RICS has just released its long-awaited guidance for surveyors on Japanese knotweed, with the apparent intention to limit the effect it has on the property market.

McBride Polly

Polly McBride

The guidance moves away from the application of the seven-metre rule, focusing instead on the impact on amenity space. This is welcome news for surveyors.

The guidance clarifies a number of points. In future, only if knotweed is ‘clearly visible’ will identification be expected; there will be no need to carry out a plant-by-plant check. The report recognises the potential difficulties of inspecting for knotweed, for example if vegetation is dense or boundaries are unclear, and acknowledges that a competent surveyor might still not identify knotweed if, for instance, the growth is too small or difficult to see, it has been cleared or the inspection is undertaken at a time of year when the plant is dormant.

We anticipate that this will help to stem the flow of claims against surveyors that have been brought on the basis that Japanese knotweed has been found at a property but where no thought has been given as to whether it should have been spotted by a surveyor.

RICS has produced a flow-chart to assist surveyors with their assessment of Japanese knotweed, which leads to four ‘management categories’.

The new position is simple: if the knotweed is on site and not causing any visible damage to a structure, then the question is whether it is likely to prevent use of or restrict access to amenity space. If it does, category B applies and the position is largely as it has been to date. If it does not (category C), no further action is required.

This distinction is important to surveyors because it may limit the damages a claimant can recover; while there is still likely to be a residual diminution of value in category B, any effect on value for category C Japanese knotweed is likely to be limited to the cost of remediation. This is a significant departure from the previous approach and we anticipate that potential claimants may be deterred from bringing claims in some circumstances.

In summary, the guidance is a welcome step in the right direction, which may help limit the number of ‘opportunistic’ claims against surveyors and also, hopefully, speed up resolution of the more meritorious claims, both of which would be of great benefit to surveyors and their insurers.

Polly McBride is a legal director at law firm DAC Beachcroft