Buying a house which you suspect or have been told, has Japanese Knotweed…

The first step is to have a professional survey by a Property Care Association member who is a certified surveyor in Japanese Knotweed (csjk) to initially confirm the presence of Japanese Knotweed.  They will need to assess the extent of the problem highlighting any risks and compile a comprehensive report with a proposed programme of works for remediation. The programme of works will need to be covered by a 10 year Insurance Backed Guarantee, most mortgage companies will require this process in place to proceed.

Once you contact us, we will visit and survey the property and aim to have a report back to you within 3 working days. We will liaise with you estate agent, mortgage lender or solicitor where required.

Should we buy a house with Japanese Knotweed?

Unfortunately, the adverse media attention created over the last few years has given Japanese Knotweed super powers of demolition and a reputation far out weighing its true abilities. The plant’s stigma is far more powerful than the plant itself, Japanese Knotweed has 1000s of chromosomes and is pre-programmed to help its survival, however Japanese Knotweed cannot grow through sound concrete although it will exploit a weakness in concrete or stone etc., potentially causing structural damage.

The existence of Japanese Knotweed on the property, or indeed any adjoining land, should be reported to the mortgage company before exchange of contracts. Each lender has their own views on the matter.  Some will lend provided you promise to sort it out, others will lend if it is under a certain distance from the house whilst some may not lend at all.  

My advice to a buyer would be to identify whether or not there is Japanese Knotweed at the property at an early stage and to put in place a programme to manage it.  This may cost you around £3,000 (average 10 year insurance guarantee programme) but it will save you time and money in the long-term.

Identification Service





If you suspect Knotweed but are unsure, use our free Identification Service. Simply send us a photo and we’ll get back to you.

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