Loft Insulation
It is important that your loft is insulated because otherwise you couild loose a lot of money. Without the insulation in the roof all the heat will be able to ascape out of the roof which would mean your house would be cold.

How does loft insulation keep heat in the house?
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Heat will always flow from a warm area to a cold one. The colder it is outside, the faster heat from your home will escape into the air outside.
Insulation makes it much harder for heat to pass from your roof to the air outside by a layer of material which has lots of air pockets in it. These pockets trap heat. This stops the air from leaving the house and going outside.

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Did you know?

If every one in the UK installed 270mm thick insulation, we could kinetic energysave around £259 million and nearly
300 milliomn tons of CO2 a year.

Conduction, convection and radiation
When the loft
When the loft insulation has air in the pockets it means it isn't very good at conducting. This is because air is a poor at conductor of heat because air is a gas and the particles in a gas aren't packed closely together they move around freely. In the pockets of air the particles are less likely to colide transfering kinetic heat energy. This means air is a bad conductor of heat.