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A homeowner in Leeds, UK contacted Geobear to discuss an issue with an extension built onto the side of their property.

The one storey extension was built on standard raft foundations adjacent to the perimeter wall of the house. After a number of years small cracks started to appear on the internal walls where the extension met the original property. Further inspection to exterior walls clearly indicated the extension was rotating away from the property.

Rotation is the term used when and extension or conservatory sinks slightly and pulls away from the main structure, almost like a hinge effect where one side sinks and the entire extended structure moves away from the join.

This problem is common for extensions and conservatories that begin to sink, the causes could be tree roots sucking moisture from the soils, poor drainage or insufficient foundations. But whichever issue it is, Geobear’s geopolymer injection can rectify the problem and under the right conditions move the structure back.

Customer Alternatives

On this property the alternatives would include either underpinning the extension or installation of mini piles. Both of these solutions are very long winded and would have involved weeks of inconvenience to the homeowner. These processes would involve major excavation of the garden adjacent to the structure and leave the owners property looking like a construction site.

Why Geobear?

Comparatively, the Geobear solution is many times faster than underpinning or piling. On this property we could stabilise the extension within two days, which in both direct cost to the customer and in terms of the inconvenience made our solution far more attractive.

crack in wall

Subsidence crack

The solution Geobear provided was to inject our geopolymer at 1 metre centres around the perimeter wall of the extension. Our material is installed through drilled injection holes meaning minimal disruption to the area. The material is injected to a depth of 2 metres and expands to fill the micro voids in the soil and strengthen it to prevent movement. In this instance the extension was lifted which helped to close the visible cracks.

Customer testimonial

“Often we only hear negatives about projects that are completed, but on this occasion, I can only say that I have praise for your office and on-site team

Your on-site team gave me confidence from the first phone call saying they had delays due to an accident on the motorway, this may not seem important to many but it is the confirmation that customers are important, this approach continued throughout the job.

It was identified that I was interested in the procedure and at each stage they explained fully, this was done in a very professional way and at no time did I feel this was in any way patronising.

As a team of guys I can only praise them, each had a full awareness of the process and what was required, very little talking just a focus on the job in hand, this adding to the confidence given to ourselves. As a founding director of two companies I see these guys are an asset to Geobear.”



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We deliver projects on any sort of building or structure – from conservatory extension problems to 80,000m2 warehouses and road infrastructure. In most cases we will have the best solution, so get in touch today.

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