Our tent is over 25 years old and used every single year and never had a tarp and has zero burns holes. Not a single hole anywhere on it. It has plenty of small black soot marks that it has picked up over the years but it has never been treated and has never leaked a drop inside. I could see a tarp keeping the tent warmer but we run a Kwik Kamp stove and it will usually blow you out of our 15x22. Would be nice for keeping it looking like new for the next 40 years but the usual demise of canvas tents is mildew which leads to canvas rot.