Unwanted energy transfers

• What type of heat loss do foam seals around windows and doors help to minimize?

  Heat loss by convection
• How do foam seals reduce heat loss by convection?

  They reduce air flow in and out of the building
• What are the features of a house that help to reduce heat loss by conduction?

  • Insulation in walls, roofs, and floors
  • Double or triple-glazed windows
  • Use of thermal mass materials
  • Sealing gaps and cracks
• Why is it important to reduce heat loss in buildings?

  To improve energy efficiency and reduce heating costs
• What’s the purpose of putting insulating foam in cavity walls?

  To minimise air convection currents
• What’s being described

  “the resistance that an object encounters when moving across a solid, or moving through a liquid”

  Friction
• What help reduce friction between 2 surfaces

  Lubricant
• Fast moving vehie like cars and planes have a streamlined shape to reduce friction from air resistance. This allows them to use less fuel
• Why does cavity wall insulation contain pockets of trapped air?

  Air is a good insulator