Need help with water under the house problem please.
Discussion
We have rising damp in our sitting room and its not hard to see why. Looking into the foundations two feet below the floor, there is a substantial lake some two to three inches deep. I know its been very wet but FFS.
The house is a typical 30's semi with suspended floors. We are on a hill and the attached semi is about two feet lower than us. The room in question has already been tanked below floor level, as has the adjoining semi. Why is a bit of a mystery. It is the damp course which has failed.
We have an extension across the entire back of the house, which has a concrete floor and was built with deep foundations to allow further work if required. We have block paved the front of the house but it is not lined so water soaks into the ground as before. We have a patio at the back but this is pretty porous too. We have a soakaway in the garden to take he water off the extension.
The ground is clay and is saturated now but is always pretty moist a couple of feet down. When it rains the water under the sitting room - now in the middle of the house remember - appears quite quickly and takes ages to go away again. We are pretty confident that there are no burst pipes or leaking drains and the front of the house is dry. Obviously, the clay soil and rain, coupled with a being on a hill all contribute to the problem, and we know that this area - Bromley - does have drainage issues as well as hidden springs and wells.
We have a damp specialist ready to deal with the failed damp course and resulting damage, and they are also going to spray the timbers in the sitting room but will not guarantee that part of the work as water will still be sitting under the floor, ultimately condensing all over the timber and rotting it.
The question is, how do we establish where the water is getting in, and why, how the hell do we stop it? We need to sort this out as it is unlikely to get better on it's own and is obviously going to cause problems in the future. Land drains have been suggested, running into next door's garden to take water off our's, and there were drains in the garden at some point but these were all blocked and broken by the time we did the extension. Doing away (illegally) with the soakaway and running that into the sewer has also been suggested. Could we build a concrete wall round the foundations to keep the water out?
All suggestions gratefully received and there's a job here for somebody too.
Thanks
The house is a typical 30's semi with suspended floors. We are on a hill and the attached semi is about two feet lower than us. The room in question has already been tanked below floor level, as has the adjoining semi. Why is a bit of a mystery. It is the damp course which has failed.
We have an extension across the entire back of the house, which has a concrete floor and was built with deep foundations to allow further work if required. We have block paved the front of the house but it is not lined so water soaks into the ground as before. We have a patio at the back but this is pretty porous too. We have a soakaway in the garden to take he water off the extension.
The ground is clay and is saturated now but is always pretty moist a couple of feet down. When it rains the water under the sitting room - now in the middle of the house remember - appears quite quickly and takes ages to go away again. We are pretty confident that there are no burst pipes or leaking drains and the front of the house is dry. Obviously, the clay soil and rain, coupled with a being on a hill all contribute to the problem, and we know that this area - Bromley - does have drainage issues as well as hidden springs and wells.
We have a damp specialist ready to deal with the failed damp course and resulting damage, and they are also going to spray the timbers in the sitting room but will not guarantee that part of the work as water will still be sitting under the floor, ultimately condensing all over the timber and rotting it.
The question is, how do we establish where the water is getting in, and why, how the hell do we stop it? We need to sort this out as it is unlikely to get better on it's own and is obviously going to cause problems in the future. Land drains have been suggested, running into next door's garden to take water off our's, and there were drains in the garden at some point but these were all blocked and broken by the time we did the extension. Doing away (illegally) with the soakaway and running that into the sewer has also been suggested. Could we build a concrete wall round the foundations to keep the water out?
All suggestions gratefully received and there's a job here for somebody too.
Thanks
Could you install a sump pump?
If you have an effective damp course this would not however result in rising damp (assuming the water level stayed below the course)
http://www.safeguardeurope.com/products/basement-s...
If you have an effective damp course this would not however result in rising damp (assuming the water level stayed below the course)
http://www.safeguardeurope.com/products/basement-s...
B17NNS said:
Could you install a sump pump?
If you have an effective damp course this would not however result in rising damp (assuming the water level stayed below the course)
http://www.safeguardeurope.com/products/basement-s...
It has been suggested but still leaves the original problem which I would like to deal with if at all possible. However, a pump cannot be ruled out. Just a thought - where do these things discharge? If you have an effective damp course this would not however result in rising damp (assuming the water level stayed below the course)
http://www.safeguardeurope.com/products/basement-s...
The room in question has already been tanked below floor level, as has the adjoining semi. Why is a bit of a mystery. It is the damp course which has failed.
Am I understanding correctly about this tanking? Have you in effect got a pond liner under your floor?
I would want to know first how the water is getting there, is it seeping through the floor/the walls? What about the drains around the house? which way does the ground slope Even porous paving diverts a heck of a lot of water.
I would dig a hole at the lowest point of the sub-floor and sink a drum in it with a pump in that. A sump pump. Should be able to pump out to the drains.
Am I understanding correctly about this tanking? Have you in effect got a pond liner under your floor?
