Here's an approach such that, even if it doesn't work for others, may prompt some other idea which does:
Below is a pic showing how I and a friend did our last brew, about 10 days ago. Outside temps were about 30. I could brew in the garage w/ the two garage doors open, but that's COLD. Such cold temps also make it harder to maintain temps in my mash tun, and makes reaching and maintaining a boil harder to do. And I won't allow over a gallon of moisture to collect on the inside walls and in the garage ceiling insulatoin.
So the plan was to find a way to exhaust steam from the boil kettle through a window to the outside, keep the garage doors closed, and crack the service door to the garage just a bit to provide makeup air.
We also had a propane heater going in the garage which effectively heated the incoming makeup air and made the environment comfortable enough that long-sleeved shirts were sufficient.
Much like the hood over a stove, our arrangement below captures an air stream which pulls the steam outside. The extra sheet goods on top were necessary to stop the rise of the steam and allow the airflow to capture it and direct it outside.
It worked like a charm. In fact, so much so that it even crossed my mind to try it this weekend when temps on Sunday will be a high of -6. Nah, can't do that--that steam would freeze as it left the house. Too darned cold, but I'm sure this would be effective down to 20 degrees or even less.
Now--how could one do this if one doesn't have a garage? Perhaps a popup tent might suffice, or a sort of lean-to against the house or apartment, or...?
Anyway, food for thought.
