An igloo is a little dome-shaped house made of snow. It is used by Inuits in Canada and Greenland as temporary shelter while hunting. How could a snow house keep someone warm? The answer lies in snow’s effective insulating properties, which enable the inside of the igloo to remain relatively warm. The air pockets trapped in snow make snow a good insulator and it does not allow heat to pass through. The trick also lies in the way an igloo is built.
An igloo is built from compressed snow, sawed and made into blocks. Snow blocks are stacked spirally in layers placement of snow blocks gives the igloo its strength. A tunnel is dug out on the floor in front of the blocks after they are set. The entrance is at a right angle, which keeps the high winds from blowing straight into the igloo and chilling the residents. A vent, a small hole, is made through one of the snow blocks in the igloo wall.
The vent helps keep the interior of the igloo dry by allowing the water vapour that people breathe out to escape from inside. A sleeping platform is made of snow and is built up to 60 cm above the floor level. As warm air has a tendency to rise, the warmest part of the igloo is closet to the ceiling.
Even when the exterior temperature is -45 degrees C, the temperature on the inside could range from -7 to 16 degrees C, when warmed by body heat alone.
Picture Credit : Google