Mittens for two hands

I want to make mittens that are very warm, but yet stretchable/big enough for two hands. I’m not asking for a specific pattern per se, just wondering about yarn and lining stuff.
Can mittens be warm and stretchable at the same time? If so, what yarn to use? What about lining - perhaps you could put it on one side only, as it will be unstretchable? If stretchable is impossible, any ideas about how to design big mittens that can be used without a second hand? Too big mittens is uncomfortable, but you shouldn’t rely on a second hand to be able to use them.

The story is that my boyfriend and I like to hold hands when taking walks, but now with Swedish winter and temperatures down to -10~-20 C (that’s 14~-4 F for you Fahrenheiters), you have to wear thick gloves and that kinda takes the feeling away a bit, you know?

During autumn, his gloves were quite stretchable so I could stick my hand into them, but his new mittens are not. The main problem is the lining, as it doesn’t stretch at all, and therefore limits the circumference of the opening. The actual gloves seem to be made of yarn that doesn’t seem very stretch-friendly either.

I would consider myself fairly experienced as a knitter, but I’ve only knitted mittens once before, and nothing for winter use. Is it possible to knit something stretchable yet warm? It seems like a contradiction to me. Of course I’d really prefer stretchable to naturally big mittens, because then he can always wear them. :cool:

There’s a pattern for that! It’s ‘Smittens’, or Lover’s mittens. Actually, there seem to be a couple of them - some have one large mitt and two to wear on the other hands.
http://www.cocoknits.com/knit/garments/accessories/smitten.html
http://www.gallentine.org/Knitting/loversmitten.html


I made some of these for my son and his wife. I used alpaca since it’s so warm.