Should You Buy a House Infested with Japanese Knotweed?

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Knotweed Services is a company that provides education, awareness, and professional services relating to Japanese knotweed. Japanese knotweed causes damage to houses as it grows through cavities and cracks in asphalt concrete and walls. It has been estimated that Japanese Knotweed can devalue homes by up-to 15%

With that in mind, homeowners may be offered a property that’s already infested with Japanese knotweed or one that was previously infested but no longer is. In either case, whether buyers know about a property’s chequered past up front or not, it’s important for them to understand how Japanese Knotweed affects home ownership and a property’s value if they want to buy one.

What is Japanese Knotweed?

Japanese knotweed is a fast-growing, invasive plant species that can grow up to 3 meters tall. It has long, narrow leaves and produces white flowers in early spring. The seeds of this weed are dispersed by humans, wind or water and the plants spread incredibly quickly.

Can Japanese knotweed damage a house?

Japanese knotweed causes structural damage to homes. It grows by means of rhizomes which spread out horizontally from the base of the stem. These roots damage building structures such as houses, roads, pipes and sewers. It spreads easily from house to house, so eradicating it isn’t easy. And if there are any weak spots in the building, they could be exploited by the pest.

If you buy a house where there’s Japanese knotweed growing, then you take on the responsibility of controlling its growth and making sure it doesn’t spread into neighboring properties. In addition, you’ll need to be sure that the plants don’t become too large so they threaten your physical property and enjoyment. As for the severity of the infestation, it will determine how long, hard and expensive it may be to eradicate them. Therefore, it is important to know how to effectively remove Japanese knotweed so that they don’t return again.

Are buyers notified about the presence of Japanese Knotweed?

Sometimes, potential buyers are notified by the seller or the estate agent that Japanese knotweed has been found on a property. Some properties may explicitly state that they are affected by Japanese knotweed, while others may try to hide or downplay this fact.

When you buy a property, your solicitor should ask the seller to complete a TA6 Property Information Form. The history of the property is explored, and the seller provides a complete account of any outstanding issues. Legally the seller is required to fill in the TA6 form, if they tick “unknown” and then you later find Knotweed on the property, you may be able to hold them liable. This is why a low cost survey is always worth having.

Assessment From a Knotweed Surveyor

A RICS assessment framework has four key categories of the threats posed by Japanese knotweed. This guidance from RICS is the primary source of information mortgage lenders, building societies and banks use when accounting for knotweed in a property, as well as what solutions the seller is offering. If your property is classified as anything other than level 3 on the assessment framework, PCA-approved knotweed removal companies are a necessity. We can help – find out more about our Knotweed Surveys.

So..... Should I Buy a Home with Japanese Knotweed?

You should do your best to make sure your home is free of knotweed before you buy it. As a buyer, you might want to negotiate a contract that states the seller will remove the knotweed, or, if you are the seller, get a management plan in place to ensure you’re doing everything you can. However, if you are aware of the extent of the problem and get a mortgage approved, it is your choice how much you are willing to do to remedy the situation.

If you are going to continue with the purchase, first establish just how big your Japanese knotweed problem might be...

If you’re worried about Japanese knotweed, it’s worth getting one of our professional Japanese Knotweed surveys carried out. Knotweed Services can identify the problem, as determined by RICS guidelines, and can put together a treatment and management plan. Click here for more information.

Cooperate with Neighbours and know your responsibility

If you’re buying a property with Japanese knotweed, it’s important to know that you must continue to monitor and control the plant, or it will spread. If knotweed spreads to adjacent land, it could create a problem for both of you. Similarly, if it originated in your neighbour’s garden, it’s worthwhile finding a solution that works for both of you.

Communicate with Your Mortgage Lender \ Bank

Pretending you don’t know you have Japanese knotweed is an unwise strategy. As a buyer, you must take precautions against future damage from knotweed even though the weed hasn’t yet invaded your property. By working with a professional Japanese knotweed removal company and understanding your mortgage lender’s requirements, you can create a plan for getting rid of the weed.

The Good News - Kind of...

We have worked with thousands of home owners over the last decade that have purchased properties with Knotweed present and we have successfully treated every. Single. One.

So, if you’ve found your dream home and really don’t want to let Japanese Knotweed get in the way of you getting your dream home either negotiate with the seller to employ Knotweed Services or negotiate a discount to cover any future fees.

Knotweed Services are able to help homeowners satisfy a mortgage lender’s requirement that they hire a professional expert to remove knotweed. This is what you’ll get from us:

  • Full members of the Property Care Association (PCA) 
  • Provide the best residential removal prices. Find out more about our costs.
  • We work with both the residential and the commercial sectors. Check out our portfolio to see some of our latest works.
  • We are available nationwide, with surveyors and depots dotted all over the UK, meaning you’ll get a local technician
  • We have bespoke systems available to report real time data on treatment records, visits etc
  • We use state of the art technology and are ahead of the curve when it comes to the latest treatments. We are the first Japanese Knotweed Company to offer electrical removal
  • Up-to 10 year insurance backed guarantees – giving you tremendous peace of mind

Have Japanese Knotweed on your land? Click here: to find out where you stand.


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