Question about Sorel Caribou

I tried different sizes (my size, full size up) and at the end, I went up half a size from my normal size.

I normally wear a 39 - but had to order a size bigger - they are rather narrow at the front, I also find them really heavy in terms of weight - but they are great for winter, feet stay dry and warm - oh and you have to loosen the shoe laces well to take them off...