First of all, the house should be warm. The raw material of igloo is ice (snow), and the temperature is below zero. How does it keep warm? Secondly, the ice and snow are melted by heat, and the people who stay in the igloo are natural stoves. How can we ensure that the inner wall of the igloo does not melt? So even on the surface, the existence of igloo is strange enough, even puzzling.
Inuit magical igloo, made of pure "ice", has surprisingly good insulation effect.
The BBC once made a detailed documentary about the Inuit igloo. This group of people living in the Arctic Circle has a peculiar architectural model, that is, using local materials and directly using the cheapest local ice and snow as building materials to build igloos.
They make ice and snow into bricks, and then use these bricks to build houses. With the skillful hands of local architects, it won't take long to build an igloo with a white and bright appearance and a Disney fairy tale world inside. It looks a bit like a Mongolian yurt on the Mongolian prairie, with a round top and a round bottom. An igloo is equivalent to a room.
Strangely, although it is made of pure ice, it is not very cold inside the igloo, at least it is much higher than the temperature of MINUS tens of degrees outside. Even from above, we can see a burst of "white smoke" from the pores of the igloo, indicating that the temperature difference between inside and outside is really great, so that the water vapor in the house condenses as soon as it comes out. Of course, this can also directly reflect the powerful thermal insulation ability of the igloo.
The unique structure makes the igloo not only warm but also not afraid of melting.
Man is a warm-blooded animal. If the igloo wants to live in man, it must constantly accept the heat of the human body. The freezing point of water is zero degrees Celsius, while human body temperature is between 36 and 37 degrees Celsius. There is a temperature difference of nearly 40 degrees between them. So if the inner wall of the igloo constantly receives the heat from the human body, it will melt into water. At that time, even if the igloo does not collapse, it will be packed. How can people live in it?
But in fact, igloos can not only live in people, but also are not damp inside, but are like ordinary houses. How is this achieved? Actually, it has something to do with its unique structure. Someone once said that the igloo is a great project, and it is impossible to build it without superb technology. On the other hand, Inuit people have mastered this craft for generations, so igloos have been preserved as their unique culture.
Three special technologies are the important reasons to keep the igloo from melting and keeping warm.
The key factor why the igloo can exist as a living room is that it used three special technologies when it was built.
The first one is an inclined spiral ice wall. In normal wall building, bricks are laid horizontally and vertically, and the middle is bonded with adhesive (usually cement mortar). However, the igloo is not like this. When the builder built it, he deliberately piled the ice bricks a little obliquely, showing a spiral upward trend. The advantage of this is to ensure that the airflow spirals upward, effectively disperse the excess hot air in the house, and prevent the hot air from accumulating on the surface of the ice wall and causing the ice wall to melt.
The second main process is to preserve the airway. There is an air outlet at the top of each igloo, which uses the principle that hot air rises and cold air sinks to discharge excess hot air in the house. Therefore, you can often see that there is a "white smoke" above this blowhole, which is exactly what it is radiating.
The third process is a special bonding method. When building a house with ordinary bricks, cement mortar will be used as an adhesive, and the walls will become firm by using the hydraulic properties of cement. But the igloo can't use cement, so how are its "bricks" bonded?
It's actually simpler. As long as the edge of each ice brick is slightly melted and then solidified, it can be naturally glued, and it is stronger than ordinary bricks glued with cement mortar, because all ice bricks are glued into a whole.
As for how to make the edge of each ice brick just melt slightly, it is necessary to use a local specialty-seal oil. Just ignite seal oil in the newly-built igloo, and use the heat released by combustion to properly bond the ice wall into a whole.
As long as these skills are mastered, it is very convenient to build igloos without spending too much manpower. Experienced local craftsmen can build an igloo in one day with only two people. As for the building materials, they are all made of local ice and snow, and of course they are not expensive.
However, although the unique structure of igloo ensures that it is not easy to melt, this kind of house is still not as good as a permanent building, so Inuit people will continue to build new igloos, and abandoned igloos do not have to worry about polluting the environment at all. After all, they are taken from and part of the environment.