This week in the Examiner, Kieran McCarthy of KMC Homes provides advice on how suspect ‘DIY’ wall insulation may conceal a whole host of problems.

Q. We have bought an older-era home in the country that the previous owners did some upgrade works on. It’s pretty well insulated now in the attic, and most external walls have been slabbed with 50mm insulated plasterboard which appear to have been ‘stuck’ to the old walls, a mix of brick, block and some stone too. I read that older stone walls should be allowed to ‘breathe” but that can’t happen in this case? There is no sign of any mould or damp inside or outside at present, but we worry about the years ahead. Should we remove this and replace it, or take our chances and leave it as is unless some issue manifests itself, which clearly would be our preference given the disruption and costs after only recently buying it. It got a G BER when assessed for sale as the slabbing had been a DIY job and the BER assessor didn’t examine its depth, we were told. Thanks, Ann and Andrew

A. You mentioned that there has been some insulation added but that the house is still a G Ber. This is a pity because it suggests that you have lost some of the internal features whilst not benefiting from a dramatic improvement in energy efficiency. So, what next for your home? Firstly, as you are proposing to work on more than 25% of your external envelope (outer shell) of your home, you will need to comply with the relatively new NZEB regulations. This broadly means that you will need to bring your entire home up to a B2 BER rating. This will of course mean reviewing your heating system, external windows, airtightness and, of course, insulation, but let’s concentrate on the insulation for now. Even though you can’t see any mould on these walls I would be very surprised if there aren’t significant issues buried in the fabric of this ‘newly applied’ finish, given that this was applied in a handyman fashion.

View full article in The Examiner here.




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