Twenty minutes sounds pretty fast. They’re usually longer to dig and always tedious.
I don’t know about specific techniques other than as big as necessary depending on the people in your party.
I’ll ask Steve to comment.
Apologies in advance if this is off topic for the site. I’m justifying it as free speed.
I’ve been experimenting a little with snow shelters (East Coast climber so access to snow is limited). It seems to meet that the torpedo tube snow cave Steve mentions in Beyond the Mountain is the way to go, as it requires the least snow removal. Steve mentions “getting good” at building these caves.
What does good look like? The bottom half of a slightly up-angled T slot cave? I’m assuming a rectangular tube is the easiest to construct with a snow saw. Something so narrow has to be a pain to move blocks from back wall to entrance though. What’s your ideal size?
A snow shelter seems like the way to go in terms of lightening the pack, but 2 hours survival shoveling snow at the end of the day seems counterproductive. Any tips to get me to a 20 min snow shelter is greatly appreciated!