Partial Fill Cavity Wall Insulation

Insulating partial fill cavity walls

Thermal Performance

The exterior walls of most homes have a space or cavity between exterior sheathing and interior drywall. Improvement to the thermal performance of this cavity can be achieved by the installation of Ballytherm wall insulation.

This wall insulation is resistant to moisture and is not affected by moisture that may occur with the cavity of the wall. The outer face of the inner leaf of the wall is where the boards need to be fitted. The insulation is supported on wall ties and held in place against the outer masonry or sheathing using enhanced wall ties fixings .

Boards of cavity wall insulation can come with a variety of edges, such as tongue, ship lapped, or butt. Installation will require the use of vertical joints that are staggered to create a layer that is continuous. Ballytherm insulation UK can also be purchased in many types of thicknesses to facilitate many installation combinations. Calculate the required thickness using Table 8.

Table 8

Further Advice & Information

For more information about Ballytherm products, technical advice, or guidance on the suitability of our products for your project, contact us at 0800 644 6900,, email us at or use our contact form.

Wall Insulation

Design Guidance