I mash in a cooler in the kitchen, then conduct the boil outside. I set up my burner on my back patio so I can watch it from inside. I'm brewing tomorrow morning with temps in the single digits. I don't think it really takes any longer to get a boil, but your boil-off rate will be a bit higher. I store my hoses in the basement and don't bring them outside to hook up to the chiller until I'm close to flame-out. Cooling definitely goes much faster in the winter!