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Postby alfiehines » Thu Mar 15, 2007 2:34 pm

Hi All,

I am in the process of buying a house and had a home buyers survey done on it. One of the areas that was highlighted was the fact that "The wall and patio to the rear are over the level of the damp proof course and should be reduced 150mm below the damp proof course level". There is no sign of damp at the moment. The walls and patio go right up to the house wall and a small conservatory is on the patio.

Is this or will this be a problem in the future?

It seems a very large job to lower walls and patio especially when there is a conservatory on the patio.

Is there some preventative measure i can take without lowering?

Lots of questions i know but i would be most grateful for any advice or help given.
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Postby mikester » Thu Mar 15, 2007 7:27 pm

I've seen loads of surveyors reports with this on, its usually nothing to worry about, if there were any damp readings inside the house this would be on the report.

He's just making a point that it's not upto modern building regs.

If its an old house:
Have a look at the outside of the building around shin height and if you can see a horizontal line of holes (usually with plugs in ) about every 10cm or so, then the building has already had a chemical damp course injected. This is the normal remedy for penetrating damp.
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Postby alfiehines » Fri Mar 16, 2007 8:17 am

Thanks Mikester, That was just the kind of answer i was looking for. There are no signs of damp in the house and the walls and patio have been there since before 1998 so hopefully that trend will continue.

One final point, you mention Chemical Damp Proofing, would it be prudent to get this done as a preventative measure and if so, will this protect the house wall below the level of the patio?

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Postby thedoctor » Fri Mar 16, 2007 2:43 pm

A horizontal line of holes is NOT A REMEDY FOR PENETRATING DAMP its a sign that a dpc has been injected to stop RISING DAMP which is a completely different ball game entirely.

The patio should be lowered as the surveyor suggests, this is for your benefit and will help you sell if ever you want to. A chemical, or any other DPC is absolutely pointless any higher than floor level. It is there to stop water rising up the wall above the floor level and getting into the building. If the patio is already at Floor level (DPC) then any water, rain splashes etc, getting onto the wall can, if there is any fault in the cavity, or if the brickwork is solid, soak through the wall and come out inside the building. PLease see our projects on DPC injection, Rising Dam, Damp and mould and French drains. The very least you should do is excavate a trence against the wall after cutting away 350mm of paving at least 400mm deep and fill it with pea shingle to allow any water to drain down below the foundations.

If the wall has been soaking up water since 1998 it needs doing, it does not mean it will stay OK for the future.
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