DPM under block and beam

[blake floyds]

I plan on putting a DPM on top of my block and beam ( under celotex and lapped in with dpc) floor but when i was speaking to the build inspector he said i need one under the floor as well is this right cus my brickie said its not
and I do not see the point in having 2

 

[^woody^]

You normally have a DPC under the beam bearings, and no need for a DPM on a suspended B&B floor

 

[blake floyds]

ok thanks

 

[jeds]

There are two situations when a dpm may be required. If your floor level is below adjoining ground level and if you are in a radon affected area. If neither of these apply and you have the regulation voids etc. then you do not need one. Although for fifteen quid I always specify on myself - exactly as you descirbe; on the blocks and under (or over) the insulation.