Standard home insurance rarely covers Japanese knotweed, because most buildings policies exclude damage caused by tree roots, plants and gradual processes. That surprises many owners, who assume the plant would be treated like storm or flood damage. Our knotweed FAQs put this alongside the other questions owners ask, and this page explains why cover is usually excluded and what a separate indemnity policy can and cannot do in a sale.
Does home insurance cover Japanese knotweed?
Home insurance does not usually cover Japanese knotweed, because standard buildings policies exclude damage caused gradually by plants, roots and vegetation, treating knotweed as a maintenance and remediation matter rather than an insured peril like fire or storm. A few specialist or enhanced policies offer limited knotweed cover, but it is the exception. So the cost of treating a stand normally falls to the owner, which is why a professional programme with an insurance-backed guarantee matters: the guarantee, not the buildings policy, is what covers future treatment.
Why do most policies exclude it?
Most policies exclude knotweed because insurers treat it as a gradual, foreseeable problem rather than a sudden accidental event, and because the plant is widespread and expensive to remediate, which makes it uncommercial to cover as standard. Damage from roots and vegetation is a common general exclusion for the same reason. This is why owners cannot simply claim on their buildings insurance to have a stand treated, and why the practical protection comes from a treatment programme and its guarantee rather than from the policy.
What is knotweed indemnity insurance?
Knotweed indemnity insurance is a separate one-off policy sometimes used in a sale to cover a defined financial loss if knotweed later proves to affect the property, but it does not pay for treatment and does not make the plant go away. It is a legal-risk product, not a remediation one. Because it addresses a narrow financial exposure rather than the stand itself, a lender will often still want a proper treatment plan and guarantee, as our guide on indemnity insurance explains in full.
What actually protects a homeowner?
What actually protects a homeowner is a professional treatment plan backed by an insurance-backed guarantee, because that combination deals with the plant and funds any regrowth, and it is what a lender accepts. Audited Property Care Association members issue guarantees, typically for 10 years, backed by an insurer so the cover stands even if the contractor stops trading. This is the real protection, distinct from a buildings policy that excludes knotweed and an indemnity policy that only covers a defined financial loss. Our mortgages page shows how it fits a sale.
Common questions
- Can I claim on my insurance to remove knotweed?
- Almost never, because standard buildings policies exclude damage from plants and roots. The cost of treatment normally falls to the owner, with an insurance-backed guarantee covering any regrowth after a professional programme.
- Is indemnity insurance the same as treatment?
- No. Indemnity insurance covers a defined financial loss in a sale but does not treat the plant or remove it. A lender will often still want a treatment plan and guarantee alongside or instead of it.
- Does having knotweed raise my premium?
- It may affect what cover an insurer offers or exclude knotweed specifically, and it is worth disclosing where a policy requires it. The bigger financial factor is the cost of treatment, which the guarantee then protects.