I am setting up an attic grow room that is 90 120 x 120 cm. The space is like a triangle. I am using a dual 100 cm fluorescent. What can I do to prevent humidity building up? I already have a fan. Should I finish the walls if the insulation does not show? Do I add Mylar and paint? How should I train plants to grow to increase yield and use all available space.
You have a fan, is it a circulation fan or ventilation fan? Set up a vent fan to extract air from the small triangular space. You must have good ventilation. If the ceiling is not insulated, make it so. Adequate insulation keeps temperature fluctuations to a minimum. Do not use Styrofoam because it is flammable and you do not have much space for heat dissipation. Flat white paint will be adequate for your application. When plants are about two months old, they will need more light. Now they receive only 80w of fluorescent light from the dual fixture. Add a couple of 65w compact f1uorescents (CFLs) to grow respectable buds. Set up a horizontal trellis and train plants to an even profile so they receive more light. Fluorescent bulbs should be located about 2 inches from the canopy of the garden and will provide the minimum of light necessary for photosynthesis.