Hey guys Iam new to the forum and very new to growing. I have been researching for weeks now but still having problems finding anyone to relate to. So I have a farm up here in Alberta, recently got my card and have decided to start growing on my own. I have a 10x16 garden shed in my yard that I built a separate 10x6 room in the back that is fully insulated and sealed up that houses the water filtration system for my house since I have no basement. I have painted the whole inside flat white and built a stand to hold my plants, I also just ordered a 600w hps light. Now it consistently gets down to -20 Celsius or colder all winter long here with snow on and off. I have the room heated so that my water system doesn't freeze, just with a ceramic mounted wall heater, it keeps it around 75 degrees in there and humidity is 40-60. My concerns are with ventilation, I know I need to be replacing the air in the room every 5-10 min and Iam unsure how to achieve this while keeping proper temp and humidity in there if Iam sucking in freezing cold air, I can take my intake air front the other room in the shed but is still cold. It's the perfect little room being that I have power and water in there already, I want to start with 4 plants then eventually set up two or three stations in there to have planets at all stages. Any advice would be very appreciated. I have been researching for weeks and have yet to find anyone to really compare to for advice or anything that's why Ian searching out now!