Japanese Knotweed and residential property
Published January 2022
Effective from March 2022
This guidance note is an update to the RICS information paper published in 2012, responding to a House of Commons Science and Technology Committee report and a Department of Environment, Food and Rural Affairs (Defra) investigation into Japanese knotweed questioning the current approach to the assessment of risk, and by extension, impact on value, of Japanese knotweed on the built environment.
The purpose of this updated guidance note is to address both the findings and provide guidance based on market informed industry best practice, the most recent research about a more holistic assessment of Japanese knotweed, to ensure RICS members provide the best advice to users of valuation and condition reports.
This document contains a decision tree based on risk level to help valuers determine the appropriate management approach needed for Japanese knotweed. The new process still delivers a straightforward and objective categorisation of Japanese knotweed infestations because this provides the clarity that is essential for lenders and which will continue to ensure confidence and trust among the wider stakeholders.