At SE Knotweed, a knotweed compensation claim is a private nuisance action for the cost of dealing with encroachment from a neighbour who knew of the plant and failed to act, and it needs survey evidence.
At SE Knotweed, a Japanese knotweed compensation claim is a private nuisance action brought where knotweed has encroached onto your land from a neighbour who knew of the plant and failed to take reasonable steps to control it. It seeks the cost of treating and monitoring the encroachment and, in some cases, damages for the interference with the use of your property.
It is not a claim you can bring simply because a neighbour has knotweed; the plant must have spread onto your land and the neighbour must have been in breach of a duty. We provide the survey and, where needed, the expert evidence, while a solicitor runs the legal case. Take legal advice before starting.
A knotweed claim must prove that the plant is Japanese knotweed, that it encroached onto your land from the defendant's, that the defendant knew or ought to have known it was present, and that they failed to take reasonable steps to prevent the spread. Each element needs evidence, and the technical parts come from a survey.
Published guidance on knotweed is treated by the courts as fixing the point a landowner ought to know, so the date they were told, or should have realised, matters. Our neighbour responsibility page explains the knowledge and breach tests that decide these cases.
You can usually recover the cost of treatment and monitoring and, where shown, damages for loss of the amenity of your land, but a residual fall in market value is often not recoverable. In Davies v Bridgend County Borough Council [2024] UKSC 15 the Supreme Court held that residual diminution is not recoverable in nuisance where the encroachment happened before the defendant was in breach of any duty.
That is an important limit, and it is why we state the position accurately rather than promising a payout for lost value. What is recoverable turns on the facts and the timing of the breach, so the law pillar and your solicitor's advice matter more than any headline figure.
A claim needs evidence that confirms the species, records the source and direction of spread, maps the extent across the boundary, and quantifies the remediation and monitoring cost. A survey provides the technical findings, and where the case proceeds a CPR Part 35 expert witness report presents them to the court in the required form.
Your own dated photographs and any written report you made to the neighbour also help, because they evidence when the neighbour knew. We produce the survey and expert report; the solicitor gathers the correspondence and builds the legal case around them.
A knotweed claim can take from several months to over a year depending on whether it settles or goes to trial, because pre-action correspondence, expert reports and any negotiation each take time. Many claims settle once the evidence is exchanged, without a hearing.
Meanwhile you should still treat the stand on your own land, because leaving it lets the rhizome establish and you must declare it when you sell. Treating your side does not weaken the claim, since the survey records that the source is next door, and it protects your own sale or mortgage.
You should treat your knotweed while a claim runs, because the law does not require you to leave the plant untreated to preserve a claim, and an established stand only gets more expensive to deal with. A survey taken before treatment records the extent and source, which is the evidence the claim relies on.
We can survey the stand, produce the evidence for your solicitor, and treat it under a management plan with a guarantee, so your own position is protected regardless of how the claim ends. Contact us with your address and we will set out both the remediation and the evidence a claim needs.
Tell us the address and what a surveyor flagged. We confirm the plant, record the RICS category and set out the figures.