Patio and Damp Course

12 Jan 2005
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United Kingdom
Hi all, I live in a house built in the early 70's and i'm about to lift the original patio in back garden and lay new paving.
The issue I have is that the exsisting patio is only one brick below the damp course, some thing that has always bothered me. We have suffered from condensation problems for years and I have often wandered if this is the reason why.
I really didn't want to dig down another 8" to give 2 bricks clearence due to the fall of garden. Patio is runs out 3.5m and falls away from house but once it meets grass the slope rises, so if i dig out another 8" at the house end and keep the fall I will end up going a lot lower than the grass level. I considered putting a small wall and step at end of patio against grass but this will push up the expense and create a lot more work. Any ideas would much appreciated.
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Just been doing some research and it looks like if I buy a drainage channel and lay the full length of house wall I could keep my level at only one brick below damp course. Can anyone confirm this ??
That's not really true its just someones opinion.

Whilst building a new extension or new build house is subject to building control and must adhear to the building regulations you doing a replacement patio on your own house do not.

Anything less than 150mm gives you a risk of spashback and you will get spashback from a linear drain grate just the same as a paving slab.

I have seen plnety of patios 50mm or less below dpc with no problems but then have seen one 100mm below with damp issues.

So to cut a long story short its your call so as long as your aware of the risk then you know the score.
Thanks for the reply. As I said, house was built in the 70's and I presume the slabs we're laid at a similar time. I have lived here 18 years and we don't have any damp issues but we do suffer from condensation on the windows during winter months. Not sure if that's related !!

I have now been and purchased the drain channels and i'm going to attempt to fit it as close to 2 150mm below dpc as possible even if its slightly lower than the first row of slabs.

Thanks again
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If it was my house i would not worry until it was less than 75mm. but its best to be on the safe side.

Having the channels a bit lower than the slabs as you say will present no problems really.

The condesnation is almost certainly unrelated unless it was solely allong the base of the walls

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