I would want to know first how the water is getting there, is it seeping through the floor/the walls? What about the drains around the house? which way does the ground slope Even porous paving diverts a heck of a lot of water.
I would dig a hole at the lowest point of the sub-floor and sink a drum in it with a pump in that. A sump pump. Should be able to pump out to the drains.
OK, well damp is always a challenge in a property, but I would be sceptical of any advice you have been given by a damp proofing company. They make there money by selling damp treatments!
It sounds like its unlikely to be genuine rising damp in the the property to be honest, a failiure of the DPC may have occured, but this could equally be a case of condensation on the lower walls due to the high humidity levels from having water in the sub floor. As a result I would delay having the DPC work done for at least a couple of months after the subfloor issue is resolved as you may find that it is unnecessary once everything has dried out. A 30's property is likely to be fitted with a slate DPC I would guess rather than bitumen? These are quite effective under 'normal' conditions but if water is sat in the subfloor then they are not perfect and water can bridge them giving the effect of a failed DPC, whilst actually the problem is the subfloor moisture content. What is the building constructed from? I am presuming brick? If its 30's is it rendered? If so and this falls below your DPC then this may provide the bridge for moisture to appear above the DPC - a common problem where properties have been rendered.
The 'tanking' you refer to, may actually not be helping the cause here. People often mistakenly think that by trying to tank a space you make it more water proof, however you say that the water appears very quickly and then dissappears very slowly. If that is the case then it could well be that the tanking is actually preventing the water from draining away in the manner it may normally do. It would be interesting to have some more information about the subfloor and 'tanking'. Is the subfloor straight onto the earth? The most likely given the age of the property I would think? Buildings have a natural tendence to absorb moisture and then effectively 'wick' it out, so tanking can occasionally push the moisture to appear elsewhere.
Often with extensions etc where a DPM has been installed under a new concrete floor you force the moisture out to the surrounding areas. In areas with a high water table and an extension with very deep foundations then it may be that the footings are pushing out a considerable amount of water which is materialising in your subfloor as it has no where else to go.
It seems strange that the properties have been tanked though - this would make me suspect however that this not a new problem and one that may have occured before.
Some photos of the subfloor would be useful in trying to work out what has happened, perhaps along with some photos of the site so I can understand the elevations and site layout. You are welcome to email them to me if you want. I can't promise a solution but happy to spend a few minutes looking at it for you.
It sounds like its unlikely to be genuine rising damp in the the property to be honest, a failiure of the DPC may have occured, but this could equally be a case of condensation on the lower walls due to the high humidity levels from having water in the sub floor. As a result I would delay having the DPC work done for at least a couple of months after the subfloor issue is resolved as you may find that it is unnecessary once everything has dried out. A 30's property is likely to be fitted with a slate DPC I would guess rather than bitumen? These are quite effective under 'normal' conditions but if water is sat in the subfloor then they are not perfect and water can bridge them giving the effect of a failed DPC, whilst actually the problem is the subfloor moisture content. What is the building constructed from? I am presuming brick? If its 30's is it rendered? If so and this falls below your DPC then this may provide the bridge for moisture to appear above the DPC - a common problem where properties have been rendered.
The 'tanking' you refer to, may actually not be helping the cause here. People often mistakenly think that by trying to tank a space you make it more water proof, however you say that the water appears very quickly and then dissappears very slowly. If that is the case then it could well be that the tanking is actually preventing the water from draining away in the manner it may normally do. It would be interesting to have some more information about the subfloor and 'tanking'. Is the subfloor straight onto the earth? The most likely given the age of the property I would think? Buildings have a natural tendence to absorb moisture and then effectively 'wick' it out, so tanking can occasionally push the moisture to appear elsewhere.
Often with extensions etc where a DPM has been installed under a new concrete floor you force the moisture out to the surrounding areas. In areas with a high water table and an extension with very deep foundations then it may be that the footings are pushing out a considerable amount of water which is materialising in your subfloor as it has no where else to go.
It seems strange that the properties have been tanked though - this would make me suspect however that this not a new problem and one that may have occured before.
Some photos of the subfloor would be useful in trying to work out what has happened, perhaps along with some photos of the site so I can understand the elevations and site layout. You are welcome to email them to me if you want. I can't promise a solution but happy to spend a few minutes looking at it for you.
Thanks for your comments and I will get some pics taken later on today.
It has been mentioned that the subfloor appears to be concrete, possibly with a polythene liner under it. Our neighbours recall a serious flooding event being discussed but don't know much more than that, or why they and us have been tanked. It certainly would seem that we have the potential for a swimming pool if we add a few tiles...
The house is typical 30's - brick, rendered at first floor level to the front and all the way round elsewhere. The front shows high levels of damp too, both in the wall at skirting level and in the floor timbers but there is no standing water; it is very dusty in fact. The subloor slopes down towards our adjoining semi and in the middle of the house - by the stairs - is only about a foot down.
