Removing Cavity Wall Insulation Q+A

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Removing Cavity Wall Insulation Q+A
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Q Reusing cavity wall insulation extracted from cavity walls

We are also extracting cavity wall insulation (and refilling with EPS bead) – a recent chat with another installer left us thinking about the extracted material (typically it’s what the industry calls foam insulation) and how it can be re-used for loose fill loft insulation.
There is potential for extracting this insulation and re-using it to insulate the loft at the same property.

A Reusing cavity wall insulation extracted from cavity walls

Question: What materials is being extracted, Answer: Foam insulation
- Does it contain ozone depleting chemicals as foaming agent gases
  - Is it a hazardous waste that needs to be captured along with all the released gases?
  - How much ODP gas has already been released?
- GBE anticipated a second wave of Ozone Depletion Potential due to pre and post 1980’s ODP use in thermal insulation until their use was outlawed in EU.
  - Specifiers and developers preoccupied with thin construction persisted in specifying ODP gases up to the last minute.
  - Demolition of these buildings will release ODP gases
  - Extracting their insulation will release ODP gases
- Question: Why is it being extracted?
  - Is its ODP safer where it is?
- Is it causing damp penetration?
  - This may be due to patchy, inconsistent or intermittent installation
- Is it Urea Formaldehyde based?
  - This was seen as a health problem due to off-gassing
  - After a long time installed is that still an issue? I do not know.
- Wanted to improve the performance of the cavity wall insulation
  - Whey then replace it with MOR Middle of the Road performance EPS Expanded Polystyrene
  - It is after all another Foam insulation material, but in bead format
  - Bead format leaves interstices between the beads,
    - a route for free flowing air with heat and moisture
    - a space for eddy currents to establish themselves
  - Can the density of the installation be increased to squeeze, flatten and close the interstices?
  - If you squeeze them this much is the insulation performance of the bead diminished?
- Question: How easy is it to comprehensively remove a set injected foam insulation
  - Vacuum is not enough
  - There has to be an element of mechanical disintegration
    - Releasing ODP?
  - From every nook and cranny (jargon for all the remote corners)
  - All the materials fortuitously attached, by mechanical key to textured surface or bonded to the surfaces of the cavity
  - What level of inspection is applied, that the work has been done well enough/at all?
- Question: Is the extract arising’s a waste or a resource?
  - Extracted materials would be classed as a waste
  - Does it contain ozone depleting chemicals as foaming agent gases
    - Is it a hazardous waste that needs to be captured along with all the gases?
  - Handling it may require a special license
  - Moving it from the site may require a special license
    - A hazardous waste license?
    - An ODP waste license?
  - Keeping it on site and reusing it may not need a special license
    - Fortuitous Serendipitous idea if it’s a good one
    - Using the material is one thing
      - Are you happy using a hazardous material (read Deleterious) in a building occupied by humans?
    - But the ODP gasses remain a major problem
  - Question: Do you have to provide any form of guarantee/certificate for the attic insulation?
    - Reclaimed materials could be available with a Product Passport
      - Your supply chain would need to establish the process
      - It should identify the materials and its properties
        
        It was considered inadequate for exiting cavity
      - Confirm it is uncontaminated
        
        Needs clean storage vessels
        
        May need ODP capture and special disposal
      - Confirm it is in good condition
        
        But you just smashed it up to get it out
      - Recycled materials will not be available with certification for installation
        
        The original manufacturer
        
        is unlikely to provide a warranty for its smashed up material
        
        will not be able to confirm its k value now that the ODP has been lost
        
        Question: is this work being done under an Energy Performance Contract (EPC)?
        
        Will the disintegrated foam insulation be effective as an insulation?
        
        Will a plastic foam minus its ODP gases have a useful k value?
        
        Will it compact down to close the air pathways through the interstices between the fragments?
        
        Is avoiding overheating a criteria for EPC success?
        
        Plastic natural cenforce soft 100 mg insulation will not provide decrement delay to protect from solar radiant heat gains through the opaque roof coverings