CWI, Impermeable masonry paint (update)

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In my previous post I outlined the problem with installing CWI in buildings with water impervious paint and how it can lead to premature failure of masonry or render.

I finally got a response from Energy Saving Trust

"It is certainly the case that adding a coat of paint or other material with lower vapour permeability to a wall with relatively high permeability will affect the way moisture can travel through the wall. It is also the case that adding insulation to a wall at any point will also affect the way moisture behaves and travels within the wall.

Standard cavity wall insulation is widely accepted as an appropriate solution for many common brick and brick or brick and block cavity walls in areas of low exposure, and so guidelines for safe installation are mainly targeted at these wall types. If the wall has been externally painted with a low permeability material, then these guidelines may not be sufficient to minimise risk of unintended consequences, and so we advise that the pre insulation survey takes full account of the situation, and the likely behaviour of moisture in the wall post insulation. We are not in a position to determine if insulation would be appropriate or not in such a wall – a site inspection by a suitably qualified assessor will be necessary to make that judgement, and that is why we recommend that they survey takes full account of the circumstances.

If you believe that your wall was not suitable for the insulation it received then you should contact your installer in the first instance to ask if they can help resolve your issues. If you are unable to contact them, or if they are unwilling to help, then you should contact CIGA. The should be able to determine whether the installer followed all the appropriate guidelines before and during installation, and provide support for remedial action if appropriate."

I'm grateful for the Energy Saving Trust for providing this information however I really can't imagine cavity wall installers ever giving a thought to the building fabric. The norm for CWI is that even the most basic pre survey assessments of the cavity were not done and our house is a perfect example - narrow cavity, overspill into the loft, rubble, mortar droppings, obstruction and electrics in the cavity and massive gaps in the insulation.

A common theme from any agency or politician who has ever promoted CWI is to advise contacting CIGA. All roads lead to  CIGA it seems.
Well the reason we contacted EST because not only had CIGA completely ignored my concerns about the impermeable paint and the problems with water getting in through the poorly cemented drill holes but their CEO Nigel Donohue has basically said that CIGA will not communicate with me further due to my 'tone'.

Good technical advice for consumers on this issue is very hard to access. Bear in mind that building control don't get involved. The BBA have washed their hands of the issue because they will not investigate problems with system designers who are no longer trading despite rating the insulation as suitable for the 'life time of the building'.

The whole lot stinks.

I do not trust CIGA to assess the fabric of a cardboard box let alone a building. Bear in mind that when one inspector visited my property he knocked on a solid, dull sounding piece of render and said that it was hollow and de-bonded as if I'm some sort of idiot.  

Comments

  1. PAULINE SAUNDERS - CIVALLIDAMP@GOOGLE.COM14 February 2019 at 01:27

    You are an inspiration and make me cheer at your bravery and laugh at your comments, which are SO accurate, and backed up with solid evidence.

    ReplyDelete

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