An Uninvited Guest - Japanese Knotweed

An estimated 5% of all UK properties are affected by invasive species such as Japanese knotweed.

Japanese knotweed is a fast-growing extremely robust perennial that forms clumps, similar to bamboo, growing up to 2m high. The plant can block drains, undermine foundations and even invade your home, which can reduce the value of your property by up to 20% and prevent mortgage applications being approved.

Buying and selling property

People selling a property are required to complete a Property Information Form, also known as a TA6. Selling point 8 asks you to state whether Japanese knotweed is present on your property, this includes gardens and any additional land being sold in conjunction with your property.

Your conveyancer will send this form to your buyers as part of the contract pack. The contract pack is then reviewed by your buyers’ conveyancer before proceeding.

If you are selling, it is your responsibility to check the garden for Japanese knotweed, report its location and provide a management plan for its eradication from a professional company. If this is not carried out, you could be liable for any or all out of pocket expenses caused by this issue, including a depreciation in property value.

If you are buying a property, please check the contract pack. Your conveyancer will review your Property Information Form. The presence of Japanese knotweed can result in your mortgage lender requiring assurances that it will be eradicated before agreeing a mortgage offer. This plan should be provided by the seller before the purchase is completed. Always seek legal advice from a property solicitor or conveyancer before proceeding with your purchase.

Extension and planning issues

Japanese knotweed can grow up to 10cm a day during the summer, but dies back in the winter. As stated above, the perennial can cause damage to foundations and drains, therefore before planning an extension it’s important to check your land does not contain any Japanese knotweed, likewise a site appraisal would be required before building development work. Our planning team is supported by property and planning solicitors, which is unique; consequently we can offer you advice, a site appraisal and legal support depending on your requirements.

For more information on this subject, or any other property or planning issue, please call Anna Russell-Knee on 0207 449 3134 or email anna.russell-knee@attwells.com.