The igloo is a snowhouse that was used by the Inuit as a temporary shelter on extended winter hunting trips, but not as a permanent home. An igloo can be built in about twenty to thirty minutes - depending on the quality of the snow and the skill of the builder.

Blocks of snow are cut from snow banks using a snow knife and are arranged in the shape of a dome - not row upon row, but rather in a single spiral. Joints are filled in with snow and a hole is cut for ventilation.

The best snow comes from a snowbank formed by a single snowstorm. Blocks taken from snowbanks formed over a series of storms tended to break easily because of the layers within the snow.

Snow knives, used to both cut and trim blocks of snow, were made of bone or ivory and often had a slight curve to the blade. Following the introduction of metal to the Arctic by Europeans, the Inuit began making snow knives with single-edged steel blades.

Snow is a good insulator. 10 inches / 25 cm of fresh uncompacted snow can insulate about as well as a 6 inch / 15 cm layer of fiberglass insulation, making it a very good material for building a shelter.