Q1.
Is it possible to construct houses that are not affected much by the outside heat and cold?
Answer
Yes, it is. Houses built in places with a very hot or a very cold climate use the idea of heat transfer to stay cool or warm — mainly by putting a poor conductor of heat between the inside and the outside.
- Hollow bricks in the outer walls: the air trapped inside the hollow space is a poor conductor, so it keeps the house warm in winter and cool in summer.
- Double wooden walls filled with cow dung and mud, as in the Mori block of Uttarkashi, Uttarakhand. Wood and mud are poor conductors, so they prevent heat loss and keep the house warm through heavy snowfall.
- Thick mud walls and thatched roofs in hot, dry parts of India, and light-coloured outer walls that reflect the Sun's heat.
Why it works: heat always flows from the hotter side to the colder side. If the wall between them is a poor conductor, that flow is slowed down almost to a stop — heat cannot get in during summer and cannot escape during winter.