RICS scraps Japanese Knotweed seven-meter rule

fallopia japonica or japanese knotweed. branch with green leaves and white flowers


RICS has published new guidance on the assessment of Japanese Knotweed by valuation surveyors. It scraps the seven-meter rule introduced in previous guidance as the measure of the danger the plant posed to property.

The new guidance came into force on 23 March 2022, following a consultation (see Brunel News December 2021) and follows academic guidance which found the danger of Japanese Knotweed had been overstated. The guidance sets out three levels of risk that surveyors should consider when Knotweed is seen within the boundaries of a property.

Management category ‘A’ means the plant is causing damage to a structure, while category ‘B’ means that Knotweed may be likely to prevent use of amenity space. Category ‘C’ means that Knotweed is present but is not damaging the property or affecting amenity.

Mortgage lenders are expected to impose restriction on lending for categories A and B, where remediation work may be required, but not for category C.
A further category ‘D’ is used to assess the risk of Knotweed from neighbouring properties, which reduces the distance that infestation must be reported to lenders from seven to three meters.

The author of the guidance, Philip Santo, wrote that the revised approach “replaces the crude distance-based measure by reflecting the actual impact of an infestation at a property.”

James Burgoyne of Brunel Professions welcomed the new guidance: “Over the years many valuation surveyors have faced negligence claims alleging sizeable losses resulting from the presence of Knotweed. This new guidance will provide a far better assessment of the danger Knotweed poses in specific cases.”

RICS has published the Guidance Note and an article about the guidance on its website. Reports about the development have been published by Property Industry Eye, The Telegraph and Beale Law.

Professionalindemnity.com is owned by Brunel Professions, which is a leading professional indemnity insurance broker in the UK. Click here to get a quote or call 0345 450 1074 to speak to a broker.