Updated: April 12, 2023
Japanese Knotweed Mortgages
Trying to get a mortgage on a property with Japanese Knotweed? It can be done! Find out exactly what you need to do in our in-depth guide.
Ask A Quick Question
We know everyone's circumstances are different, that's why we work with mortgage brokers who are experts in all different Property Types. Ask us a question and we'll get the best expert to help.

No impact on your credit score

Author: Pete Mugleston - Mortgage Expert, MD
Updated: April 19, 2022
Japanese Knotweed is an aggressive, fast-growing weed that was introduced to the UK in the 1800s and is now believed to be present at or near as many as 5% of UK buildings.
With roots that spread as far as 7 metres, it can be destructive to buildings, and may affect your ability to secure a mortgage, but with the right advice, it’s doable.
In our guide to Japanese Knotweed and mortgages, you’ll learn how to get a mortgage on a property when the weed is present, what risks it poses and where to get the right advice.
Can you get a mortgage on a property with Japanese knotweed?
Yes, although not all mortgage providers will lend where it’s present within the property boundaries.
How close the weed and its roots are to the boundaries of the property will be the major concern of most lenders who are willing to consider this type of mortgage.
Although Japanese knotweed has been considered a major threat to surrounding structures for some time, recent research by the parliamentary Science and Technology committee suggests that they are no more of a threat than other similarly invasive vegetation.
As such, there are an increasing number of lenders willing to consider Japanese knotweed applications on a case-by-case basis.
Get Started with a Broker
Maximise your chance of approval with specialist advice from a mortgage expert.
Defining the risks
Japanese knotweed exploits any gaps in property foundations, masonry and brickwork, and has the potential to cause subsidence, and/or damage to walls and sewerage pipes.
It is incredibly resilient, and often lies dormant underground when believed eliminated. It therefore also has the potential to impact future plans to expand your property, as interference can revive the knotweed.
To help mortgage lenders decide how risky the presence of Japanese knotweed is, they use the following RICS (Royal Institution of Chartered Surveyors) risk matrix:
- Risk Category 1 – Japanese knotweed is located more than 7 metres from the boundary of the property, but not within its boundaries. This could be on a neighbouring property or on public land, particularly if located nearby railway embankments, where the weed is commonly found.
- Risk Category 2 – Located less than 7 metres from the boundary of your property, but not within the boundaries.
- Risk Category 3 – Located within your property boundaries, but is more than 7 metres from the actual property (referred to as habitable space).
- Risk Category 4 – Located within 7 metres of your habitable space, or is already causing damage to the structure(s).
Mortgage lenders assess every application based on the risk to their investment, so anything that could affect the value of the property will reduce their appetite to lend.
Therefore it’s likely to be more difficult to secure a mortgage in these circumstances, especially for those properties in category 3 and 4.
Will a mortgage survey pick it up?
Not always. Although surveyors typically check for Japanese knotweed, on properties with large plots of land, or where the weed is dormant, it will not necessarily be found unless a specialist survey is requested.
That said, if the current owner is aware of the weed’s presence, they have an obligation to provide a report on the severity of the issue, and what management practices are already in place.
How to get a mortgage on a property with Japanese Knotweed
Here are the steps to take…
- Order a survey: If you’re concerned about the presence of Japanese knotweed, organise a specialist survey on the property by a RICS surveyor who is approved by the PCA (Property Care Association) and obtain a full report of the current situation.
- Seek advice from a broker: This should be one with specific experience in securing mortgages on properties with Japanese knotweed. The brokers we work with are experts in this niche of lending, and may even be able to help to secure a lender for properties defined as risk category 4.
They also work closely with knowledgeable PCA surveyors and reputable invasive weed management companies, so you can feel confident that you’ll be able to meet any potential lending conditions adequately. Our five star introduction service will match you with a broker who has the experience most relevant to your needs, in no time. Simply complete this form or contact us on 0808 189 0463 and provide us with as much information as you can about your circumstances and needs. - Consider whether removal/management is necessary: Based on the advice and guidance of the specialist broker, you can make a decision about whether the management or removal of knotweed is necessary. If complete removal is over budget, they should be able to recommend a lender with more lenient criteria, who would accept a management plan, depending on the results of your report.
Our Broker-Matching Service Guaranteed!
We want you to have complete confidence in our service, and get the best chance of securing your mortgage. We guarantee to get your mortgage approved where others can’t – or we’ll give you £100*

