Ok, I am a little nervous about this one. I am taking my troop of scouts “Snow Caving”. I have read up on the subject and build one in the backyard over the Christmas holiday. But still want to know more so I am coming to the experts.

Any suggestions?

During my 2 years as a Marine Mountain Warfare Instructor in the Sierra Nevadas, I probably spent a couple months in snow caves. I'm sure the reading you've done provides the most important steps, but here are a few of my observations:

1. Ventilation is obviously important. We used a ski pole shoved through the ceiling for our hole. We always left the pole in the hole, so we could jiggle it around every once in a while to remove new snow and keep the hole open.

2. Dig a deep "cold hole" at the entrance to keep it a little warmer inside.

3. Leave plenty of distance between your sleeping shelf and the ceiling. The warmth of your breath and body heat will sometimes cause the ceiling to sag down. I woke up one morning with the ceiling on my chest and the only way I could get out was to stand up through the roof in my sleeping bag. Luckily there was no new snow, or I might have been stuck.

4. Make sure the ceiling is rounded perfectly or the condensation from your breath will drip down and soak you and all your gear. We used a steel canteen cup to sculpt the ceiling and to dig shelves to place gear/snow turnips (condoms filled with urine while in the sleeping bag and left on a shelf to freeze).

5. I'm not sure where you are from, but avalanche prone areas are an obvious concern.

Hope this helps.

George

When I was in High school (many years ago) we went Winter camping on a few occasions, this is what we did.
Find a drifted embankment, barring that, pile up snow about 5 ft high.
Dig into it, leaving about a foot thickness in the walls and roof.
Heat/light it with a candle, making sure to allow for a draft/airflow.
This may not sound as involved as some might like, but I and my friends spent many nights a couple of miles from the house in just such shelters.