damp proof corse

9 Feb 2007
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United Kingdom
hello knowledgeable ppl

someone has built an extension to our house, and the problem is the dpc is @ 9" above slab (1 block up from the concrete slab) the slab is the internal floor level

The blockwok has been rendered to the slab outside and to within 2" of slab level inside hence the dpc is bridged inside and out i have knocked off the render o/s to about 1" above dpc and the plaster inside to the same as to dry the wall this is now very unsightly what can i do (short of knocking it down & rebuilding it)

I obviously need to replaster inside to just behind the skirting but this will breach the dpc by 3"

I was planning a plinth almost up to dpc o/s and leaving a gap then continuing the render with a bell cast drip above the dpc?

Any advice??
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Can you do a photo, I think I know what you mean but want to make sure.
why on earth did they build it up so high in the first place?

did you buy the house like this or did you have the extension built yourself?
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well i assume the they went for the minimum 150mm rule on the outside ,

So the result is that the dpc is high enough o/s no to soak up water but the inside is efectivly below ground level

obviously i cannot lower the dpc i can lower the o/s ground level but i still need to plaster over inside

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