About Igloo Houses

Construction

• Igloos are built in fields of hard, packed snow. They're made of snow blocks cut from snow well beneath the soft, dry layers on the ground surface. Igloos shouldn't be more than 10 feet in diameter; otherwise you need a perfect dome for structural integrity and heat retention. Large blocks are cut to construct the bottom of the igloo, and smaller ones make up the top. Bricks are layered in a spiral pattern along the igloo's perimeter, placed at a slight slant to create a dome. The blocks support one another so they don't fall in. Blocks are smoothed together, and piled up snow is removed from the dome as it's being built. A hole is dug at the entrance, and blocks are piled over it, forming a tunnel entrance. The inside of the dome is smoothed well using gloved hands so moisture drips down its sides instead of from the roof.

Interior

• Traditional igloo houses have beds made from snow covered in twigs and animal skins. Modern igloos may have the floor covered with camping mattresses. The tenant may cut a niche in the inside to place a candle, cookware or supplies. Entrances are kept open for ventilation purposes, but animal skins or blankets may be placed as a door flap to keep warmth in.

Retaining Heat

• Despite being made from ice, a properly-built igloo house is actually warm. A deep hole dug at the house's entrance acts as a cold sink, trapping cold air from outside to keep the main living area warm. A ventilation hole near the top of the dorm is especially important if its tenants will cook inside it. The moisture created from cooking in the igloo flows down the dome sides, freezing overnight and reinforcing the igloo.

Considerations

• Igloo houses vary in size and construction. Igloos used for just one night may be round or oval. Igloos that need to last much longer must be as round as possible, and careful attention must be paid to block placement, with an extra wall of snow blocks must be built around the outside of the igloo. Snow is packed between the wall and igloo exterior to better retain heat. Igloos can be built in terrible weather conditions, including blizzards. Once the first blocks have been placed to form its base -- called the avallutaa in Inuit -- and the second layer of blocks is laid, you have a windbreak and can install the bricks from inside the structure.