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Damp Proofing Question
Basement/ground floor flat has no damp-proofing
We live in a maisonnette flat - the lower ground (basement) floor is an open plan kitchen/living room/dining room, and the ground floor has a living room, bedroom, bathroom and hallway. We have the bottom two floors of a 4-story detached stone house (not sure of the age - early 1900s I think).
My husband has lived in the flat for 10 years. In the past couple of years we have had an increasing problem with damp, throughout the whole flat but particularly on the bottom floor. We got someone round to look at it recently, and it transpired that there is no damp-proofing or tanking in the flat. This fact was not revealed when my husband had the Homebuyers survey done before he bought the flat.
We have been informed that to deal with the damp problem, we'd need to spend around £17,000 on the tanking/damp-proof course... money which we simply do not have.
We were planning to sell our flat and move on in the next couple of years; our fear now, obviously, is that we will never be able to sell the flat without getting the damp proof course put in.
So my questions are: a) is there any easier/cheaper way of dealing with the damp; b) if we don't get the damp-proof course put in, is there any way on earth anyone would still buy our flat (I realise we'd have to reduce the price to reflect the lack of damp-proofing)?!
It's quite a dire situation we find ourselves in, so any advice greatly appreciated!!
if you think logically, a basement is positioned below ground level which means there is damp surrounding all external walls below ground level, this causes hydro-static pressure, meaning moisture is pushing against your walls and trying to get in, the answer to this problem in my opinion and 15 years of experience is CAVITY DRAIN MEMBRANE CDM this together with parameter channels and a sump/pump will control and manage the Ingres of moisture.
this will be the most expensive solution to the problem, however it depends on what sort of existing floor covering you have, and how many external walls are below ground level you may be able to dramatically reduce costs.
if you have carpet on concrete floors, you will need to strip the external walls which are below ground level back to bricks, the contractor then will be able to chase channels approx 200x200mm at the bottom of the external walls and create a chamber for the sump/pump and connect 42mm pipe to external drains for the pump discharge. stud the walls board and plaster.
i would also recommend to fit HEAT RECOVERY FAN to create ventilation,
unfortunately there is no cheap or simple fix for untreated below ground basement walls,
an estimated cost for the above suggestion will be £400 per liner mtr of external walls. this includes stripping,channels,membrane, stud walls and plastering,
sump/pump approx £600-900 depending on the room size.
hope this helps.
Answered 10th Nov 2012
If the areas affected are below ground level then it needs to be tanked the only way you can save on costs is to have the areas affected treated not the whole flat it is not the ideal way of treatment and you will have to live with the fact that you are transferring the problem to the next purchasers ,the damp proof course is only needed above the exterior ground level to stop rising damp to the upper levels of the flat .
Answered 28th Oct 2012