Extension - DPC above floor. INspector will not sign off.

13 May 2013
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United Kingdom
I have a 1940 built house that has just been extended. The builder was contracted to build the extension and install wet underfloor heating (UFH) on the entire ground floor including the old part of the house. The original floor was floorboards over a void under which was concrete.

During the construction I asked the builder if it would be possible to LOWER the floor level of the entire ground floor so I could get taller ceilings and he said yes (New door frames and stairs were installed too).

A DPM was laid was laid on the floor of the extension and over the concrete on the original section of the house. Then celotex was laid over the new concrete in the extension and over the old concrete of the original house and pipes clipped onto this. Th entire ground floor was then screeded.

Now the building inspector will not sign off because the floor level is BELOW the DPC in the extension.

Is there a fix for this situation that would persuade the Inspector to sign-off without a huge costs.

Your help is appreciated.
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You will never persuade a building inspector, as these things are recorded officially.

Was this shown in the submitted approval dwg. and/or indeed was there any dwg. submitted for approval??...pinenot :)
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Now the building inspector will not sign off because the floor level is ABOVE the DPC in the extension.

The DPC is ABOVE the Floor Level (i.e. the Floor is BELOW the DPC).

Confused....you won't be!

You need to take measures to ensure that the exposed masonry below the dpc can not effect the plastering etc and can not wick up any damp.

Either a physical membrane or dpc injection i guess.

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