Selling a house with Japanese knotweed

Japanese Knotweed | 24th March 2021

Japanese knotweed (Reynoutria japonica, Fallopia japonica, and Polygonum cuspidatum) is arguably the most widespread and pernicious weeds in the UK. Since it was introduced in the country as an ornamental plant by the Victorians, the weed is now regarded “the most problematic species”—and for good reason.

The herbaceous perennial plant is so tenacious that it grows through underground pipes, tarmac, brick walls, and even solid masonry foundations—leading to property devaluation. In one case reported by the BBC, the invasive species knocked down the value of a Hertfordshire house from £305,000 to £50,000.

Selling a house with Japanese knotweed is typically an uphill task, marred by legal and insurance costs. But it is not impossible! As long as you remain proactive with eradicating the weed by disclosing its existence as per the law and establishing an insurance-backed management plan with the help of a PCA-accredited contractor, selling an ‘infested’ house is possible.

Read on for more on how to identify Japanese knotweed, removal, and how to sell a house with Japanese knotweed.

Japanese Knotweed Identification

Japanese knotweed identification is the first step to getting rid of the plant and preserving the value of your property. According to the Royal Institute of Chartered Surveyors (RICS), the weed is often found on land near a public watercourse, railways, cleared sites, and homes next to unattended land. It may lie dormant for a prolonged period—only to spread ferociously when the ground is disturbed.

The tell-a-tale sign of Japanese knotweed include:

  • Distinctively red-tinged shoots
  • Large shovel-shaped leaves with a tapered point and flat base.
  • A zig-zag leaf arrangement along the stem.
  • A hollow stem.
  • Cream/white flowers before Autumn.
  • Purple nodes.

After a suspected Japanese knotweed identification, it’s advisable to contact an PCA Company so that a Japanese knotweed surveyor can make a closer inspection. Some companies such as PBA Solutions offer a FREE homeowner inspections where Japanese knotweed has been identified, a service that can otherwise cost £250-£450+VAT.

Japanese Knotweed Removal

Selling a house with Japanese knotweed demands extra measures to ensure potential buyers are making an informed decision. You can either pay up-front by establishing an insurance-backed management plan or completely remove the weed from the property. This helps the buyer avoid Japanese knotweed mortgage problems—while helping you make a sale.

And according to the law, sellers are required to disclose any current or previous invasions by the Japanese knotweed in the Law Society’s TA6 form. The form reads, “Is the property affected by Japanese Knotweed? (Yes, No or Don’t know). If Yes, please state whether there is a Japanese Knotweed management plan in place and supply a copy.”

While there are suggestions of DIY Japanese knotweed removal techniques floating around on the internet, they are not advisable. Effective eradication is a complicated and the process demands the services of qualified and experienced professionals.

Japanese Knotweed Removal Cost

Having a treatment plan is important and Japanese knotweed removal costs will vary depending on the contractor, characteristics of the land affected, and the severity of infestation. But regardless of the Japanese knotweed removal cost incurred, the treatment plan must come with an indemnity policy and 10-year Japanese knotweed insurance guarantee.

Alternatively, you can sell a house with Japanese knotweed via auctioning it to a willing buyer or cash sales to bypass the hurdle of Japanese knotweed mortgages on the buyer’s end. They will result in a lower price being achived for the property. A nominal figure for loss of value due to the presence of Japanese knotweed is in the region of 10% of the property value.

Speak to our experts

For more on Japanese knotweed removal and preserving the value of your property, call PBA on 0203 174 2187 or 01202 816134.

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