Reducing Unwanted Energy Transfers

• It can be done by either CONDUCTION or CONVECTION
• THERMAL CONDUCTIVITY = how quickly energy is transferred through a material by conduction.
• CONVECTION = warmer particles rise, cool particles sink.

CAVITY WALLS:

• Inner wall and outer wall with AIR GAP in middle
• Air gap reduces amount of energy transferred by CONDUCTION through the walls
• If the air gap is filled with FOAM, the energy transferred by CONVECTION is reduced.

LOFT INSULATION:

• Can reduce CONVECTION CURRENTS that are created in lofts

DOUBLE-GLAZED WINDOWS

• They work in the same way as cavity walls - they have an AIR GAP.
• This prevents energy transfer by CONDUCTION through the windows

DRAUGHT EXCLUDERS:

• When placed around doors and windows, they reduce energy by CONVECTION.