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A thermogram shows the distribution of heat over the surface of a house. It highlights where heat is being lost.
Keywords:
walls 36%
floor 28%
roof 20%
windows 12%
doors 4%
Keywords:
U-Values
A measure of how well a building component, e.g. a wall, roof or a window, keeps heat inside a building.
The higher the U-value the more heat flows through so a good U-value is a low one as you want to keep heat inside the building or outside depending on the climate you live in.
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Find out the U-Value for the following and work out what is the best combination to reduce your household energy bills.
Outer wall – 9” brickOuter wall – 11” block brick with cavity insulation
Solid concrete floorTimber floor
Flat 50mm insulated roofPitched with felt, 50mm insulation Pitched with felt, 100mm insulation
Wooden window frame, single glazedUPVC window frame, double glazedWooden window frame, double glazed (Low E)
http://www.diydata.com
http://www.self-build.co.uk
Keywords:
Find out the U-Value for the following and work out what is the best combination to reduce your household energy bills.
Outer wall – 9” brick (2.2)Outer wall – 11” block brick with cavity insulation (0.6)
Solid concrete floor (0.8)Timber floor (0.7)
Flat 50mm insulated roof (0.7)Pitched with felt, 50mm insulation (0.6)Pitched with felt, 100mm insulation (0.3)
Wooden window frame, single glazed (5.0)UPVC window frame, double glazed (2.9)Wooden window frame, double glazed (Low E) (1.7)
http://www.diydata.com
A lot of heat energy can be lost through windows.
Double glazing adds an extra pane of glass. The air trapped between the two panes acts as an insulator and reduces heat loss by:
side-view
of double glazing
insulating layer
of air
Keywords:
Conduction
Method Conduction
Convection
Radiation Cost
Double Glazing
YES NO NO HIGH
A lot of heat energy can be lost through windows.
Double glazing adds an extra pane of glass. A vacuum can be created between the two panes to reduce heat loss by:
side-view
of double glazing
insulating layer
of air
Keywords:
Conduction and ConvectionAs there are NO particles
Method Conduction
Convection
Radiation Cost
Vacuum Glazing
YES YES NO HIGH
The air trapped in the cavity acts as an insulator and reduces any heat loss due to: _____________
Most outside walls have an empty space between the two layers of bricks called a cavity. convection
currents in the cavity
Keywords:
Conduction
Plastic foam insulation can be pumped into the cavity to prevent ________
foam insulationprevents
convection currents
Keywords:
Conduction and Convection
Method Conduction
Convection
Radiation Cost
Cavity Insulation
YES YES NO HIGH
The air warmed by radiators (and other heaters) is carried around a house by convection currents.
heat loss
loft insulation
The house becomes heated but, if there is no roof insulation, the warm air continues to rise.
The heat eventually escapes through the roof tiles by ______________.
Keywords:
Conduction
Method Conduction
Convection
Radiation Cost
Loft Insulation
YES YES NO HIGH
Heat loss from a radiator can be reduced by
A radiator produces infrared radiation.
Some of this heat energy is absorbed by the wall that the radiator is attached to, and so the wall heats up.
The foil prevents heat radiation from reaching the wall by reflecting it back into the room.
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Placing a shiny sheet behind the radiator
Method Conduction
Convection
Radiation Cost
Radiator Panels
NO NO YES LOW
Draught excluders are hairy or spongy strips that can be used to close the gaps around doors and windows.
A draught is the movement of air due to __________
A lot of heat energy can be lost from a house due to draughts escaping through gaps under doors and around windows.
Keywords:
Convection
Method Conduction
Convection
Radiation Cost
Draft Excluders
No YES NO Low
A draught is the movement of air due
Warm air rises and is carried up towards the windows in a house by convection currents.
Fitting curtains and closing them can prevent draughts leaving a house and so reduce heat loss.
This heat energy can escape through gaps around windows that are uncovered.
In addition, curtains are opaque and so radiated heat does not pass through them.
Keywords:
Convection
Method Conduction
Convection
Radiation Cost
Curtains NO YES YES LOW
Keywords:
Keywords:
Keywords:
walls 36%
floor 28%
roof 20%
windows 12%
doors 4%
Keywords:
Heat lost from Percentage
Roof 20
Windows 12
Doors 4
Walls 36
Floor 28
Keywords:
Heat lost from Percentage
Roof 20
Windows 12
Doors 4
Walls 36
Floor 28
20 + 12 + 4 +36 + 28 = 100
20% Roof
12% Windows
4% Doors
28% F
loor
36% W
alls
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