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Damp Proofing Question
Very difficult to set a sump pump in wet cellar
I live in an old cottage set on a Pennine hillside which has a vaulted cellar.
The cellar is currently damp and in really wet conditions water can be seen at the edges of the flag stones.
The water is only ever in one corner of the room but the opposite corner appears dry (in fact I have ran a hose pipe down there for a few hours and the water totally drained away).
When I lifted some flag stones I had a dig around to see what the ground was like underneath and after only about 1" of digging I hit solid bedrock.
It looks like the water is due to a natural water course which runs along this bedrock.
Therefore it doesnt look like installing a sump pump would be possible as I would need to literally chisel into the rock. Also as the house is old I wouldnt want to try and alter the natural water course which the house has always been sat on.
Given that the water is only ever in one corner and the level of water never comes above the flag stones (I have been watching for about 3 years now) would I get away without a sump pump if I were to try and use a membrane tanking system ?
Otherwise would a more traditional concrete + DPM type floor be better as this would raise the floor level 3 or 4 " ?
Any advise would be appreciated.
You can only use cavity drain membrane in a tanking situation if it has drainage or a sump pump. The system is not designed to cope with static water pressure and any build up would certainly result in failure. The british standard for this type of system tells you that even if there is no history of flooding we must assume that some flooding will occur in the future.
The pump does not necessarily have to go in the damp corner - if there is earth elsewhere in your cellar you could dig there and form a drain to that point.
Mike Davison cssw
Answered 27th Apr 2012
Hi lee lift flags lay membrane system to floor using w/proof jointing tape wich can be purchased with membrane lay fluted drainage channel at lowest point with exit to outside wall hope this helps [log on to wycamol web site for info ] kind regards kevin
Answered 26th Apr 2012