Report - High risk subsidence, anyone had this?
Discussion
Hi PH people,
Looking at a house and survey is saying it in a postcode for high risk subsidence (supposedly based upon ins claim data) then goes on to say 30% of postcodes fall into to high risk or very high risk...
Anyone else had this - worth getting the sweats over?
House is Wokingham in South East. Around 1930s period property. Don't seem to be any major trees nearby which seems to be the main cause of subsidence but I guess a house of that age could have flakey/leaky drains. Someone even said ti might have lead pipes - is that really likely to be the case?
Looking at a house and survey is saying it in a postcode for high risk subsidence (supposedly based upon ins claim data) then goes on to say 30% of postcodes fall into to high risk or very high risk...
Anyone else had this - worth getting the sweats over?
House is Wokingham in South East. Around 1930s period property. Don't seem to be any major trees nearby which seems to be the main cause of subsidence but I guess a house of that age could have flakey/leaky drains. Someone even said ti might have lead pipes - is that really likely to be the case?
Depends on where you're looking, one clue would be to see if any of the other houses have moved.
The bit of Wokingham I'm familiar with had quite a few cases of visible movement, few potential causes but I was always a bit suspicious of it being shallow foundations & there being proper wet clay under the soil - two or three feet down where I looked.
It was all historical movement though, nothing I saw had actively moved in at least a couple of decades. Usually gable walls that had dropped relative to the rest of the house.
The bit of Wokingham I'm familiar with had quite a few cases of visible movement, few potential causes but I was always a bit suspicious of it being shallow foundations & there being proper wet clay under the soil - two or three feet down where I looked.
It was all historical movement though, nothing I saw had actively moved in at least a couple of decades. Usually gable walls that had dropped relative to the rest of the house.
Jonesy23 said:
Depends on where you're looking, one clue would be to see if any of the other houses have moved.
The bit of Wokingham I'm familiar with had quite a few cases of visible movement, few potential causes but I was always a bit suspicious of it being shallow foundations & there being proper wet clay under the soil - two or three feet down where I looked.
It was all historical movement though, nothing I saw had actively moved in at least a couple of decades. Usually gable walls that had dropped relative to the rest of the house.
Hi JonesyThe bit of Wokingham I'm familiar with had quite a few cases of visible movement, few potential causes but I was always a bit suspicious of it being shallow foundations & there being proper wet clay under the soil - two or three feet down where I looked.
It was all historical movement though, nothing I saw had actively moved in at least a couple of decades. Usually gable walls that had dropped relative to the rest of the house.
We're you inspecting properties? The bit we are looking at is to East of Finchampstead road. I did spot from digging around that a developer wanted a housing development to go up around there but was declined due to amongst various other things the loss of ground to absorb surface water runoff/they also mentioned high water table for the area. We like the house just worried we are buying into a money pit!
A lot of the Southeast is clay, so movement in the house is always possible as in the old days foundations were not done as they are now, if anything 1930 is relatively later and older than that won't even have dpc's never mind any foundations!
Yes water pipes may be lead as still very common, but no biggie, you can get the water company to test for lead content, if it fail the safety level they will replace it for you. There is probably more lead upstream than the bit that is in the house.
What you need to look for is any recent movement, for example my house had cracks in the cornices, they had been filled but as the paint was so old, it clearly had happened a long time ago.
Talk to the neighbours in the area and find out if they have been affected.
In terms of getting the sweats over, that is up to you and your risk profile. If the house has been standing since 1930, there is no reason for it to not be standing in the future if maintenance is kept up.
Yes water pipes may be lead as still very common, but no biggie, you can get the water company to test for lead content, if it fail the safety level they will replace it for you. There is probably more lead upstream than the bit that is in the house.
What you need to look for is any recent movement, for example my house had cracks in the cornices, they had been filled but as the paint was so old, it clearly had happened a long time ago.
Talk to the neighbours in the area and find out if they have been affected.
In terms of getting the sweats over, that is up to you and your risk profile. If the house has been standing since 1930, there is no reason for it to not be standing in the future if maintenance is kept up.
