Beautiful trees are an asset to urban environments. But a recent House of Lords decision implies that tree owners may have wider responsibility than previously thought
MOST PEOPLE LIKE BEAUTIFUL TREES NEAR THEIR home. However, tree roots and foundations are not good bedfellows. In times of drought, damage may be caused and claims made.

In Delaware Mansions vs City of Westminster, the House of Lords was faced with such a case. The decision, made late last month, seems to have extended the law in ways that could cause difficulties in future.

Delaware Mansions comprises several blocks of flats in Maida Vale, north-west London. A large London plane tree owned by Westminster council, and under its control, stands in the pavement outside the property.

The original freeholders of the Delaware Mansions were the Church Commissioners. They sold their freehold reversion to Flecksun for the nominal price of £1 in April 1990.

In 1989 there had been a drought, and by the end of that year cracking had developed in the structures of some of the blocks. Shortly before the sale to Flecksun, an engineer reported that the roots of the plane tree were responsible for this damage.

Westminster council was first alerted to the problem in August 1990, some months after the sale. It agreed to prune the tree's roots and also dug a trench next to it, backfilled with PVC to restrict regrowth.

Despite these measures, Flecksun went ahead with extensive piling and underpinning work on the blocks. Evidence of tree roots still under the foundations was found during this work.

Flecksun brought a claim against Westminster to recover its remedial costs. The basis of the claim was the tort of nuisance. The judge found that the roots had desiccated the ground under the foundations and this had caused the cracking. However, he also found that the structural damage had occurred no later than March 1990. In other words, the relevant damage happened prior to Flecksun's taking ownership of the property.

Flecksun had spent the money and it was the claimant. The judge decided that, although the remedial works were proper and reasonable, Flecksun had no cause of action and could not recover its costs.

Will tedious neighbours force owners to cut down trees that have caused no structural damage?

The judge's conclusion seems to reflect the orthodox view that a claim in tort is only possible if the claimant has suffered damage. In this case, of course, the relevant damage had occurred before Flecksun bought the flats.

The Church Commissioners had a cause of action before the sale; but there had been no assignment by them of any right of action against Westminster. It was also acknowledged that the nominal purchase price had not been influenced by the plane tree and the cracking. Flecksun's position was difficult.

Despite this, the House of Lords allowed the appeal and Flecksun was awarded its damages. The reasoning behind this decision is interesting but seems to push the boundaries back a bit.

Although no damage to the structures of the blocks had occurred during Flecksun's ownership, the roots were still dehydrating the soil and inhibiting rehydration. Damage was said by the court to consist of the impairment of the load-bearing qualities of the ground on which Delaware Mansions stood. The House of Lords held that this was a continuing nuisance and that the owners were entitled to abate it with the piling and underpinning work.

The court was at pains to emphasise that there would be no liability for nuisance unless the defendant knew, or ought reasonably to have known, of the nuisance and had unreasonably failed to end it. This had been established by Solloway vs Hampshire County Council and Leakey vs National Trust.

Had Westminster taken down the tree as soon as it was aware of the risk it posed to the flats, it would not have been liable. However, it did not do so and Flecksun was justified in carrying out the works and recovering the costs.

The trouble with this decision is that there must be millions of trees in close proximity to buildings throughout England. Many must have been responsible for impairing the load-bearing qualities of the ground under neighbouring buildings without causing any structural damage.