Survey didn't identify a non standard building materials

birdbob

We had a structural survey from a reputable firm when we bought our house 4 years ago. It identified that the house was probably constructed of stone and rubble and apart from a few minor recommendations was a non problematic survey. We have now put our house on the market and had accepted an offer. The buyers surveyor advised that at least part of the house is constructed from Cob. As a result the buyer withdrew from the purchase, worried about potential future repair issues. The house is rendered with cement which isn't unusual in the area although it is recommended that lime render be used if re-rendering. The fact that the original survey didn't identify possible cob in the construction has clearly affected the marketability of the property and potentially could lead to increased repair bills if problems develop with the structure - eg water penetration could in a worst case lead to wall collapse. The cost of lime rendering would be around £30k. My question is do i have any redress to the original surveyors for not at least advising that cob in the walls was a possibility which would have allowed us to make further enquiries when initially purchasing the property?

user1977

If you can demonstrate that they ought to have spotted it, yes. 

Robin9

You could amend the sale particulars to include "partly constructed in Cob"   - may even be a selling point to the right buyer.

mebu60

Might be worth asking latest surveyor how they identified the cob and what level of survey was being undertaken. If it was same (or lower) than yours and the identification of the cob was pretty straightforward then it gives you some initial ammunition. If your surveyor said 'probably' as quoted by you above with sufficient caveats it may be tricky to prove negligence.

Hoenir

birdbob said:

The fact that the original survey didn't identify possible cob in the construction has clearly affected the marketability of the property 

On the basis that one buyer has baulked and walked away ? Cob is a centuries old method of construction. As you've noted many properties in the area use an alternative to line rendering down to the cost. Comes with the ownership of such properties. In the same way that a thatch roof has  limited lifespan. 

theartfullodger

Cob could well have been standard when 1st built. My SiL has a mainly Cob thatched cottage. 

TheJP

Are you certain you had a structual survey and not a level 2/home buyers survey? There is a difference in what they look for, unless the surveyor took samples it would be hard to 100% confirm what the property build is.

FreeBear

https://www.bbc.co.uk/news/uk-england-devon-36926950

And a follow-up of the same house - https://www.desmondeassociates.co.uk/news/cob-building-collapse-devon

Cement renders should never be used on a cob wall. Water can get behind the render and do untold damage. The first you know is when the wall fails. Unfortunately, unless you are familiar with the building, it is impossible to say for certain what is behind a render without some destructive investigation. With a familiarity and in the absence of testing, you can only give an opinion.

birdbob

Great comments thanks everyone. Im probably just nervous as one buyer got cold feet but just wanted to get some second opinions in case i was missing something. As you say its very difficult to establish the building materials behind the render but some internal work we had done indicates probably stone on gables and to first floor height but at least some cob above that but that was well after the survey so probably difficult to prove. We have a cement render and on inspection by our builder last year when he painted the exterior seems watertight at the moment. Replacing it with lime would be very expensive and there seems to be split opinion on the "never use cement render on cob" argument- there are people nearby who have cement render and say their house is very dry, they just make sure they maintain it very well and the render has been on for at least 40 years. There are people with lime render who have to constantly use dehumidifyers as the house has high humidity (even with heating) but I accept they are probably safer from any major wall problems with water ingress. A lime specialist admitted that a new cement render should provide adequate protection but older renders have the risks stated. As my render seems watertight i have been advised by my local builder who knows these types of buildings to leave it alone until it shows signs of needing replacing.

Havanese

birdbob said:

We had a structural survey from a reputable firm when we bought our house 4 years ago. It identified that the house was probably constructed of stone and rubble and apart from a few minor recommendations was a non problematic survey. We have now put our house on the market and had accepted an offer. The buyers surveyor advised that at least part of the house is constructed from Cob. As a result the buyer withdrew from the purchase, worried about potential future repair issues. The house is rendered with cement which isn't unusual in the area although it is recommended that lime render be used if re-rendering. The fact that the original survey didn't identify possible cob in the construction has clearly affected the marketability of the property and potentially could lead to increased repair bills if problems develop with the structure - eg water penetration could in a worst case lead to wall collapse. The cost of lime rendering would be around £30k. My question is do i have any redress to the original surveyors for not at least advising that cob in the walls was a possibility which would have allowed us to make further enquiries when initially purchasing the property?

Hi,

Did you resolve this issue? 
Not sure if you are aware, but surveyors are potentially liable for six years post survey. They have to have cover in case of eventualities like yours.
Currently going through similar.
Would love to share experiences and advice..