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  • Quick to install
  • May have been overlooked in earlier insulation work

What is it? 

Sometimes it can be worthwhile insulating the wall between you and your neighbour, depending on how your house was built.

If you live in a terraced or semi-detached house, then you will share at least one wall with a neighbour. This is known as a party wall. 

If your house has cavity walls, then your party wall may also have a cavity. Sometimes these cavities are sealed, and so air doesn’t circulate through them. But if your party wall cavity is vented to the outside air, then cold air will flow up through the cavity taking heat from all the adjacent rooms and sucking it up into the loft. 

This is called a vented cavity party wall and, if you have one, it could be worth insulating the cavity to stop cold air from circulating and stop this heat being wasted. 
Cavity party walls can be insulated in much the same way as all your other cavity walls. A specialist company will come and drill holes in your walls, and inject mineral wool, polystyrene beads or other material into the cavity. 

Is it right for me?

Party wall insulation is worth considering if you have a vented cavity party wall. The best indication is the age of your property.

If your house was built between 1950 and 2002 then there is a reasonable chance that the party wall is a cavity wall, and that the cavity is vented to the outside. 
If you have a solid party wall, or a cavity that is not vented, then there is little point in insulating the wall as the property next door will often be heated to a similar level, and will act as an insulating layer even if it isn’t heated at all. 

 Not all houses built between 1950 and 2002 have vented cavity party walls. 
Houses built between 1965 and 2002 are most likely to have a vented cavity, but you cannot be certain just from the age of the property. You will need a cavity insulation company to carry out a survey to check if your property would benefit from party wall insulation. 

How to get it

You will need a specialist cavity wall insulation company to insulate your party wall.