Garfield-Bennett Building surveying says new advice on how to assess Japanese knotweed should help ensure homeowners aren’t penalised by mortgage lenders should the plant be found on their property. In the UK some homeowners have seen their property prices cut after Japanese knotweed was found, whilst others have been unable to acquire mortgages.
The cross-industry approved advice from the Royal Institution of Chartered Surveyors (RICS) will allow surveyors and banks to accurately assess the risk to a property posed by the damaging plant. Managing Director of Garfield-Bennett Building Surveying, Matthew Garfield-Bennett said there has until now not been any consistent advice on assessing the risk and that has led to some mortgage lenders over-reacting: ‘Jersey’s Environment Department has recently launched an app for people to record sightings of Japanese Knotweed in the island. There is a fear surrounding the plant because it is very invasive and difficult to get rid of, but we must remember that although difficult, it can be brought under control. This new paper allows professionals to use one of the four outlined classifications to measure the extent of the risk and the threat it poses to a property; with tier one being the lowest; when the plant is seven metres or more from the property; and tier four when the plant is within seven metres of habitable space such as conservatories and garages. It also provides treatment advice.’
The RICS paper is supported by the UK Council of Mortgage Lenders and the Building Society Association.
Untreated the extensive and deep root systems of Knotweed will penetrate asphalt and wall foundations, as well as drainage systems. It is easily identifiable but must be disposed of carefully as even very small amounts of cut plant are able to spread.