Cavity wall insulation
Information and FAQs
Cavity wall insulation is a method used to improve the energy efficiency of buildings by filling the gap (or "cavity") between the inner and outer walls of a property with insulating material - it is like putting a coat around your home to keep it warm and cosy. The cavity was originally intended to prevent moisture from penetrating indoors; however, it also allows heat to escape. Insulating this space helps to:
- Reduce heat loss
- Lower energy bills
- Improve comfort
- Reduce carbon footprint
Insulation is typically installed by drilling small holes in the outer wall and injecting insulating material into the cavity. The holes are then repaired and made to match the existing wall.
FAQs
- How long will it take to extract the cavity wall insulation and rubble
It can take one to two days to extract the cavity wall insulation.
- How long will I have to wait before the cavities will be refilled?
Following the removal of the old insulation and any rubble that maybe present, the cavities can be empty for up to two weeks. You will be provided with dates for the refill.
- How long will it take to refill the cavity wall with insulation?
It takes around half a day to install cavity wall insulation, depending on the size of your home. Cavity wall insulation can also be installed as part of wider energy efficiency upgrades, such as during a loft insulation installation.
- Will I need to be home when the work is being done?
Yes, you will need to be home during the extraction and refill stages of the works.
- What is a post extraction survey?
Following extraction, the holes in the external wall are covered to stop water entering, allowing the cavity to dry out if needed and any materials remaining to settle. A post extraction survey is completed a few days after to ensure all the material has been extracted. A small camera (borescope) is used to inspect the empty cavities. There is no need to be home during the post extraction survey, however, permission of unrestricted access to the property grounds are required. This survey usually takes one hour to complete.
- Will it be noisy?
Yes, some noise is expected during the works.
- I have vents/gaps, will the material come into my home?
The gaps and vents will be covered to prevent materials coming into your home.
- Will the drilled holes be filled upon completion?
Yes, the drill holes will be repaired following completion of the refill. The installer will use mortar to seal the hole which is matched up as close as possible to the existing walls of your home.