This varies depending on the size of the property.
As a guide, typical costs are around £1140 for a detached bungalow, £820 for a mid-terraced house, £1400 for a semi and £2700 for a detached. Irrespective of the size of the property, you should be able to make back the installation cost in five years or less due to the savings you will make on your yearly energy bill.