News and Events

What is Japanese Knotweed?

  • Posted

Japanese knotweed can be found almost all over the country. The uncontrolled and invasive nature quickly allowed it to become a pest in the UK. In the winter the plant dies back to ground level but by early summer the bamboo-like stems emerge deep underground to shoot over 2.1m (7ft) supressing all other plant growth. The roots and shoots are capable of exploiting gaps in buildings and hard surfaces such as concrete and tarmac.

Legal Framework

The key legislation dealing with Japanese knotweed is the Wildlife and Countryside Act 1981 which makes it an offence to plant or otherwise cause Japanese Knotweed to grow in the wild. Penalties for offences committed after 12th March 2015 are six months imprisonment and unlimited fines.  

The Environmental Protection Act 1990 imposes a duty of care on people dealing with material containing viable knotweed to take reasonable steps to ensure it is handled and disposed effectively.

The presence of Japanese knotweed can also result in potential civil liability. A neighbour can bring a common law claim against the landlord or tenant if Japanese knotweed causes loss of enjoyment or damage to their land. Furthermore, having Japanese Knotweed growing within seven metres of a built structure of neighbouring land has been held to be an actionable private nuisance. In such circumstances you may be asked to enter into a Japanese knotweed plan and make a payment on account. Smith & Anor v Line (COOTR216) 2018.

Implications of Japanese Knotweed

The spread of Japanese Knotweed can adversely affect the value, marketability and insurance of land. Lenders may also refuse to lend on properties which are affected. There is a general reluctance to lend on properties affected by Japanese Knotweed, although some lenders are willing to consider it on a case-by-case basis. Lenders will generally accept scenarios where there is an approved Japanese Knotweed mitigation plan in place even if those works are on-going provided the works are backed by a ten year insurance backed guarantee and undertaken by a recognised professional. The costs of a Japanese treatment plan can range from £4,000 to £20,000 depending on the size of the treatment area.

Pre-Exchange Enquiries

The rule of ‘Caveat Emptor’ will apply which means the seller has no duty to volunteer information concerning the physical condition of the property and it is the buyer’s responsibility to satisfy themselves as to the condition of the property by inspection and research. At Emery Johnson Astills we will carefully consider the Property Information Form (TA6) filled out by the sellers and raise the necessary enquiries if the seller indicates the presence of Japanese Knotweed. While the seller will be liable for misrepresentation on the TA6 we will always advise all potential buyers to physically inspect the property and obtain a survey.

What can landowners or purchasers do?

  • Obtain a Japanese Knotweed search report
  • Employ the services of an invasive weeds professional
  • Obtain images of suspected Japanese Knotweed infestation for validation by a professional expert
  • Request details of any previous works undertaken to address Japanese Knotweed infestation including details of any insurance-backed guarantee solution that may be valid
  • Consider contractual negotiation based on report findings.

Our Emery Johnson Astills Conveyancing Team in Leicester and Loughborough are happy to assist if you are buying or selling a house.

If you require assistance or further information, please contact our Emery Johnson Astills Conveyancing Team on 0116 2554 855 (Leicester) or 01509 610 312 (Loughborough).