CHAPTER 23 SYSTEMS AND SERVICES Draught insulation
Draughts are caused by cold air forcing its way into the house through vents or cracks around windows and doors. This lowers the temperature of the room and displaces warm air. Draught insulation is one of the cheapest and most efficient ways to save energy and money in a building, as it reduces heat loss.
Types of draught insulation
• Doors: draught excluders can be fitted around a door frame and to the threshold (space underneath). Types of draught excluders suitable for doors include:
o polyurethane-foam strips for the openings around doors
o brush excluders or fabric snakes for the base of doors.
Polyurethane-foam strips
• Windows: types of draught excluders suitable for windows include: o polyurethane-foam strips for openings o silicone sealants between the frame and the wall.
• Letterboxes: brush excluders can be used to keep draughts from coming through letterboxes.
Underlying principle of draught proofing In homes, 15% of heat is lost through the windows and 10% is lost through doors due to cold air entering through cracks and openings. Draught excluders block the entry of cold air, helping to keep the warmer air inside and an overall even temperature.
?
(i) State, giving a reason, the two areas of this house that should be prioritised for insulation. (12) OL
(ii) Name and describe the method of insulation you would recommend for each of the following:
• attic/roof • walls. (16) OL Did you know
As part of the 2008 building regulations, every new home must carry out an air tightness test to determine the level of uncontrolled air flow through gaps or cracks in the fabric of a building. The results of the test highlight areas of the home that will require further insulation or draught-proofing.
Identify three areas of the house that should be insulated in order to reduce heat loss. Recommend a method of insulation for each area and explain the underlying principle of each method. (24) HL
