Tree root subsidence

Subsidence occurs when the soil beneath a building is unstable and sinks downward. This is not the same as ‘settlement’, which is caused by the weight of the building, but it can still have a negative impact in terms of the overall structural stability. The opposite effect of subsidence is ‘heave’, where the site upon which the building is situated moves upwards and/or sideways.

Burge v South Gloucestershire Council:

In a ground-breaking decision of interest to property professionals and homeowners, a couple whose conservatory was catastrophically undermined by the roots of a protected oak tree have won £25,000 in compensation from their local council.

The tree, which was protected by a tree preservation order (TPO), reached a height of up to 11 m and stood just outside the couple’s garden, about 13 m from their home. Expert evidence pointed to it as the cause of severe cracking in the couple’s conservatory but the council had refused to allow it to be felled because of the impact that would have on the area’s visual amenity.

The couple sought compensation under Section 203 of the Town and Country Planning Act 1990 after the conservatory had to be demolished and rebuilt. In resisting the claim, however, the council argued that the conservatory had not been constructed in accordance with building industry standards.

Its foundations were extremely shallow and, had it been more solidly built, it would have been better able to resist the pressure of the tree roots. In the circumstances, it was submitted that an award to the couple could open the floodgates to a barrage of similar claims against local authorities in respect of shoddily built structures affected by tree roots.

In upholding the couple’s claim, however, the Upper Tribunal ruled that the damage to the conservatory was reasonably foreseeable. The couple had been perfectly entitled to put their trust in professional contractors they employed to construct the conservatory. It would not have been damaged had it not been for the council’s refusal to permit felling of the oak.

The council was ordered to pay £25,000 in compensation, plus the legal costs of the case.

--Rex Cowell Solicitors

[edit] Related articles on Designing Buildings Wiki

• Buttress root.
• Ground heave.
• Property disrepair and landlord liabilities.
• Subsidence.
• Tree dripline.
• Tree hazard survey.
• Tree preservation order TPO.
• Tree rights.