Case Study

Semi-Detached House - Greater London
Introduction - First Visit

DC Structural Services was contacted by the client to view their property after significant cracks started to appear inside and outside part of their home. 


On the initial site visit we noted extensive structural movement to an existing extension on the rear of the property. 

As you can see, the extension had moved away from the house. This particular crack started from beneath the pathway and continued right up to the roof. 

Not only was the crack mirrored internally, but there was also multiple other cracks within the extension area

During our visit we also noted various other cracks and issues resulting from the damage to the extension, most notably damp damage to adjoining rooms. 

Second Visit - Destructive Survey and Soil Investigation

Due to the extensive damage to the property and to help find the route cause of the problem, it was decided that we would come back for a second visit to carry out a soil investigation and destructive survey to the property. This would then be written into a formal Report for the client, detailing our findings, solution and costings.

We found several problems that combined together had resulted in the failure of the extension area;

  1. The extension foundations were at an inadequate depth to support the load of the structure.

  2. The results from the soil investigation showed that the ground was very soft and wet down to a depth of 9.6 metres.

We also found a hidden manhole underneath the french doors, this had undoubtedly contributed to some of the damage caused to the structure. 


We arranged for a CCTV Survey to be carried out, the findings of which showed damage to the waste pipes leading into the manhole.  

Planning & Design 

With all the information we now had to hand, we could provide the client with several different options on how to proceed forward. 

Our client decided to go forward with a total knockdown and rebuild of the extension area, whilst also rectifying the other damage caused to the adjoining rooms and moving the manhole that was discovered to a more suitable location. 

We started to arrange the works with the relevant local authority and utility companies, all of which was dealt with by DC Structural Services Ltd. 

With the relevant permissions granted, works began in January 2020. 

DC Structural Services


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