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What about my neighbours?


I live in a Victorian, solid walled, mid terrace with external decorative stonework.

I've looked into IWI in the past and one factor that has discouraged me is knowing that if I installed IWI at the front of my house, then I'm potentially going to create cold spots the other sides of my party walls in the neighbouring properties.  -which in turn could lead to condensation and mould problems for them.

Does anyone know what the legal position of this would be?

And any way I could avoid it without compromising my own insulation levels or requiring the neighbours to install their own IWI at the same time?

Topic starter Posted : 10/03/2021 7:32 pm
Chris Brookman
Member Admin


I'm not sure this is something I've ever come across and is not an issue that I'm aware of. Insulating your side of the wall is not going to result in any cold spots on the neighbours wall that won't be rectified by their own heating.

Generally you insulate the interior face of your external walls and also return some insulation, even if it is only 20mm thick, 500-600mm along the party walls to reduce the heat loss from the party wall meeting your external walls.

Hope that helps.

Posted : 10/03/2021 8:23 pm


Thanks Chris, 

This isn't something that I have personal experience of,  just something that I've figured out from first principles. 

If I can get access to a 2D heat transfer solver, I'll try to model my wall situation and see if I can quantify the effect.

Topic starter Posted : 11/03/2021 9:33 pm

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