Looking at the garden from the back of the house, it slopes from left to right (where we are joined) and from the far end towards the house. The top of the path is a puddle, as was the house end on Monday during the heavy rain.
Significantly, when the extension was built there were small drainage pipes running off the garden, presumably into a much larger pipe running from left to right, effectively down the hill. All of the minor pipes were broken and clogged up. The major pipe, around two foot diameter, had a tree root in it (which was bridged by the foundations) and was also broken and very clogged. Unfortunately, this is now almost lost under the house, although there is a cover under the tiled floor in the kitchen.
I will get some pics done over the next 24 hours ad post them up.
It has been mentioned that the subfloor appears to be concrete, possibly with a polythene liner under it. Our neighbours recall a serious flooding event being discussed but don't know much more than that, or why they and us have been tanked. It certainly would seem that we have the potential for a swimming pool if we add a few tiles...
The house is typical 30's - brick, rendered at first floor level to the front and all the way round elsewhere. The front shows high levels of damp too, both in the wall at skirting level and in the floor timbers but there is no standing water; it is very dusty in fact. The subloor slopes down towards our adjoining semi and in the middle of the house - by the stairs - is only about a foot down.
Looking at the garden from the back of the house, it slopes from left to right (where we are joined) and from the far end towards the house. The top of the path is a puddle, as was the house end on Monday during the heavy rain.
Significantly, when the extension was built there were small drainage pipes running off the garden, presumably into a much larger pipe running from left to right, effectively down the hill. All of the minor pipes were broken and clogged up. The major pipe, around two foot diameter, had a tree root in it (which was bridged by the foundations) and was also broken and very clogged. Unfortunately, this is now almost lost under the house, although there is a cover under the tiled floor in the kitchen.
I will get some pics done over the next 24 hours ad post them up.
rlw said:
Significantly, when the extension was built there were small drainage pipes running off the garden, presumably into a much larger pipe running from left to right, effectively down the hill. All of the minor pipes were broken and clogged up. The major pipe, around two foot diameter, had a tree root in it (which was bridged by the foundations) and was also broken and very clogged. Unfortunately, this is now almost lost under the house, although there is a cover under the tiled floor in the kitchen.
I will get some pics done over the next 24 hours ad post them up.
I would get in contact with the local council and water board and ask to see their maps - ask about land drains - they may charge for this - but a 2ft pipe is huge, there is a stream near me which has been piped under some gardens and that is only a 9 inch pipe. But I would be concerned that there are old drains of some sort running down the hill and because of the damage some of that is being diverted into your water feature.I will get some pics done over the next 24 hours ad post them up.
Also look into the possibility of a french drain or eco drain across the back of the house. Ground sloping towards the house isnt great.
I agree with pretty much everything Tim says as well.
Solitude said:
Gonna get hell for this, but i thought it was a Sub (submersable) pump.
Sump pump ??
A pump that lives in a sump. Sump is basically a container (hole) for collecting the fluids.Sump pump ??
Sump pumps tend to be permanent or semi permanent fixtures.
A submersible pump could be a sump pump as it is a pump you put in the fluid to allow it to be pumped somewhere.
Firstly I am not a specialist in this field but can offer a solution that cured a friends similar problem.It was down to the water table,the 3 to 4 inches of water were filled with the same depth of gravel,a membrane was installed and topped with a further 2 inches of stone.This appeared to cure the problem,however belt and braces he also installed a land drain around the offending area.Three years ago and no recurring problems.Good luck.
bazjude2998 said:
Firstly I am not a specialist in this field but can offer a solution that cured a friends similar problem.It was down to the water table,the 3 to 4 inches of water were filled with the same depth of gravel,a membrane was installed and topped with a further 2 inches of stone.This appeared to cure the problem,however belt and braces he also installed a land drain around the offending area.Three years ago and no recurring problems.Good luck.
bazjude2998 said:
Firstly I am not a specialist in this field but can offer a solution that cured a friends similar problem.It was down to the water table,the 3 to 4 inches of water were filled with the same depth of gravel,a membrane was installed and topped with a further 2 inches of stone.This appeared to cure the problem,however belt and braces he also installed a land drain around the offending area.Three years ago and no recurring problems.Good luck.
How has that cured the problem? Hasn’t it just masked it? I have about a foot of water in my cellar, and now that it is winter, it is staying! Installing a sump pump means that the pump will be running constantly through the winter, which is not ideal. I am going to have to wait for the ground water to drain away (hopefully in summer - cellar was bone dry this summer), and then get in there and see if we can tank whilst responsibly draining ground water away rather than redirecting it somewhere else.
Not fun. The smell isn't nice either when you open the cellar door! I drain it with a puddle pump every few days, just to change the water.
Not fun. The smell isn't nice either when you open the cellar door! I drain it with a puddle pump every few days, just to change the water.
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