Japanese Knotweed can be a nightmare for mortgage purposes. Below are the classification on a Japanese Knotweed Infestation, but ultimately it always boils down to the valuers comments, warranties and ongoing treatment plans. The information below is for guidance only:

• Any classification of 3/4 is an outright decline and even 1&2 can be problematic

• 4= Japanese knotweed is within 7 metres of a habitable space, conservatory and/or garage, either within the boundaries of this property or in a neighbouring property of space; and/or Japanese knotweed is causing serious damage to outbuildings, associated structures, drains, paths, boundary walls and fences and so on. Further investigations by an appropriately qualified and/or experienced person are required. 
• 3 = although Japanese Knotweed is present within the boundaries of the property, it is more than 7 metres of habitable space, conservatory, and/or garage. If there is damage to outbuildings, associated structures; paths and boundary walls and fences, it is minor. Further investigations by an appropriately qualified and/or experienced person are required.
• 2= Japanese knotweed was not seen within the boundaries of this property, but it was seen on neighbouring property or land. Here, it was within 7 metres of the boundary, but more than seven metres away from habitable spaces, conservatory and/or garage of the subject property.
• 1= Japanese Knotweed was not seen on this property, but it can be seen on a neighbouring property, but this can be seen on a neighbouring property or land where it was more than 7 metres away from the boundary.