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Closing up an (internal) chimney breast

2 Posts
2 Users
Posts: 1
Topic starter

We are removing a gas fire and replacing it with a radiator. The chimney breast is on the internal party wall with our neighbours (1930s brick built semi).

We are trying to figure out what needs doing for ventilation and insulation of the (now retired) chimney. Do we fill the whole thing with insulation, or is there a simpler solution?

Posted : 06/11/2023 11:15 am
Posts: 80
Member Admin

Hi Andy.

I would suggest filling the void with an inert insulant, such as Vermiculite, so that there is no air movement up through the chimney to take heat away from either you or your neighbour. If you take this up to the insulation envelope of your house then you will large stop most of the heat loss into the structure. The top of the stack would then be capped off with a vented cap to allow a small amount of air exchange.

Hope that helps.

Posted : 16/11/2023 3:23 pm

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