Edited by hyphen on Thursday 29th June 13:51
Extensive ancient chalk mines in my part of the world resulted in a complete estate being demolished after several big holes appeared in the late 70's and floors/houses collapsing, and there are still problems occasionally with large holes appearing and swallowing cars and buses.
The irony is the council were aware of the danger when they built the estate but still went ahead.
The irony is the council were aware of the danger when they built the estate but still went ahead.
Purely from an amateur point of view I'd say that if you cannot see any signs of subsidence and your surveyor finds none, there are no trees or large tree stumps close to the house then the house is probably fine. Have a look at the neighbouring houses for any signs too, cracks obviously, but newly rendered walls, raised/lowered manhole covers etc. You can check the local council web site for any building control notices for the local properties and see if any of them have needed underpinning. Some people are put off by houses that have had a subsidence issue fixed, in some respects they are the ones that should now be fine and it will be the neighbouring ones that have had no work that are more likely to have an issue.
You will end up paying a bit more for the house insurance being in a known subsidence area, however if it ever occurs then you have the insurance to sort it out.
If you are worried about the drains you can get a drain survey done.
Our 1930s house had some lead piping which I removed as I did work, but none of it was live, all you can do is check under the sink, in the tank/airing cupboard, the loo and bathroom to see if there is anything obvious. If the kitchen and bathroom are going to be replaced then it will not be too massive a job even if you find some, assuming it isn't a huge house? You do not mention wiring, are you sure there is no rubber cabling lurking under the floors?
Sometimes it is hard to tell, we are about to knock down and rebuild a house, we knew next door had been underpinned, however it is on partially infilled land and has an old land/road drain pipe running on the far side of the property which may be cracked so thought it was down to a specific set of issues rather than the geology. When we had the ground survey done our structural engineer was surprised the house had not had major subsidence issues as while there was a good pebble filled sand/clay sub soil under the surface between 0.8 and 1.6m down this turned into wet soft sandy silt. That wiped out the idea to have a basement, the new house is going on piles and a ringbeam.
You will end up paying a bit more for the house insurance being in a known subsidence area, however if it ever occurs then you have the insurance to sort it out.
If you are worried about the drains you can get a drain survey done.
Our 1930s house had some lead piping which I removed as I did work, but none of it was live, all you can do is check under the sink, in the tank/airing cupboard, the loo and bathroom to see if there is anything obvious. If the kitchen and bathroom are going to be replaced then it will not be too massive a job even if you find some, assuming it isn't a huge house? You do not mention wiring, are you sure there is no rubber cabling lurking under the floors?
Sometimes it is hard to tell, we are about to knock down and rebuild a house, we knew next door had been underpinned, however it is on partially infilled land and has an old land/road drain pipe running on the far side of the property which may be cracked so thought it was down to a specific set of issues rather than the geology. When we had the ground survey done our structural engineer was surprised the house had not had major subsidence issues as while there was a good pebble filled sand/clay sub soil under the surface between 0.8 and 1.6m down this turned into wet soft sandy silt. That wiped out the idea to have a basement, the new house is going on piles and a ringbeam.
Kiwi79 said:
Hi Jonesy
We're you inspecting properties? The bit we are looking at is to East of Finchampstead road. I did spot from digging around that a developer wanted a housing development to go up around there but was declined due to amongst various other things the loss of ground to absorb surface water runoff/they also mentioned high water table for the area. We like the house just worried we are buying into a money pit!
More like around Easthampstead Road, so not a million miles away. We're you inspecting properties? The bit we are looking at is to East of Finchampstead road. I did spot from digging around that a developer wanted a housing development to go up around there but was declined due to amongst various other things the loss of ground to absorb surface water runoff/they also mentioned high water table for the area. We like the house just worried we are buying into a money pit!
Where there were problems you could spot them easily enough from the road by just looking for the distortion from the old movement, quite a few places had it to different degrees. Not seen any new movement though.
Can't guarantee there won't be issues but so far of all the building work I've seen being done (lots) none of it has been subsidence repairs.
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