What is Japanese Knotweed?

Japanese Knotweed is an invasive plant species that spreads rapidly and can cause damage to structures, hard surfaces, and drainage systems. It must be handled by licensed professionals.

Can Japanese Knotweed affect my mortgage?

Yes. Many lenders will refuse mortgage applications if Japanese Knotweed is present unless a PCA‑accredited treatment plan with an insurance‑backed guarantee is in place.

Do you provide insurance‑backed guarantees?

Yes. All our treatment plans include PCA‑compliant documentation and long‑term guarantees accepted by major UK lenders.

How do I know if I have Japanese Knotweed?

Common signs include bamboo‑like stems, shield‑shaped leaves, and rapid growth in spring. If unsure, we offer professional surveys to confirm identification.

Are your surveyors qualified?

Yes. All our surveyors hold the CSJK (Certificated Surveyor in Japanese Knotweed) qualification, the industry‑recognised standard for professional Japanese Knotweed identification and assessment. This ensures every survey is carried out to PCA‑approved standards and is fully accepted by mortgage lenders, solicitors and local authorities.

What does a Knotweed survey include?

Our surveys include site inspection, mapping, risk assessment, photographs, and a full written report suitable for mortgage lenders, solicitors, and property transactions.

What treatment options do you offer?

We provide herbicide treatment, excavation, root barrier installation, and combined management plans depending on the severity and location of the infestation.

How long does treatment take?

Herbicide treatment typically takes 1–3 growing seasons. Excavation can remove Knotweed immediately but may require more extensive site work.

How much does treatment cost?

Costs vary depending on the size of the infestation, access, and treatment method. We provide free quotations and competitive pricing.

How do I book a survey?

You can call us on 0121 366 8916 or email info@i-v-m.co.uk. We offer fast appointments across the UK.

Do you offer a free initial assessment or quotation?

Yes. We provide free initial advice and quotations based on photographs, site information, or a brief discussion about the infestation. If a formal survey is required for a mortgage or legal purpose, we offer a competitively priced CSJK‑qualified survey with full documentation.

How quickly can you attend my property?

We can usually attend within 24–72 hours depending on your location. For urgent cases — such as property sales, mortgage delays, or legal disputes — we prioritise fast appointments to keep your transaction moving.

Can Japanese Knotweed come back after treatment?

If treated incorrectly, yes. However, our PCA‑approved management plans and long‑term monitoring significantly reduce the risk of regrowth. All work is backed by an insurance‑backed guarantee, giving you long‑term protection and peace of mind.

What areas of the UK do you cover?

We operate nationwide across England, Wales and Scotland. Our surveyors regularly attend properties in urban, rural and coastal areas, and we can arrange rapid appointments wherever you are based.

Is excavation better than herbicide treatment?

It depends on your situation. Herbicide treatment is cost‑effective and suitable for most residential properties, but it takes longer. Excavation provides immediate removal and is ideal for construction sites, landscaping projects, or urgent property sales. We advise on the best option after assessing your site.

Can I sell my house if it has Japanese Knotweed?

Yes — as long as you have a professional management plan in place. Most lenders will proceed once a PCA‑approved plan and insurance‑backed guarantee are provided. We work closely with estate agents, solicitors and lenders to keep sales progressing smoothly.

Will my home insurance cover Japanese Knotweed?

Most standard home insurance policies do not cover Japanese Knotweed unless it has already caused damage. However, our treatment plans and guarantees provide the protection lenders and solicitors require, even if your insurer does not.

What happens if my neighbour has Japanese Knotweed?

If the Knotweed is encroaching onto your land, your neighbour may be legally responsible for preventing further spread. We can carry out a CSJK‑qualified survey to document the issue and provide a management plan that protects your property and supports any legal or insurance processes.

Can Japanese Knotweed damage my house?

While it rarely causes structural collapse, it can exploit weaknesses in walls, patios, drains and outbuildings. It spreads aggressively underground and can cause costly damage if left untreated. Early intervention is always the most cost‑effective option.

How long does a management plan last?

Most management plans run for 5 years, with ongoing monitoring and treatment visits included. This duration meets the requirements of the majority of UK mortgage lenders and provides long‑term reassurance for homeowners and buyers.

Do you remove other invasive weeds as well?

Yes. In addition to Japanese Knotweed, we also treat other invasive species such as Himalayan Balsam, Giant Hogweed, Horsetail (Marestail), and Bamboo. Each species requires a different approach, and we tailor our treatment plans accordingly.