RetroFoam™ for Hard to Treat Walls

According to the Energy Savings Trust, somewhere in the region of 6 million properties in the UK have cavity walls that are classed as ‘hard-to-treat’ meaning the same methodology or products cannot be used as those in a standard cavity wall.

A "hard to treat" cavity wall usually consists of one or more of the following:

• A narrow cavity less than 50mm wide
• A wall of prefabricated concrete construction with a cavity
• Metal frame construction with a cavity
• A stone cavity. Many older properties have uneven cavities in walls constructed of a natural stone outer leaf and a block or brick inner leaf
• A timber frame un-insulated studwork cavity.
• Cavities that have already been partially filled.
• The property is simply too high for standard cavity treatment i.e. it is more than four floors high

Exposed properties that are located on the sea front or on hillsides and subject to severe wind-driven rain may also classified as "hard to treat" as are properties with access difficulties i.e where two adjacent properties are close together may require insulation to be installed internally.

How RetroFoam™ Can Help

For insulating a hard-to-treat cavity the standard methodology is to drill holes and inject RetroFoam™ into the wall cavity as outlined below:-

1. The internal wall is checked for holes into the cavity. Any holes are filled to ensure there is no leakage into the property when the insulation is installed
2. Holes are drilled in a specific pattern and spray foam is injected in a staged process to ensure the whole cavity is filled from the bottom to the top
3. The contractor will often use a camera to ensure that the whole cavity is filled equally and that no gaps are left in the insulation
4. Upon completion, the installer will check all flues, vents, and pipes to ensure that all appliances are operating correctly and that nothing has been blocked by the new insulation
5. Finally, a mortar is used to fill the holes in the external brickwork