The Survey

Reports produced with 3 working days of survey completion

A Southwest Survey Knotweed Consists of…

  • We will carry out a detailed survey of your site.
  • Produce a site plan with photographs.
  • Confirm and describe the level of contamination on the site and off the site.
  • The size, location and number of stands, proximity to water, map distances to buildings.
  • We will carry out visual surveys of the adjacent sites to identify potential encroachment.
  • We will advise of the risk of not taking the necessary action to control the plants.
  • We will recommend the most suitable treatment option and programme specifying what materials/herbicides are to be used, when and by what method and the cost.
  • We will produce a survey report with a Management Plan and the costs and time scale associated in treating the Japanese Knotweed
  • Include Guarantee options – 5 year company backed guarantee and 10 year insurance backed guarantees

The costs involved carrying out a survey and producing comprehensive Japanese Knotweed Management Plan are listed below.

The costs

We charge £250 + VAT for a specialist Japanese Knotweed Report (residential properties only up to 1 acre). We normally carry out a Japanese Knotweed Survey and have the report back to you within 3 working days

Please call for commercial surveys.

Once you have received the report and are happy to proceed with the treatment programme, just give Southwest Knotweed a call.

Mortgage lenders risk

The Royal Institute of Chartered Surveyors “RICS” has produced an information paper entitled ‘Japanese Knotweed and Residential Property’.

The RICS has tried to clarify the concerns that lenders have with properties affected by Japanese Knotweed. Many residential mortgage lenders are not keen to lend on properties affected with Japanese Knotweed but may consider applications providing the purchaser or seller can prove that there is a commitment to adequately fund an appropriate treatment programme. The production of a Japanese Knotweed Management Plan based on a survey can establish the level of risk as specified by the RICS table below.

The term ‘habitable space’ refers to those parts of the subject property associated with daily living (including conservatories) and not ancillary spaces (such as outbuildings and/or garages).

According to the Environment Agency’s The Knotweed Code of Practice, Japanese Knotweed rhizomes can extend up to seven metres horizontally and three metres vertically from the last sign of visible surface growth.  This has been used as the minimum distance in the assessment process.

Fig 1: Royal Institute of Chartered Surveyors (RICS) “Risk” table for Japanese Knotweed.




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 or space; and/or Japanese Knotweed is causing serious damage to outbuildings, associated structures, drains, paths, boundary walls and fences and so on.

Further investigations required by an appropriately qualified and/or experienced person


Although Japanese Knotweed is present within the boundaries of the property, it is more than 7 metres from a habitable space, conservatory, and/or garage.


Japanese Knotweed was not seen within the boundaries of this property, but it was seen on a neighbouring property or land. Here, it was within 7 metres of the boundary, but more than 7 metres away from habitable spaces, conservatory and/or garage of the subject property.

1Japanese Knotweed was not seen within the boundaries of this property, but it is present on a neighbouring property or land where it was more than 7 metres away from the boundary.

Unlike some Japanese Knotweed contractors who only offer guarantees covered by their company, we can also offer extra insurance backing by Guaranteed Protection Insurance for a one off additional cost.

Treatment options The guarantee

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