Japanese knotweed

If knotweed is visible, does the 2022 RICS journal still expect a specialist recommendation?

Yes. The journal says that in all cases there will be a recommendation for the client to obtain advice from a remediation specialist. That includes the lower categories. The recommendation is advice, not an order to excavate before exchange.

Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.

What is the fuller explanation?

“All cases” in that article means the surveyor should point you to a specialist, not that every case has the same works. Category C and category D were not expected, in the journal’s words, to trigger the same lender retention as A or B. You still get a name and a reason to take advice. The specialist may say “manage” or “you cannot treat the neighbour’s land”.

Choose a firm that will identify the plant and write a plan. Ask whether any guarantee is insurance-backed and whether it transfers. Do not pay for herbicide spraying from an unnamed van because the survey used the word knotweed. Government guidance explains the duty not to spread the plant. The specialist should follow that. There is no set call-out fee in the RICS standard.

What should you ask your surveyor?

Is your recommendation a specialist’s advice, or a specific treatment?
Which category sits behind that recommendation?
What should the specialist look at that you could not, including land you could not enter?

What are the typical next steps?

Get the advice in writing before you agree a price cut that pretends to be a treatment cost.
If the specialist disagrees with the category, put both documents in front of the lender rather than averaging them.
Do not delay asking just because the category is C or D. The journal’s point is that the recommendation is still made.

Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.

Also asked about this

Can the home surveyor also be the remediation firm?

Only if that is a separate instruction and you understand the two roles. The journal is describing a recommendation to a specialist, not a treatment sold inside the survey fee.

What if the surveyor only says “possible knotweed”?

Then identification is the first specialist job. Do not pay for a full excavation plan until someone competent has said it is the plant.