Homeowner wins £300k court battle against local council over Japanese knotweed

A street in the village of Nant-y-moel
The homeowner lives in Nant-y-moel in Wales (Image credit: Google Street View)

A homeowner has won a £300,000 court case after suing his local authority for letting Japanese knotweed spread into his garden.

Marc Davies, 38, took Bridgend County Borough Council in south Wales to court after the invasive weed spread from a disused railway line next to his home.

It comes soon after a furniture designer successfully sued the previous owner of his south west London home for £200,000 after finding Japanese knotweed behind the garden shed.

What is Japanese knotweed?

Japanese knotweed (Fallopia japonica) was introduced to the UK during the Victorian era and gardeners were attracted to its heart-shaped leaves and exotic flowers, but the plant grows aggressively and its extensive root system can cause damage to buildings and roads.

Japanese knotweed removal is tricky and preventing its return can be an intensive and expensive job– it has been known for banks to refuse mortgage applications on houses with an infestation.

It's also worth checking out our guide on 'how to kill Japanese Knotweed'. 

Japanese knotweed

Japanese knotweed has heart-shaped leaves (Image credit: Getty)

Why did the homeowner sue the local council?

Mr Davies bought the house in the village of Nant-y-moel in 2004 but did not realise the plants, which grew at a “phenomenal rate”, on neighbouring council land were knotweed.

Mr Davies said the knotweed reduced the value of his terraced house because he could not landscape the garden or build a shed because of the extensive roots, known as rhizomes, beneath his home.

He won an initial case but was denied after two judges said the law did not allow knotweed 'nuisance' damages to be paid for 'pure economic loss', reports the Daily Mail.

The engineer appealed and won after senior judges confirmed the right of homeowners to claim damages for lost value after knotweed comes in from a neighbouring property.

How much was the homeowner awarded by the judge?

The homeowner was awarded £4,900 but the case will cost the council about £300,000 in lawyers' bills.

The damages claim was based on the 'residual diminution' in value of his property, or the reduction in value even after the invasion had been treated.

However, the court fight could pave the way for millions more to be paid out to victims as it sets a precedent.

Why was the council liable?

Judge Andrew Fouracre, speaking at the county court, said the knotweed had probably been on the council land for more than half a century and had spread into Mr Davies' property before he moved in.

Mr Davies’ lawyer Tom Carter said: “When selling your home, you have to declare whether it is affected by Japanese knotweed.

“If the Court of Appeal had decided against the claimant, it would have meant that hundreds of homeowners would have no remedy when buyers pulled out or made reduced offers and they would be left out of pocket.”

Earlier this month knotweed hit the headlines when Jonathan Downing sued the previous owner of his £700,000 property in Raynes Park, south west London after discovering knotweed in his garden.

Mr Downing sued for damages, claiming the former owner misrepresented whether there was knotweed at the property during the sale.

Judge Jan Luba KC ruled Mr Henderson should pay £200,000 in costs and damages after finding he did not genuinely believe the seller's story that he did not know the property was affected by knotweed at the time of sale.

Sam Webb

Sam is based in Coventry and has been a news reporter for nearly 20 years. His work has featured in the Mirror, The Sun, MailOnline, the Independent, and news outlets throughout the world.  As a copywriter, he has written for clients as diverse as Saint-Gobain, Michelin, Halfords Autocentre, Great British Heating, and Irwin Industrial Tools. During the pandemic, he converted a van into a mini-camper and is currently planning to convert his shed into an office and Star Wars shrine.