Use of conductors and non-conductors:

In houses, good thermal insulation means lower consumption of fuel. For this, the following measures may be taken to save energy.

• Hot water tanks are insulated by plastic or foam lagging.
• Wall cavities are filled with plastic foam or wool.
• Ceiling of rooms is covered by insulating materials (false ceiling).
• Double glazed window panes are used. These window panes have air between glass sheets that provides good insulation.

Uses of a good conductor:

         Good conductors are used when the quick transfer of heat is required through a body. Thus cookers, cooking plates, boilers, radiators, condensers of refrigerators, etc. are made of metals such as aluminum or copper. Similarly, metal boxes are used for making ice, ice cream, etc.

Uses of Insulators or bad conductor:

                Insulators or bad conductors are used in home utensils such as handles of sauce pans, hot plates, spoons, etc. They are made up of wood or plastic. Air is one of the bad conductors or best insulators. That is why cavity walls i.e. two walls separated by an air space and double-glazed windows keep the houses warm in winter and cool in summer. Materials that trap air i.e. wool, felt, fur, feathers, polystyrenes, and fiberglass are also bad conductors. Some of these materials are used for laggings to insulate water pipes, hot water cylinders, ovens, refrigerators, walls, and roofs of houses. Woolen cloth is used to make warm winter clothes.

                Soft insulation boards are used between the external brick walls of a house.