I built a rocket mass heater on my porch and then enclosed the porch around the heater to trap the heat and direct it into the house. The vinyl sheets and glass walls act like a greenhouse and the sun heats the house for free. I also gather my neighborhood brush collection and use it as free firewood. Free heat all winter long!!!!! The Sauna is an added bonus. Some folks have asked me about the mag drill I used. If you want more detailed reviews on tools I use in my videos check out my website. SuburbanBiology.com Here is a link to that drill on Amazon: https://amzn.to/3IVHogk As an Amazon Associate I earn from qualifying purchases. Merch store here: null Patreon link here: https://www.patreon.com/suburbanbiology Please consider becoming a youtube member of my channel. If you have read this far into the description here it is likely you would enjoy the perks of being a member. All you have to do is click the "Join" button right under the video. Thanks!