Concerns about trees or large walls that are moving and changing shape

SWJ Consulting is proud to do a lot of work for the Oxford Diocese Academy Trust who is responsible for Burford Primary School in the Cotswolds.

Behind/adjacent to the primary school is a residential plot where the owners had built a summer house that was close to the school’s 3.5m high stone wall and sat under the canopy of a large silver birch tree.

The birch tree was causing problems for the residents with leaves blocking up their guttering etc. and there were concerns that it was causing the stone wall to move and bulge towards the summer house. The tree was removed to see if this was causing the wall to move, but in reality, it was not the tree causing the issue. Unfortunately, the wall had suffered a legacy of unsympathetic repairs which was the cause of the problem, not the tree.

Where several cracks had developed in the wall over the years they had been repaired with cementitious mortar. The issue is that cementitious mortar is nowhere near as flexible as the rest of the wall which is bound together with lime mortar on shallow foundations and is exposed to the elements. There was therefore a conflict between the cyclical movement of the wall and the inflexible nature of the repair. Lime mortar does quickly weather and needs maintenance and so although cement seems the more robust solution it’s counterproductive as the repair will fail because it’s unsuitable.

Project Team

Client: Burford Primary School

Contractor: Oxford Diocesan Schools Trust 

We have monitored the wall over several months and demonstrated the movement is cyclical – the bulge is entirely historic and is not an ongoing concern.  

If you have concerns about trees or large walls that are moving and changing shape please give us a call on 01993 225085 or email mail@swjconsulting.co.uk. We have experience and expertise, especially in the Cotswold, with old and listed properties and their boundaries as well as extensive local knowledge of the ground which helps when it comes to deciding on the risks trees pose to buildings and foundations.