Party wall project guide

Why is it important?

A party wall is a dividing partition between two adjoining buildings that is shared by the owners of each building. In an energy efficient build the wall should be insulated which will also help reduce noise transfer.

How is it installed?

To reduce the passage of sound through a party wall it should be built as a cavity wall construction consisting of two skins of aerated blocks fully filled with Knauf Earthwool Party Wall Slab which is designed to be an acoustic and thermal insulation.

To further reduce the transfer of heat from one dwelling to another it is recommended that below the DPC the cavity is fully filled with 100mm PIR insulation reducing thermal transfer.

Earthwool Masonry Party Wall Slabs have an A+ generic Green Guide rating and are Zero ODP and GWP rated products.

Hints & Tips

  • Ensure Masonry Party Wall Slab insulation batts are kept clean and dry during construction and any mortar that may fall on them is cleaned off.

  • Masonry Party Wall Slabs should be friction fitted between wall ties and all joints should be butted up with no gaps.

  • Ensure mortar snots are removed from the cavity side of the blockwork.

  • Ensure correct positioning and quantity of wall ties are incorporated within the wall construction.

  • Masonry Party Wall Slabs within the internal gable wall should always be taken up to ridge level to future proof the property for the possibility of the roof void being used as a habitable space.