Glass can keep heat inside a building. A glass greenhouse lets in the Sun’s heat to help plants grow. Double glazing can help to keep a house warm. A layer of fiberglass padding can be put in the loft or attic of a house. It keeps the house warn in winter.
Some glass does not crack when heated.
The glass in this lantern is heat-resistant. You may have heat-resistant glass jugs, bowls or dishes in your kitchen. Ordinary glass cracks and breaks if boiling water is poured in or put over heat. Glass made with a special chemical does not break when heated. This is useful for glass cooking pots.
Mirrored windows help save energy.
Mirrored glass reflects a lot of the Sun’s rays and can stop buildings in hot countries from getting too hot. Double glazing and fiberglass are used to keep houses cool in hot weather and warm in cold weather.
A thermos flask keeps your drink hot or cold.
Glass is used inside a thermos flask. A drink is poured inside a glass container. The glass inside is covered with silver to stop warmth or coldness escaping. Another silver glass layer stops any coldness or warmth entering the thermos flask.
