Japanese Knotweed UK – Is it a real problem for the homebuyer?

It’s likely you’ve heard of Japanese Knotweed, although you may not be aware of the huge problems it can cause. Far from a mere dandelion or nettle, Japanese Knotweed can lead to structural problems, prosecutions and inability to secure a mortgage.

So, what is Japanese Knotweed and how big a problem is it when you’re trying to buy a house? We’ve put together some information to answer all your questions and point you in the direction of all the help you need.

What is Japanese Knotweed?

Japanese Knotweed (Fallopia Japonica) is an extremely fast-growing weed with a bamboo-like appearance. Its creeping stems penetrate deep underground and it can reach heights of over 2 metres.

It’s not native to this country and was originally introduced as an ornamental plant. Now classified as invasive, it can be very difficult to control and destroy, which is a problem if you find it on your property/somewhere you want to buy.

Japanese Knotweed identification

Japanese Knotweed is found all over the UK as a perennial weed; it dies back in winter but shoots up in early summer from deep underground stems.

In spring, you might notice the red/purple shoots emerging from pink/red buds at ground level. These shoots grow quickly into dense, bamboo-like canes of up to 2.1m (7ft) tall. If you look closely at the canes, you’ll spot tell-tale purple flecks.

If you’re attempting Japanese Knotweed identification, the leaves are ‘shovel’ or slightly heart-shaped and can measure up to 14 cm long. They grow in a zigzag pattern along the plant’s stems but will die off in winter.

Japanese Knotweed flowers grow in ‘tassels’ up to 15 cm long and are creamy-white. They appear in late summer/early autumn and are deceptively attractive, considering the nuisance this plant has become!

It’s very easy to misidentify the plant as it is easily confused with other, similar-looking plants. This makes Japanese knotweed identification tricky for the untrained eye.

Japanese Knotweed UK law

It’s not illegal to have Japanese Knotweed on your property. However, under Japanese Knotweed UK law, you might face prosecution or a community protection notice if it spreads to someone else’s property.

If you discover a neighbour has it, you should let them know. If they don’t do anything about it and it spreads to your property, you may be able to file a claim against them.

It’s legal for you to tackle the weed yourself, although it’s a notoriously tricky task. Plus, Japanese Knotweed is classed as ‘controlled waste’ under the Environmental Protection Act 1990. That means you cannot dispose of it with normal waste, compost it or put it in green waste collection. You’ll need to seek out licensed sites who specialise in the disposal of Japanese Knotweed.

The seriousness of Japanese Knotweed UK law and complications of disposal mean you may like to use the services of a specialist, who will be skilled in the proper removal and destruction of the whole plant.

Why is it a problem for the homebuyer?

One of the reasons Japanese Knotweed is such a huge problem is that is can cause massive damage to buildings, sewers and paving. It grows extremely quickly, penetrating cracks and joints as it spreads. If found at the property you want to buy, you are likely to have issues getting a mortgage.

As the buyer, you can take comfort knowing that it is the seller’s responsibility to check for Japanese Knotweed and they must tell you if it’s present. It is a criminal offence to sell a property without disclosing the presence of Japanese knotweed. However, for total peace of mind, it’s worth getting your own checks done and our Chartered Surveyors can help.

If you don’t find out about it in good time, it might create problems later in the buying process or even lead to a misrepresentation claim after the sale. It’s best to avoid this hassle and upset by getting your own survey completed to check and double check, not least because it can be tricky to identify the weed, especially in winter.

What should I do if my survey uncovers Japanese Knotweed?

Don’t panic! Just because Japanese Knotweed is found or suspected at a property it doesn’t mean disaster. Be thankful that you discovered it before the sale went through.

As Japanese Knotweed identification is often difficult and it can be confused with other plants, the first thing to do is double check it actually is the dreaded weed before taking action or negotiating the house price.

Next, it’s likely that your mortgage lender will want guarantees for Japanese Knotweed removal. The seller should provide a guaranteed management plan by a professional eradication company and this is usually sufficient for the mortgage company. You can then proceed with your purchase.

Get in touch

Japanese Knotweed identification is another thing to tick off your list when buying a house. If you need help with this essential task, get in touch. We take this issue very seriously and our surveyors attend regular training enabling them to identify the plant during pre-purchase surveys. We also work closely with local specialists regarding any suspected issues we discover.

Please get in touch to discuss how we can help.