Also, Alric, why are you making a tent out of wool rather than canvas? What's the benefits to that?
Several thoughts were behind it the first time I tried two years ago. First, cotton canvas wasn't around in 11th century England, so I'd have to go with wool or linen/hemp. Hemp canvas is really expensive, though, and I couldn't afford it (while wool was on sale for $6/yd). And I couldn't find linen in a heavy enough weight to keep the rain out (12oz). So I went with wool.
But I also suspected (correctly) that wool would drape differently from cotton - less taught, a little more saggy. And that was the look of the tents in the Utrecht Psalter, on which I based my tent. And my wool tent did have the right saggy look when it was finished, which doesn't mean that the original had to be made from wool, but
did mean that wool got me the look I was going for (in a way that cotton, which gets tighter instead of sagging when it's wet, didn't). Perhaps hemp canvas would have as well?
But the biggest selling points are more practical. Cotton mildews like crazy when it gets wet, and it's flammable. Wool doesn't mildew, and it's mildly flame resistant.
Interestingly, the tent doesn't seem to be noticeably warmer than cotton (kind of a bummer on those cold nights when you want to keep some heat in).
I mostly intend to keep using wool because of the cost (hemp canvas is still much more expensive, and I don't want to use not-period-for-Alric cotton) and the mildew resistance.