Lender availability and criteria
There are currently more than 35 lenders who will consider residential mortgage applications for properties with Japanese knotweed present.
This includes some major high street lenders, such as HSBC and Santander, however, each has their own specific criteria with regards to the level of risk acceptable and almost all mortgages are offered conditionally.
Of course, standard eligibility criteria, such as affordability and creditworthiness apply. The more specific eligibility requirements, however, depend on the severity of the knotweed issue and the individual lender’s perception of that risk.
Some lenders will only consider properties where the knotweed risk is assessed to be 1 or 2 on the RICS knotweed risk matrix. If the risk is assessed to be category 3 or 4, lenders typically impose stricter conditions, such as:
Japanese knotweed removal
If removal of the knotweed is a condition of your mortgage, the lender will expect it to be carried out by a professional Japanese knotweed management contractor who is a member of the PCA or INNSA (the Invasive Non-Native Specialists Association).
This work may also need to be guaranteed for up to 10 years.
Many types of knotweed appear similar, and can easily be mistaken by the untrained eye. When you consider this alongside the evasiveness of Japanese knotweed, and its potential to spread when it’s dug up, it’s not advisable to try to remove it yourself.
It’s also a controlled waste, so private individuals cannot adequately dispose of the uprooted plants.
Further information can be found in the Invasive Weed Control Document Library, which was compiled by the Property Care Association, and can be downloaded here for free.
A verified treatment plan
Total eradication of the weed can be expensive, however, some lenders will consider a more affordable management plan to be acceptable, so long as you can prove that this is in place with a PCA or INNSA approved firm, and in some cases, is fully paid for in advance.
Any treatment plans will need to be covered by a 5-10 year insurance-backed guarantee, and a full and detailed report of the treatment plan is usually also required. The mortgage will typically be placed on hold until the first treatment has commenced.
Indemnity insurance
An indemnity policy to cover potential future treatment of Japanese knotweed may be recommended by a surveyor in some cases, as this type of treatment would not generally be covered by standard buildings insurance.
Whilst this is not usually a condition of lending, it may help to improve the lender’s confidence in your application. Brokers who specialise in Japanese knotweed mortgages will be able to make recommendations about suitable insurance policies, and providers.
Reviews
Fast and easy
Fast and easy! The advisor has been more than helpful and dealt with my enquiry quickly !
Sam J

Great communication
Great communication along the way with clear advice and support from a qualified broker! I would highly recommend this service.
Denise R

Great- would recommend 👍🏻
Great, 5 star efficient service. Would recommend
Allen

Get matched with a broker experienced in Japanese knotweed cases
Finding a lender when your purchase property is at risk from Japanese knotweed can be difficult, but with the right advice and guidance, it’s perfectly possible in the vast majority of cases.
We work with a wealth of brokers with expert knowledge in securing mortgages for properties with this issue present, and can easily put you in touch with those who have experience that most closely matches your specific level of knotweed risk.
Contact us today on 0808 189 0463 or complete this form and we’ll begin the introduction process immediately.
This service is entirely free of charge, and the brokers we work with operate on a success-only fee structure, so you’ll only pay them if they help you to secure a mortgage.
Get Started with a Broker
Maximise your chance of approval with specialist advice from a mortgage expert.
FAQs
Whilst it’s not illegal to have Japanese knotweed on your property, it’s illegal to cause the spread of it, so you’re obliged to keep it under control.
If you sell your home, always disclose the presence of knotweed to the buyer, as failure to do so could lead to prosecution.
There are commercial mortgage lenders who would consider this, although to a lesser extent than residential lenders.
Like residential mortgages, the inherent risk would be used to assess the loan, however, the intended purpose of the property will also be taken into consideration.
We can put you in touch with brokers with experience in sourcing commercial lenders in this niche.
It can, but this depends on the severity of the issue, as determined by the RICS risk matrix. If you’re planning to sell a property with Japanese knotweed present, it may be worth investing in professional treatment to remove or control it, before you go to market, to minimise any impact on its market value.
Ask A Quick Question
We know everyone's circumstances are different, that's why we work with mortgage brokers who are experts in all different Property Types. Ask us a question and we'll get the best expert to help.


Pete Mugleston
Mortgage Expert, MD
About the author
Pete, an expert in all things mortgages, cut his teeth right in the middle of the credit crunch. With plenty of people needing help and few mortgage providers lending, Pete found great success in going the extra mile to find mortgages for people whom many others considered lost causes. The experience he gained, coupled with his love of helping people reach their goals, led him to establish Online Mortgage Advisor, with one clear vision – to help as many customers as possible get the right advice, regardless of need or background.
Pete’s presence in the industry as the ‘go-to’ for specialist finance continues to grow, and he is regularly cited in and writes for both local and national press, as well as trade publications, with a regular column in Mortgage Introducer and being the exclusive mortgage expert for LOVEMoney. Pete also writes for OMA of course!
Continue Reading
Getting a Mortgage on an Apartment
Mortgages for Properties With Asbestos
Buying A House With Subsidence
Getting a Mortgage on a Steel Frame Property
Non-Standard Construction Mortgages
Getting a Mortgage on an Uninhabitable Property
Getting a Mortgage When Buying Property From Family
Getting a Mortgage on a Concrete House
A Guide to Buy-to-Renovate Mortgages
Getting a Mortgage on a Flat Above a Shop
Getting a Mortgage On a Flat Roof Property
Single Skin Wall Property Mortgages
Getting a Mortgage on a Property Under 30 Square Metres