Cavity wall insulation and what to do when it is causing damp in my home

southwell

I would be very grateful for some advice. We had cavity wall insulation installed some years ago by a company that is no longer in business. We have had so many problems with damp that we never had before and have a CIGA guarantee. However when I have contacted CIGA to say I want the insulation removed they don’t want to know and say it is caused by poor ventilation and me as the home owner. This is not true and I have asked for this to be escalated and be properly investigated. I don’t believe that the installation was carried out with the right stuff or that the house was surveyed correctly. I think the company just wanted to draw down the funding to put in the installation. Please can anyone offer any advice what I can do and or how I go about getting this insulation removed privately (although I think CIGA should pay). We have spent so much money on redecoration and followed all advice on condensation yet the problems persist. 

Thank you 

Neil_Jones

What sort of damp is it?  Rising damp, penetrating damp and condensation are the three most common types of damp for residential properties.
https://www.which.co.uk/reviews/damp/article/dealing-with-damp/what-kind-of-damp-is-affecting-my-home-arNnf1P2wVnV

southwell

I would say condensation 

MWT

You may find there is nothing wrong with the cavity insulation, simply that your exterior walls are in poor condition and are allowing moisture to penetrate which is then wicked across the cavity by the insulation.

If that is the case, the fix is not to remove the insulation, but to treat the exterior walls...

Has anyone actually been to your property to determine the actual problem ?

[Deleted User]

Deleted post

tacpot12

You need an expert opinion. You have asked CIGA to investigate, but I don't know whether they are obliged to pay for an investigation. It is also a moot point as to whether you would want CIGA to investigate given that they have a vested interest in finding against you. I think you need you find your own expert assessor - perhaps you could ask for their track record against CIGA! If the expert says it is not the insulation causing the problem, there are other solutions to condensation such  as localised heating and positive input ventilation.  

The assessor may be able to recommend a company that can do the removal. I don't know a lot about cavity wall insulation, but I expect that any installer could remove your insulation if it is of the type that they install (disassembly is the reverse of assembly). The assessor may be able to confirm the type of insulation that you have if you don't know. 

The potential for penetrating damp being the cause is also valid. It could be worth treating the external walls with silicone to prevent this. You could try one wall first to see if it cures the problem, before investing in treatment for the rest of the walls. 

southwell

Thank you but where would I find an expert assessor ? 

[Deleted User]

Agreed that the OP should seek an expert opinion if they are concerned anough to want the cavity wall insulation removed.

Petriix

Ignore the ill-informed advice, people mean well but damp is a bit of complex issue.

Modern houses are designed to be watertight with properly considered exit routes for any water that penetrates the outer skin of the cavity walls. Many older houses were built with the principle that the materials were porous and needed to 'breathe' in order to allow water to escape.

Older cavity walls use the physical separation between the layers to keep the water away from the inner skin. Soft brick and lime mortar walls will let water through, even when properly maintained. The problem is exacerbated where walls are regularly exposed to driving rain.

As these older walls don't have proper damp proof membranes and weep bricks to direct the water out, they rely on the porous nature of the materials to allow the water out again. Unfortunately, if the cavity is bridged by insulation, the water is now able to use the inner skin of the wall to exit as well as the outside. Such walls were never suitable for cavity wall insulation. 

I'm not clear on the legal redress available, but the physical process is quite straightforward: either prevent the water from getting in, or give it a way out. Your interal plaster is likely trashed anyway so you can simply hack it off and replace it with a lime based render (at least at the bottom, where the damp is) and then use a breathable mineral paint. Alternatively remove some of the clumped up, damp insulation from the base of the wall and install some cavity trays and weep bricks to encourage the water to exit externally.

[Deleted User]

If my advice was indeed ill informed thanks for pointing it out   I have deleted all comments relating to this issue.  Can the OP please ignore everything I said about condensation as what I posted was never intended to be anything other than personal.  I did suggest that the OP should seek an expert opinion

southwell

It I am to seek an expert opinion to survey my home then where do I find such a person please ?