[igloos] how to build 'em

With that time of year almost upon us, you'll clearly be wondering how to construct your igloo. How Stuff Works explains:

1. Find an area with a lot of dry, hard-packed snow. Use the snow saw or knife to cut large blocks -- the harder the snow is, the more solid the snow blocks will be. Your snow blocks should be about 3 feet long, 15 inches high and 8 inches deep, according to "The Complete Wilderness Training Guide."

2. Smooth the edges of the blocks. Place them in a circle, working your way up. Blocks should decrease in size as you work upwards. Using your shovel or saw, cut a hole under the wall to create the igloo's entrance.

3. Overlap the blocks and shape them to lean inward, creating the dome. The blocks should support each other in order to prevent the dome from collapsing. If necessary, use a stick or other support in the interior to support the blocks at the top until the dome is finished.

4. Once all the blocks except the last one have been placed, find a block that is slightly too large for the last opening on top. Place it on top of the igloo and wiggle it into place, shaping as needed. It should be shaped to fit exactly in the opening.

5. Shovel loose snow onto the igloo. Pack it into all of the crevices. Smooth the inside of the igloo by hand and shovel out any extra snow.

6. Finish the entrance by digging a hole in the shape of the desired entrance (some igloo aficionados prefer L-shaped entrances because they keep the wind out better). Then cover the hole with snow blocks.

7. You must cut ventilation holes in the walls and roof to prevent suffocation. Air holes also prevent body heat from causing dangerous levels of carbon dioxide.

8. If you want to upgrade your igloo, consider adding these amenities:

* A small stove: Yes, you can cook inside an igloo. Excessive use of a stove can build up carbon monoxide to dangerous levels, but your air holes should guard against that.

* Extra head room: Some igloo builders recommend digging the floor down a little to allow for more space.

* A sleeping platform: You can loft your bed with some extra blocks of snow. Since warm air rises, you'll enjoy a little extra heat that way.

There is a nice pictorial version here too.