Building a J Tube Rocket Mass Heater

This short video of still photographs documents the building of our Rocket Mass Heater in 2015, the changes we made to improve initial performance, and the maintenance (and changes) we carried out in 2019. Our first (partial) build in 2007 was easier as it was a workshop with a group of people which made it much more fun. This build was quite hard work for just the two of us (over 60’s), but not impossible and totally worth it. It’s a very efficient form of heating, much more efficient than the 12Kw traditional wood-burner it replaced. I don’t think I would ever willingly choose to live in Northern Europe without a rocket heater and I totally recommend it if you have the space. In 2021 we finally added the lime mortar coating. This video was produced as evidence for You can find more information, free resources, DVD’s to buy and experts generous with their knowledge to help you with your build, on the