Expertise: Property Damage
Reasonable foreseeability and private individual owners of domestic property
3 September 2013
1. This morning, Mr Justice Ramsey handed down judgment in Khan and Khan v. (1) London Borough of Harrow; and (2) Helen Sheila Kane, which considered whether tree root subsidence damage was reasonably foreseeable to a private individual owner of a domestic property whose trees caused damage to a neighbouring property.
2. The judgment is required reading for all practitioners handling tree root subsidence claims. It is particularly relevant to insurers claiming against, or defending, private individual owners of domestic properties.
3. Mr and Mrs Khan owned a house in Stanmore, Middlesex. Mrs Kane owned the neighbouring property to the right of the Khans' property.
4. There was a Lawson Cypress hedge on Mrs Kane's property about 10.0m high and 0.5m away from the Khans' house. There was also an oak tree on Mrs Kane's property.
5. Mrs Kane admitted that her Lawson Cypress hedge and oak tree caused and/or contributed to the damage to the Khans' house.
6. However, Mrs Kane asserted that the damage was not reasonably foreseeable to her as an ordinary private individual owner of a domestic property. She also raised breach of duty, contributory negligence, failure to mitigate and points on quantum.
Reasonable Foreseeability – The Law
7. The Judge considered a number of leading authorities on reasonable foreseeability including the Wagon Mound No. 2.
8. The Judge found that the issue of reasonable foreseeability is not a subjective test depending on the peculiar characteristics of the particular defendant but is an objective test as to what ought to have been known to a reasonable person in the position of the defendant. "In this case, the relevant person is a reasonably prudent landowner."
9. A defendant's lack of subjective knowledge cannot lower the standard. However, a defendant's subjective knowledge can impose a higher standard. The Judge found:
"In my judgment, the purpose of the standard being set by the knowledge imputed to a class of persons is to impose a higher standard on persons in that class. It therefore creates a floor but not a ceiling on the level of knowledge so that subjective knowledge can raise the standard. However, lack of actual knowledge cannot lower the standard or exclude liability which would be imposed based on the standard generally imposed."
Reasonable Foreseeability - The Decision
10. The Judge found on the facts that Mrs Kane did not have actual subjective knowledge about the risk of damage to the Khans' property from her trees.
11. However, on a close analysis of the facts, he found that a reasonably prudent landowner would have been aware of the real risk of damage from the Lawson Cypress hedge but not the oak tree.
12. So, the Judge gave judgment for the Claimant for the damage caused by the Lawson Cypress hedge.
13. This important decision is significant for private individual owners of domestic properties and their insurers.
14. In part, because of the ABI Domestic Subsidence Agreement, cases against private individual owners of domestic properties do not frequently come before the Courts.
15. Further, a misconception has developed that, if a private individual owner of a domestic property can assert that she does not have actual subjective knowledge of the risk of tree root subsidence damage from her trees (or generally), she is then immune from claims against her for such damage caused by her trees.
16. This judgment makes clear that the starting part is the objective test of what would be reasonably foreseeable to a reasonably prudent landowner in the Defendant's position.
17. Thus, liability for tree root subsidence damage can be established against a private individual owner of domestic property despite the individual’s lack of actual subjective knowledge of the risk.
Daniel Crowley of 2 Temple Gardens acted for the successful Claimants instructed by Kennedys.
 The claim against LB Harrow who owned land to the left of the Khans' property was settled before trial.
DANIEL CROWLEY FCIArb