I have a 6m x 6m x 2.3m workshop, and this is definitely underpowered :-( it did heat the workshop by about 4-10 degrees celsius, which is great, but not confortable when it's minus outside. If you plan on burning anything other than diesel, like used oil with gasoline, etc, it will clog the machine eventually. I've bought an upgrade kit for the lines from aliexpress, it comes with the soft green ones.