Japanese Knotweed Survey

Japanese Knotweed surveys are essential for several reasons. Firstly, they help property owners identify the presence and extent of Japanese Knotweed infestation on their land, which is crucial for effective management.

Early detection allows for prompt action to prevent further spread and minimise damage to structures and ecosystems. Additionally, many mortgage lenders and insurance companies require evidence of a Japanese Knotweed survey before approving loans or coverage, highlighting its importance in property transactions and legal compliance.

Japanese Knotweed is classified as a controlled plant under the Wildlife and Countryside Act 1981 in the UK. It is illegal to allow Japanese Knotweed to spread into the wild or onto neighbouring properties.

Property owners have a legal obligation to prevent the spread of Japanese Knotweed from their land, and failure to do so can result in enforcement action, fines, or legal disputes. Understanding and complying with these legal requirements is essential for all property owners.

The price of a Japanese Knotweed survey can fluctuate based on various factors, such as the property’s size and the extent of the infestation. Typically, our Japanese Knotweed survey services start from £150 + VAT. However, if you opt for our Knotweed Management Plan, in some cases the survey fee can be subtracted from the total cost of your treatment plan.

While Japanese Knotweed is not directly harmful to humans, it can pose significant risks to properties, infrastructure and ecosystems. Its rapid growth and expansive root system can cause structural damage to buildings, roads and drainage systems, leading to costly repairs and maintenance.

Additionally, Japanese Knotweed can outcompete native vegetation, disrupting local ecosystems and reducing biodiversity. While the plant itself may not be dangerous, its presence can have far-reaching consequences for both the environment and property owners.

Obtaining a mortgage on a property affected by Japanese Knotweed can be challenging, as many mortgage lenders have strict criteria regarding the presence of invasive plants. Most lenders require evidence of a Japanese Knotweed Management Plan (KMP) and assurance that the infestation is under control before approving a loan.

Some lenders may refuse mortgages altogether if Japanese Knotweed is present on the property, while others may require additional surveys or specialist reports to assess the risk. It’s important for buyers and sellers to disclose any known Japanese Knotweed infestations during property transactions to avoid delays or complications.

Building on land with Japanese Knotweed present can be challenging due to the risks associated with the plant’s aggressive root system. Japanese Knotweed roots can penetrate through hard surfaces like concrete and asphalt, potentially causing structural damage to buildings, roads and other infrastructure.

Therefore, it’s essential to address any Japanese Knotweed infestation before proceeding with construction to mitigate these risks effectively.

While there is no legal requirement to report Japanese Knotweed on your property, it’s important to manage and control its spread responsibly.

Ignoring Japanese Knotweed can lead to severe consequences, including property damage, legal disputes with neighbours and difficulty selling or buying affected properties. Therefore, it’s advisable to address Japanese Knotweed infestations promptly and seek professional assistance for effective management and eradication.

The updated RICS Guidance Note since March 2022 establishes three distinct categories for assessing Japanese Knotweed on residential properties:

• Management Category A: Action is necessary when Japanese Knotweed is identified and is visibly damaging significant structures on-site. This can have a notable impact on property value due to the incurred costs of repair and remediation.
• Management Category B: Action is warranted when there is no structural damage caused by Japanese Knotweed, but its presence is likely to hinder the use of or restrict access to amenity space. While this may affect property value, the focus lies on the expenses associated with remediation without requiring structural repairs.
• Management Category C: Survey indicates the presence of Japanese Knotweed without causing damage to structures or impacting amenities. Here, the effect on property value is minimal since structures and amenities remain unaffected, and any remediation expenses are at the discretion of the property owner.

For properties falling under Management Categories A or B, lenders typically implement retentions on mortgage advances until they receive a report from a remediation specialist. However, for properties categorised as Management Category C, lenders generally do not impose retentions since the infestation hasn’t directly impacted the property’s structures or amenities.

Also, if Japanese Knotweed is found off-site within three metres of the property boundary, it falls under Management Category D: Report. Lenders typically do not require mortgage retentions for such cases, recognising that property owners have no control over neighbouring land. Instances where infestations are beyond the three-metre boundary are not formally categorised or reported to lenders but should be documented in site notes.

The 7-metre rule for Japanese Knotweed, previously used for risk assessment, has been replaced by more nuanced considerations in the updated RICS guidance.

It primarily focused on the distance of knotweed from buildings and boundaries, with 7 metres being the defining measurement. However, the new guidance emphasises visible above-ground elements, material damage to structures, impact on amenity space and off-site encroachment within 3 metres.