My darkroom is in a very cold part of my basement. In the winter months, the temperature can go so low that Dektol doesn't work. It is walled off from the rest of the basement, which is normal temperature because, like the rest of the house, it is heated by forced air from an oil furnace. I want to insulate the darkroom and install a heating vent. I should add that I have ventilation now, just no heat. There is a darkroom fan to take out fumes and a darkroom vent in the wall so that the fan will draw air properly. I can tell that some dust gets in via the vent but so far, it is not a huge problem. Most of it winds up on the vent, which I wipe off regularly. However, forced air is notorious for dust. Have any of you solved this problem? What kind of vent, filter, etc., do you use to keep the dust out? I have also thought of insulating the room and then using an electric heater.