The Court can see the wood from the trees!
In an important case for practitioners and insurers, the Court has made clear when a homeowner will be liable for tree root damage to another property Mr and Mrs Khan own a house in Stanmore, Middlesex. Mrs Kane owns the house next door and the roots of 2 of the trees in Mrs Kane’s garden caused subsidence damage to the Khan’s house. However, Mrs Kane denied any liability for the damage upon the basis she did not know of the risk of such damage and acted promptly to deal with the trees once she was so aware.
One of the trees was a 10 metre high Lawson Cypress hedge that was right next to the boundary and the other was an oak tree somewhat further away from the Khan’s house. Both were felled when it became apparent to Mrs Kane that they were responsible for causing damage to her neighbours.
The law provides that a homeowner will be liable in negligence and/or nuisance for damage caused by their tree roots where such damage was reasonably foreseeable. The Khans claimed that, even though Mrs Kane had no knowledge of the risk, such damage was reasonably foreseeable as it was common knowledge that tree roots can cause damage and this was particularly the case where, as here, the houses were built on clay sub-soils.
The Court had to decide what was the correct test for reasonable foreseeability of tree root damage. Should it be based on the actual knowledge of the owner of the trees or should it be based on an objective test based on what a homeowner would usually know?
The Court accepted that Mrs Kane had no actual knowledge of the risk from tree roots from the media or otherwise and that her gardener had never mentioned this to her.
After considering previous case authorities, the Court held that liability cannot be avoided because of the actual knowledge and particular characteristics of the Defendant homeowner. Liability has to be based on what knowledge is reasonably to be expected of a reasonably prudent homeowner.
Whilst ignorance of the risk of tree roots is therefore no defence in itself, actual knowledge of the risk can raise the standard in determining liability. Accordingly, if a homeowner is particularly familiar with the risk (for example, if they were a surveyor or engineer or had previous experience) then a higher standard will apply if the damage is claimed not to have been foreseeable.
In deciding what standard should apply, the Court took account of the widespread media coverage there has been of tree-related subsidence on clay soils and of the need for insurance to cover this risk. However, knowledge of the general risk is not enough to make a homeowner liable. There has to be a particular risk the homeowner should have been aware of and dealt with earlier.
In this case, the Court held that the height, poor condition and location of the Cypress hedge was a clear risk to the adjoining house that should have been appreciated. However, the location and condition of the oak tree gave no cause for any particular concern and, in fact, it was not initially identified by the experts as being responsible for any damage.
Accordingly, Mrs Khan was liable for damages resulting from the Cypress hedge even though she had no knowledge of the risk before being put on notice about it. However, her liability was reduced by 15% because Mr and Mrs Khan should have told her earlier about the risk and damage suffered.