Knotweed Reports, Surveys and Certificates

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We have personal experience of situations whereby property exchange has suffered considerable delay and upon occasions, the prospective purchaser withdrawing an offer purely due to a surveyor or estate agent, whilst having the best intentions have incorrectly identified a plant as Japanese Knotweed.

The simple truth is that some professionals will recognise Knotweed instantly whilst others have little or no real knowledge of plant features. Knotweed can be notoriously difficult to spot during the winter months, especially if the dead canes from previous season’s growth have been cut or the infestation is not as yet, well-established. Having liaised with numerous surveyors & estate agents over the last few years, it is apparent that just like the UK mortgage lenders, a ‘no-risk’ stance has been adopted. Understandably, to avoid the prospect of future litigation, on occasions where there is uncertainty that Knotweed does or does not exist on a property, the professionals involved in the process, consider it is far more prudent in the long-term to stipulate it ‘may exist’ as opposed to omitting any declaration of the plant on a Homebuyers Survey Report. In following this course of action, the surveyor / organisation avoids legal action down the line!


Validation Report


In the foregoing circumstances, we can conduct a site visit, purely in order to confirm or negate that a particular plant is or isn’t Knotweed and dependent on the location, there will normally be no fee involved (this can also be achieved with use of relevant photographs). Verbal confirmation in the presence of the client or prospective purchaser will often suffice although if we are initiated following a directive from a mortgage lender, we can confirm this officially in writing whilst providing an estimate of potential remedial work.

It must be pointed out that whilst we will document our findings as accurately as we can, we can’t, under any circumstances, categorically confirm 100% whether Knotweed material does not exist on a particular site. This is purely due to the fact that even though there may be no visual indication, Knotweed can quite easily be concealed by cutting down, excavated, burned or covered over etc. especially outside of the growing season. It is impossible to see what lies beneath the surface hence our assessment, will only represent what we have seen. Rest assured however, we will be meticulous.

Site Assessment Report


On the whole, the rationale of a SAR is to provide clear guidance to the mortgage lender or purchaser regarding the level of risk involved due to the existence of Knotweed on or close by to a particular property. We will provide a summary of treatment options, map out locations or special features and confirm whether any Knotweed has damaged or has the scope to damage any permanent structures within the property. The content of the SAR will normally be analysed by the mortgage lender, in order to form a sound basis of whether under their own individual protocols, there is or isn’t a significant risk in lending.

Japanese Knotweed Management Plan (JKMP)

A JKMP is essentially a detailed document that illustrates how we as the contractor, can outline the appropriate methods of treatment. The plan will contain information relating to the severity of contamination on site, an evaluation of control options, detailed assessment of the risks associated with any control action & advice on biosecurity. The JKMP will be updated annually following treatment & evaluation.

We provide JKMP’s for residential properties, building plots which will be subject to housing development and larger scale development projects. A JKMP involving a development site will contain far more detailed information that say, a 2 bedroom residential property. Generally speaking, a JKMP will usually be required by the mortgage lender, prior to an agreement being made to provide funds for property purchase. All our JKMP’s are supplemented by a 10 year Insurance Backed Guarantee (IBG). The JKMP ‘stays’ with the property, meaning whenever there is any future property transfer, the JKMP becomes the possession of the new owner irrespective of how many times the property exchanges hands.

Insurance Backed Guarantee (IBG)

All our JKMP’s are supplemented by a 10 year IBG. In simple terms, the IBG provides you as the client, the added assurance that in the unlikely event SWKR cease trading, the IBG will ensure that another accredited contractor will be initiated to carry out any remaining remedial work, at no additional cost.  Furthermore, should the Knotweed resurface from the original infestation site within 10 years of SWKR issuing the Completion Certificate (see below) to the property owner, we shall return to complete the remedial work, or if we are no longer trading, another accredited contractor will be paid to complete the work.

Completion Certificate

A Completion Certificate is just that – a certificate of completion! Whenever overall control is achieved following several years treatment in line with the JKMP, we shall issue the completion certificate once there is clear evidence of 2 years no regrowth.