The insurance-backed knotweed guarantee

At SE Knotweed, an insurance-backed guarantee is the document that commits an audited contractor to return and re-treat at no further cost if knotweed regrows within the term, with an insurer standing behind it if the contractor cannot. It is what a mortgage lender accepts.

What is an insurance-backed guarantee?

An insurance-backed guarantee, often called an IBG, is a written warranty on knotweed treatment that commits the contractor to return and re-treat free of charge if the plant regrows within the guarantee term. The insurance element means a separate insurer honours that promise if the contractor ceases trading.

At SE Knotweed, it is the document we build every treatment plan towards, because it is what turns a completed job into something a lender and a buyer can rely on years later.

Why do mortgage lenders accept it?

Mortgage lenders accept an insurance-backed guarantee because it moves the future risk of regrowth off the property and onto the contractor and their insurer. A valuer can then treat the knotweed as a managed issue rather than an open-ended liability.

This is the mechanism that unblocks a stalled sale, and our mortgages page explains how the survey, plan and guarantee fit together for a lender.

What does the guarantee cover?

The guarantee covers further treatment of the same stand if viable knotweed reappears within the term, including the labour, herbicide or excavation needed to deal with it, at no additional cost to the owner.

It sits alongside the management plan and the monitoring visits, so regrowth is caught and treated under the cover rather than becoming a new bill. What it does not cover is new knotweed arriving from elsewhere, such as a neighbour's untreated stand.

How long does the guarantee last?

At SE Knotweed we back completed work with a 10 year company guarantee, and insurance-backed guarantee (IBG) cover is available up to 15 years, which sits beyond the 10 year term most mortgage lenders look for. The right term for your site is set out with the management plan.

As a PCA-approved and TrustMark-registered firm, our guarantee is written so it can be assigned to a buyer for the remaining term, which is what lets a sale proceed years after the treatment.

Who stands behind the guarantee?

Two parties stand behind an IBG: the contractor who did the work and commits to re-treat, and an insurer who honours the guarantee if that contractor is no longer trading when a claim is made. That second layer is the reason it carries more weight than a contractor's word alone.

Because the guarantee is only as good as the firm and the accreditation behind it, we set out both with your survey and plan.

Common questions

What is the difference between a guarantee and an insurance-backed guarantee?
A plain guarantee relies on the contractor still trading. An insurance-backed guarantee adds an insurer that honours the cover if the contractor ceases trading, which is why lenders prefer it.
Is the guarantee transferable to a buyer?
Accredited guarantees are usually transferable to a new owner for the remaining term, which is what lets a sale proceed. The exact terms are set out with the plan.

Book a survey and get a costed plan

Tell us the address and what a surveyor flagged. We confirm the plant, record the RICS category and set out the figures.

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Call 01924 944600