Building an igloo is fun, a lot of work and the results are sometimes surprising. We once built one in the Kachina Peaks Wilderness area as part of a training class. Another guy and I had to pack snow with our snowshoes, cut and place blocks, pack more show, cut more blocks, etc.
Using this method it took the two of us about 6 hours to make the igloo. The plan was to sleep in it and we did. However, it was about 20 degrees F overnight and it was so warm in the igloo that everything we had inside, such as sleeping bags were soaked. It was quite warm and wet in the igloo at those temperatures. We did show the technique and we did get an igloo, the conditions both snow quality and the temps were just not right for an igloo! It would have been near impossible to dry those sleeping bags if we would have been staing another night.
Keeping in mind that it would have taken less than 5 minutes to set up a 5 pound, 4-season tent...Still, igloo building is a good skill to know.
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No, I am not Bear Grylls, but I stayed at a Holiday Inn Express last night and Bear was there too!