The loft is pretty much pitch black, it's secure, lights can be hung from the beams, fans can benefit the already fairly good air flow.. would a specialist grow tent from a hyrdro shop be worth its cost?
I mean, if I rig up a 600w bulb and ballast on a timer, a couple of oscillating fans also on timers, and obviously give the (1 or 2 max) plants the time, care and attention they need; do I really need the enclosed, vented, filtered, mylar coated, several hundred £/$ grow tent as well?
The reason people get tents is it much easier to get the environment you need. Sure you can grow in a loft, I've had some great experience in the past doing that, but it is much harder to keep your temperatures and humidity consistent and thus the plants didn't yield as well as I now know they could. Heating a loft when you need to can get pretty expensive.
I've got a friend who's a carpenter, could I get him to make a cabinet from wood? and line it with the reflective emergency blankets, and use fitted fans to remove air (heat)?
what sort of space and fan would you need for a 600w (MH/HPS) bulb?
stick with a tent, as the guy above said, emergency move and been able to control the airflow going through your tent, plus I would of thought that the wood wouldn't displace heat as good as the tents