DPC level insulating suspended floor

3 Dec 2015
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United Kingdom
I have a 1980 house that in one ground floor room I am replacing the chipboard floor. While the floor is up I intend to insulate with 100mm Celotex etc, I will do the other rooms as I gradually renovate/modernise.

The construction of the floor is as per the diagram; a classic suspended floor on bricks on a concrete sub-floor, loads of air bricks, and all very dry which is great.

To make it airtight it has been suggested that I should expanding foam fill the gap between the end of the insulation and the wall. My concern is that this is across/below the DPC (which is 225mm above ground inside and out)

I have to protect/duct the air bricks to below the joists I know, approx 25mm of the insulation will be above DPC 75mm below.

Is it ok to seal to the wall below/ bridge the DPC?

Thanks in advance for the guidance!


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