In order to thermally insulate your tent you will need:
- 2 or more sturdy emergency blankets: "All Weather Emergency Blanket" available from sporting goods/camping stores. These "blankets" are insulating tarps and have nice grommets on them. They are NOT the cheap emergency mylar blankets! The mylar blankets crinkle and tear in the wind!
These blankets are 5' by 7' and should cost between $10 and $15
-- that's pricey, but they are well worth it!
- 6 or more clamps: You can get these clamps from your local hardware store. I found that two sizes were really handy: Small green clamps ($.37 at Home Depot) that can pinch one blanket around a tent pole. The larger red ones ($2 also at Home Depot) that can pinch 2-4 layers of blankets for where blankets will overlap.
How many blankets and clamps you'll need depends on the size of your tent. You can cover a small tent in 2 blankets and maybe 6 clamps. My large tent shown in the pictures will eventually have 4 blankets, 6 large clamps and 8 small clamps.
I would suggest that you make a guess as to how many clamps and blankets you need and then simply keep your store receipt so you can return any blankets/clamps that you don't end up using.