subsidence garden help

vicstick86

Hi. We've recently sold our house stc.
The buyer has got back to the estate agent, saying the surveyor has suggested an engineers report as there is possible subsidence in the front garden.
I'm a little confused as to what they are saying about this... as we live on a very steeply sloping site. With about 40 steps up to the front door. The garden is on a large slope just grass and soil going to a retaining wall. The retaining wall needs repairing but is still in place.
We received a letter saying about possible subsidence in the garden, then asking us if we had any issues of subsidence... the house is fine. We had a survey done in 2009, and the surveryor found no cause for concern. The house is also in a block of four terraces, and there are no subsidence issues with any of them
I'm just really confused to why they need an engineer to look at a garden....are they suggesting if the gardens slipped then the house will too? I'm thinkin of asking to see the survey, but that's not usual practice is it? Any help ideas gratefully received as I'm beside myself with worry at the mention of subsidence.

dacouch

Are they talking about subsidence eg the house or garden walls moving or landslip eg the land moving.

Bear in mind that the majority of Building Insurance Policies will only cover subsidence / landslip to the garden wall or garden if the main house is also affected.

ValHaller

Have you sold it? Contracts exchanged? Or have you only accepted an offer? And from whom is the letter?

On the face of it, I would say that the retaining wall is probably the problem - and in passing the information along it has become exaggerated either innocently or as part of a pitch to negotiate the price down.

vicstick86

Yeah that's what's confusing me really. The letter says about subsidence in the front garden.. and the land has slipped a bit, but if you imagine just a small slope in all the rain weve had, the soils moved a little bit down the garden , as its so steep, but its not all at the bottom its still sloped and the walls still supporting it...The wall needs either rebuilding or supporting at some point, But it's more of a job for a landscaper or builder not a structural engineers. To be honest we only noticed the wall needs sorting when the surveyor mentioned it, if we were staying we would have just paid for it ourselves, not worth an insurance claim!
BUT.. the next part of the letter is asking us a issues of subsidence with us, or previous owners, so I guess that relates to the house.
Apparently the surveyors told them to progress no further with the buy until they've had the report, and my feeling is they wouldn't say this over a slipping garden.

vicstick86

Sorry and in answer to your questions... just accepted an offer,, but this was a few mddonths ago, and the letter is from the buyers solicitor...

dacouch

vicstick86 wrote: »

Yeah that's what's confusing me really. The letter says about subsidence in the front garden.. and the land has slipped a bit, but if you imagine just a small slope in all the rain weve had, the soils moved a little bit down the garden , as its so steep, but its not all at the bottom its still sloped and the walls still supporting it...The wall needs either rebuilding or supporting at some point, But it's more of a job for a landscaper or builder not a structural engineers. To be honest we only noticed the wall needs sorting when the surveyor mentioned it, if we were staying we would have just paid for it ourselves, not worth an insurance claim!
BUT.. the next part of the letter is asking us a issues of subsidence with us, or previous owners, so I guess that relates to the house.
Apparently the surveyors told them to progress no further with the buy until they've had the report, and my feeling is they wouldn't say this over a slipping garden.

This can often be cured or reduced by putting a low wall part way up the sloping garden, as you say a good landscape gardener could handle it.

Furts

vicstick86 wrote: »

Yeah that's what's confusing me really. The letter says about subsidence in the front garden.. and the land has slipped a bit, but if you imagine just a small slope in all the rain weve had, the soils moved a little bit down the garden , as its so steep, but its not all at the bottom its still sloped and the walls still supporting it...The wall needs either rebuilding or supporting at some point, But it's more of a job for a landscaper or builder not a structural engineers. To be honest we only noticed the wall needs sorting when the surveyor mentioned it, if we were staying we would have just paid for it ourselves, not worth an insurance claim!
BUT.. the next part of the letter is asking us a issues of subsidence with us, or previous owners, so I guess that relates to the house.
Apparently the surveyors told them to progress no further with the buy until they've had the report, and my feeling is they wouldn't say this over a slipping garden.

How old is the retaining wall and has it been built and maintained correctly?

All retaining walls should be designed, even if the design is taken from guidelines. It is not correct to say this is a job for a land scape gardener - though they could build one to a design This will be why a structural engineer is involved.

Many people are unaware of the significant loadings on a retaining wall, which in your case you have admitted is not in good order. If you think of a metre cube of clay, this weighs approx two tonnes. How much is piled up in your garden, then possibly moving, and held by a retaining wall may be suspect? What would happen if the wall suddenly failed?

chris_m

Furts wrote: »

Many people are unaware of the significant loadings on a retaining wall, which in your case you have admitted is not in good order. If you think of a metre cube of clay, this weighs approx two tonnes. How much is piled up in your garden, then possibly moving, and held by a retaining wall may be suspect? What would happen if the wall suddenly failed?

Possibly something like this;
http://www.bbc.co.uk/news/uk-wales-north-east-wales-19701747

Granted, that wall hadn't been built properly and also had too much soil backfilled behind it but if the OPs garden is working its way downhill what is/was an adequate retaining wall could easily become inadequate due to the increased loading beyond that for which it was designed .