The invasive plant threatens millions of pounds’ worth of property transactions every year, and with the property market under strain to close deals ahead of the stamp duty holiday, warnings are being issued to home buyers and property professionals.
Japanese knotweed, an aggressive plant brought to England in the Victorian era, grows rapidly and has the potential to destroy man-made and natural structures in its path. It is able to grow through cracks in concrete and undermine the structural integrity of buildings and homes, and is estimated to be present in every 10km2 of the British Isles.
The plant lies dormant in winter but it is in spring when the first signs of Japanese knotweed growth appears – worryingly close to the June deadline for completion. The plant’s distinctive red and purple shoots are often accompanied by rolled back leaves that grow rapidly from the stored nutrients in the rhizome.
A 2020 KnowledgeBank study on lenders’ attitudes to Japanese knotweed prepared for a Defra report revealed that only 3% of lenders were willing to provide a mortgage on residential properties with Japanese knotweed present. A further 38% were willing to lend subject to certain conditions, while 39% declared knotweed unacceptable and were unwilling to lend if Japanese knotweed was present.
Partner and Head of Residential Property at Slater Heelis, Zara Banday outlined the legal position, “The responsibility lies with the sellers to complete a Property Information Form (TA6). Failure to report it or deliberately conceal Japanese knotweed could lead to sellers being sued for misrepresentation and liable for compensation.
“The danger is that in a bid to secure a property ahead of the stamp duty holiday deadline, buyers don’t carry out the proper due diligence. Overlooking issues like knotweed could lead to delays, deals falling through or huge costs further down the line.
“I recently dealt with a client who had a mortgage offer withdrawn after knotweed was discovered by her surveyor on the boundary of a disused farm bordering the property. It was her dream home and having already spent over a thousand pounds in fees, she pushed ahead with the sale. A remediation firm with an insurance-backed guarantee had to be appointed to enable her to secure a mortgage and purchase the house.
“The discovery put the whole purchase in jeopardy and delayed the transaction by weeks.
“My advice would be to view a property a number of times, check the boundary plan carefully, and liaise very closely with your surveyors so that issues like knotweed are spotted at the earliest opportunity. Ultimately, buyers need to be much more prudent on what is likely to be the biggest purchase of their life.”
David Layland, founding member of the Invasive Non-Native Species Association and joint MD of Japanese Knotweed Control – one of the UK’s first specialist remediation companies – said, “If knotweed is present on the land, it does not necessarily have to affect a sale. Having a proper remediation strategy in place with robust warranties and insurance can help demonstrate to solicitors, conveyancers and mortgage lenders that the knotweed issue is under control.”
Chris Ridehalgh, director at Organic Money, outlined the view from an insurance perspective, “We would always recommend carrying out a comprehensive inspection of the property before purchase. Presence of Japanese knotweed should not lead to a home insurance refusal.
“Most insurance policies will not cover you for the treatment of knotweed; however, subsidence or damage caused to the property could be covered. Homeowners should be aware that failure to deal with Japanese knotweed could void any claims for building damage as well as leaving them exposed to a liability claim from a neighbouring property.”