Property owners must take heed of Court of Appeal ruling on Japanese knotweed, says Joelson.

Daniel Swimer, Head of the Real Estate Litigation team at Joelson, has shared his views on the latest Court of Appeal ruling, Network Rail Infrastructure Limited (Appellant) v Stephen Williams and Robin Waistell (Respondents) [2018] EWCA Civ XXX.

Japanese knotweed can prove very costly for landowners and developers. It can cause structural damages to land developments, block drains, grow between slabs of concrete, disrupt brick paving, and overwhelm outbuildings. It’s also difficult to eradicate. The UK Government has estimated that the cost of eradicating it from the UK stands at £2.6 billion.

In this case, the Court of Appeal has upheld an earlier decision which saw the two respondents receive significant compensation for private nuisance following Network Rail’s inaction over the Japanese knotweed that had encroached on their properties.

Nuisance is the legal term for when a landowner does, or omits to do, something on or with their land, which interferes with the use or enjoyment of neighbouring property, or which causes physical damage to neighbouring property.

The Court of Appeal determined that the affected parties in this case could not succeed in a claim for private nuisance merely because of the diminution in the market value of their properties.

They were entitled however to claim for nuisance caused by the encroachment of the Japanese knotweed because it had reduced their ability to enjoy the amenity and utility of their respective properties.

Sir Terence Etherton, Master of the Rolls, stated that the recorder in the earlier decision was wrong in principle to conclude that the presence of knotweed on Network Rail’s land within seven metres of the claimants’ properties was an actionable nuisance “simply because it diminished the market value of the claimants’ respective properties, because of lender caution in such situations”.

The purpose of the tort of nuisance is not to protect the value of property as an investment or financial asset but to protect the land’s intangible amenity value, specifically the landowners’ ability to fully use and enjoy their properties.

This is an important decision which builds upon a recent spate of cases concerning liability in nuisance for Japanese knotweed.

It should also stand as a warning to developers, landowners and local authorities who fail to treat Japanese knotweed seriously.

They may, however, also welcome this decision as it restricts the basis upon which claims can be brought and may potentially limit the financial compensation awarded by courts in the future.

It is likely that as a result of this appeal other landowners affected by Japanese knotweed will come forward with a view to confronting large scale developments and established housing and commercial property sites.

It is therefore imperative that landowners are constantly vigilant of Japanese knotweed, its roots and rhizomes, as it could impose a serious burden and significant costs on neighbouring landowners wishing to develop their land and or eradicate the weed – costs which could, as a result of this ruling, be passed on to the landowner causing the nuisance.

If you find knotweed on your land, you should arrange for it to be surveyed by a specialist contractor as soon as possible and seek legal advice.

A version of this article appeared on Estate Agent UK Networking, please click here to read this article.

This article is for reference purposes only. It does not constitute legal advice and should not be relied upon as such. Specific legal advice about your specific circumstances should always be sought separately before taking or deciding not to take any action.