated and setup for living in, but it's empty. I figured I'd put them up there for a bit but the box is too big to move as I built it in the basement. I'm not too keen on building something properly up there so I'm looking for something I can put up/take down easy. Literally thinking, put some hooks in the ceiling, hang light, put plants underneath and point desk fan at them.

I'm thinking it would be a much better place than the basement so thinking about long term now...

Unfortunately I can't put a hole in the wall for ventilation but it is quite a large area and i've got a couple of windows that I can lock in a partially open position.

With such a large area am I going to need a ridiculously large ruck/carbon filter? Would it even work in such a big space like that? What if I just have the ruck + filter close to the plants sucking in the air and pushing it away, without any sort of negative pressure would it be a complete waste of time? Like I say, only 4 plants with a 400w HPS.

what about an old large double wardrobe, 2x3x7ft would be ok for a 400w with a cf and 125 rvk outake and if poss 100 intake or passive vents
easy enough to convert, lots of info in the growroom design forum, here,
esp Church's thread.

grow tent?