Can I buy a property that has Japanese knotweed?
By Jennifer Holmes

Can I buy a property that has Japanese knotweed?

Buying a property with Japanese knotweed: What You Need to Know

If you are considering buying a property that has Japanese knotweed growing on the property, it’s essential to understand the potential challenges and take the necessary steps to ensure that you are making a wise investment. In this blog, we will cover everything you need to know about buying a house with Japanese knotweed and how to ensure that you make a safe and informed purchase.

Understanding Japanese knotweed

Japanese knotweed is a fast-growing, bamboo-like plant that is native to Japan. It was introduced to the UK in the 19th century as an ornamental plant but has since spread throughout the country and has the potential to cause damage to buildings, infrastructure, and the natural environment.

It particularly difficult to control because it spreads quickly, exploiting any weaknesses in structures it can grow through cracks in concrete and asphalt. It also has an extensive rhizome (root) system that can reach up to 3 meters deep.

Should you buy a house with Japanese knotweed?

If you are considering buying a house that has Japanese knotweed growing on the property, there are several potential impacts that you should be aware of.

Firstly, has it been confirmed and declared as Japanese knotweed? Only experts in the field can accurately identify it, and there ae many lookalikes that can easily fool the untrained eye.

Secondly, many mortgage lenders and insurance companies are reluctant to provide loans or cover for properties that are affected by Japanese knotweed. This means that you may struggle to secure the necessary financing to complete the purchase. Speak to your mortgage advisor or lender directly to see how they approach this issue, as not all lenders have the same rules on this.

Thirdly, should you decide to go ahead with the purchase, factor in the cost of removing the plant so that you don’t carry the burden on should you consider selling up in the future. Get several quotes for a survey, as well as starting prices for treatment and removal options. You may not get a full quote at this stage until a survey has been carried out, as full costs depend on the extent and type of the infestation.

Removing Japanese knotweed

The best way to control Japanese knotweed is to have it professionally treated and removed by a specialist contractor. This process can be a long-term option if herbicide treatments are planned (typically 3-5 years) or more quickly eradicated if excavation is decided upon, but it is the only way to ensure that the plant will not return and cause further damage.

When choosing a contractor, it is essential to ensure that they have the necessary experience and qualifications to deal with Japanese knotweed effectively and in compliance with UK legislation. You should also ask for references and check the company’s reputation by checking review sites before making a decision.

You could negotiate the Purchase Price

In the UK, it’s a legal requirement to disclose any information about Japanese Knotweed when selling a property. However, it’s the responsibility of the buyer (and their solicitor) to carry out due diligence and to seek any necessary information about the presence of Japanese knotweed on a property before making a purchase. Always request this information from the seller.

See our blog “Selling a House with Japanese knotweed: What You Need to Know” for more details on what the seller should be doing to attract a sale.

Going ahead with the purchase

If you do then consider buying a house with Japanese knotweed, it is important to negotiate the purchase price with the seller. Given the potential impact that the plant can have on the value of the property, you may be able to negotiate a lower price to reflect the cost of removing the plant or (not advised) the potential devaluation of the property in the future should you choose not to have it treated or removed.

Get a Survey

So, you’ve decided you want to buy the property – but before taking it any further, it is always advisable to have a professional survey carried out. If the surveyor identifies Japanese knotweed growing on the property, or nearby, they will be able to provide advice on the potential impact it may have should you proceed with the purchase, and options to get it under control or completely eradicated.

This information can be used to negotiate the purchase price and to ensure that you are fully aware of the financial implications of buying a house with Japanese knotweed.


Buying a house with Japanese knotweed is possible but can definitely be challenging. First things first – is it Japanese knotweed? Getting it identified is easy via our online ID tool, or you can get a pre-purchase survey carried out by a Japanese knotweed specialist. With the right advice, it is possible to make a safe and informed purchase, it just may take a bit longer!

If you have any questions for us get in touch.