Japanese Knotweed – Yes, No or Knot Known – The Big Question.

Anyone buying or selling a house will come across a TA6 Property Information form. The 3rd edition of this Law Society document must be completed by anyone selling a property; at 16 pages long with 14 sections to fill in, it can be an onerous task.  The seller is obliged to answer a long list of questions about the property ranging from parking arrangements to rights of light.

Section 7.8 of the form asks “Is the property affected by Japanese knotweed? There are 3 answers to choose from which are Yes, No, Not Known.

If the answer is ‘Yes’ then the owner must state whether there is a Knotweed Management Plan (KMP) in place and if so supply a copy to their solicitor.

When the seller answers ‘No or Not Known’ it is very important that they are certain of this. Not everyone knows about Japanese knotweed, the non-native invasive weed that has the potential to significantly jeopardise the saleability of a property. As the two pictures below demonstrate, Japanese knotweed can cause serious structural damage to property.

But what exactly is meant by the words “affected by Japanese knotweed” and how can a property owner identify it.

Firstly, a property is considered as being affected by knotweed if it is found on the property or within 7 metres of the property boundary. To help understand and categorise the level of risk that the knotweed presents to the property, the Royal Institution of Chartered Surveyors (RICS) have created a “risk” table. The area around the knotweed is referred to as the “risk zone” and its location in relation to the buildings should be formerly recorded and the risk category accurately assessed.

Japanese Knotweed is an invasive and resilient weed that can re-grow from the deep rooted rhizomes and re-emerge many years after treatment. In some cases it is possible that the very deep rooted Japanese knotweed rhizomes remain in a viable state, and may do so for up to twenty years or so. These rhizomes will eventually re-grow, especially if they get disturbed. If knotweed is left to grow untreated for a number of years it has the potential to cause damage to hard landscaping and buildings on property and could also encroach into neighbouring properties.

To help with identification of Japanese knotweed the following images show how it appears throughout the seasons. Alternatively, Japanese Knotweed Ltd provides a free email identification service to help identify photographs. Property buyers, sellers, Estate Agents, Conveyancing Solicitors can simply send a few images by email to ident@knotweed.co.uk for advice.

If knotweed is identified then the best course of action for the owner of the property will be to instruct a specialist knotweed professional, registered with the Property Care Association (PCA), to carry out a survey.

A knotweed survey will provide a detailed report and drawing showing the anticipated extent of the knotweed contaminated ground and its location in relation to the buildings and the property boundary. The report will include the Royal Institute of Chartered Surveyors (RICS) property risk category and it will record any visible signs of damage caused by the knotweed to the buildings, ancillary structures or hard standing/paving and where possible and applicable it will identify knotweed in the neighbouring gardens. Where applicable, the survey will provide information and advice to help with cases of encroachment, misrepresentation regarding the Law Society Property Information TA6 Form (3rd edition) or professional negligence.

 

The remedial work should be carefully chosen in accordance to the owner’s plans, the location of the knotweed and the severity of the problem. The most professional and recognised approach is to implement a Knotweed Management Plan (KMP). A KMP is a document prepared by Japanese Knotweed Ltd, in good-faith and in accordance with the professional standards and guidelines from the Property Care Association (PCA).  This KMP will ensure that the knotweed problem is professionally managed and this document will meet the requirements of the majority of UK mortgage lenders.

For further information or advice visit www.japaneseknotweed.co.uk or email survey@knotweed.co.uk

Title image credit JapaneseKnotweed.co.uk – Used with full permission.

 

 

 

Alex Evans

You May Also Enjoy

Estate Agent Talk

Renting an Apartment for Streaming and Gaming: What to Check Before Paying the Security Deposit

For those who stream or compete online from home, choosing a place to live becomes a task with many variables. Beautiful photos in a listing say little about whether an apartment is suitable for a home studio, stable livestreaming, and long hours in front of a monitor. The decision should be based not on the…
Read More →
Breaking News

London rents outperform property values

The latest research by London lettings and estate agent, Benham and Reeves, has revealed that rental growth has outperformed house price growth across 26 of London’s 32 boroughs since the start of the year, with rents continuing to climb despite weaker property price performance across much of the capital. Benham and Reeves analysed the average…
Read More →
Breaking News

Rental property availability falls

The number of rental properties available across England fell by 12.1% during the third quarter of 2026, according to new analysis by Dwelly, highlighting an increasingly competitive rental market in many parts of the country. Dwelly is one of the UK’s largest rental property management groups, with more than 15,000 properties under management. The firm’s…
Read More →
Breaking News

Average advertised rents surpass £1,400 for the first time

The average advertised rent of homes outside London has risen to a new record of £1,418 per calendar month, up 1.5% this quarter: Despite a new record rent, annual rental growth has returned to a more stable level of +2.4% Number of available rental homes nationally is 2% lower than a year ago, while renter…
Read More →
Breaking News

Barclays unlocks wider mortgage access for company directors

Limited company directors who meet the income threshold can now have their Profit After Tax (PAT) considered in their affordability assessment regardless of property value The change means that, for a wider group of limited company directors, Barclays will consider a fuller view of the applicant’s income The update is the latest in a series…
Read More →
Breaking News

Homebuyer demand fall in Q3

The latest sales demand data from eXp UK has revealed that homebuyer demand in England slipped by -1.6% in Q3 2026. The analysis shows that just five counties managed positive growth during the quarter, suggesting that buyers may be holding back, adopting a wait-and-see approach ahead of what promises to be a vital Autumn Budget –…
Read More →