Cavity Wall Insulation Extraction – A Case Study

More and more consumers are getting in touch with us about cavity wall insulation – you would of thought that the majority would be looking to install the cavity wall insulation bearing in mind we are an energy saving blog, however interestingly it is the exact opposite – they are getting in touch with us to see if we can help remove incorrectly / badly installed cavity wall insulation and then make good the walls – this does in some case include re-injection of the insulation if the product initially used was unsuitable for whatever reason. If you are interested in getting our help to remove cavity wall insulation then please simply fill in the form at the bottom of this page.

The cost of the works is approximately £21-22 per m2 and the process itself is relatively simple, although it does take a bit of time to remove safely. We have a highly qualified team of technicians out on the road now who are helping homeowners remove unwanted cavity wall insulation so we can definitely help!

Why do people want to extract cavity wall insulation?

We have gone into this in quite a bit of detail previously and you can read more about his here, but basically there are seven main reasons.

  1. It was installed a long time ago a – so no longer effective (foam)
  2. The house was not appropriate for cavity wall insulation (or at least the materials used at the time) e.g. if it was located on the coast
  3. The new homeowners are allergic to the insulation
  4. It is causing damp which is then transferring water across the cavity to the inner leaf
  5. There are voids within the insulation (causing cold bridging)
  6. Poor condition of the out brick work or raked joints
  7. Timber frame or steel frame buildings.

How do you remove cavity wall insulation?

Removing cavity wall insulation depends on the material within the walls. If it is wool insulation we can simply extract it out with what essentially is a giant hoover (although made specifically for this task!). If it is solid insulation, it is more fiddly because we need to break up the insulation so it crumbles and can be removed safely. This is carried out using high pressure air blown within the cavity through injection holes via a compressor.

Does the removal process damage the walls?

No – in fact, when we clean the cavity we also remove pre-existing rocks and mortar that the builders had dropped down the cavity when it was being built – so the cavity is in better shape than before it was ever insulated.

Can cavity wall insulation be removed from any property?

We have helped 1000’s of people remove the cavity wall insulation from their homes having previously had it incorrectly installed. We are yet to encounter a property where we have been unable to remove the existing cavity wall insulation – this includes a tower block!

How long will it take to remove the insulation?

This is a little bit like asking how long is a piece of string – it depends entirely on the building in question – prices range between £16 – 21 per m2 (subject to the survey and site conditions). First though we carry out a technical survey which will include prices, the plan of attack and a rough timeline.

A Cavity Wall Insulation Extraction Case Study – Mersea Island

For this job we worked with Gary at Extract survey (in house consultant)  and C&R Insulations Solutions. The block of flats was situated in Colchester on Mersea Island and the tenants were keen to remove the existing insulation because the insulating material had broken down and there was also evidence of water ingress in some of the properties.

The Cavity Wall Insulation Removal process

The first part of the process was the removal of a number of external bricks along the bottom of the affected wall to allow the material to be extracted. The technicians then drilled a series of 22mm holes over the affected area to allow high-pressured air to be blown into the cavity, which allowed the material to move freely. The defective insulation was then vacuumed from the cavity using our specialist machinery. Once the insulation was removed, a full cavity scrape below DPC was undertaken to remove all rubble. Once the full extraction was completed, the cavity was then scoped thoroughly to ensure all contaminated or damaged insulation was cleared from the cavity area.

Removal of cavity wall insulation removal

The project took 3 weeks due to its size – it was approximately 700m2 of which 90% required the existing cavity wall insulation to be removed.

    • Postcode of project – CO58DE
    • Existing Insulation – Bonded Urea Formaldehyde Insulation
    • Removal Time Frame – 3 weeks
    • Area of removal – 600 – 650m2
    • Cost – c£13,000.00

    If you would like to read more about cavity wall insulation, see our full guide here.

If you would like to get a quote for cavity wall insulation extraction please fill in the form below:

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