Condition ratings
What should a “further investigation” sentence include before you book anyone?
It should say what is suspected, where, and which kind of specialist is needed. RICS uses further investigation when the surveyor cannot conclude from the inspection. It is not a condition rating by itself. A sentence that only says “further investigation recommended” is a reason to ask the surveyor to specify the trade and the question, not a reason to instruct three firms at random.
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?
The Level 3 description says that where the surveyor is concerned about parts they could not fully inspect, the report tells you about further investigations, and that if they suspect a problem they recommend one. The rating beside that sentence still matters. Rating 3 adds that defects which are serious or need urgent investigation should have written quotations before you are legally committed. A vague referral does not meet that purpose until the scope is clear.
Email the firm and ask: who should do it, what should they open, and what decision it is meant to unlock. Then instruct that person. Do not pay for a damp survey, a drain camera and a structural engineer because one sentence named none of them. There is no RICS fee for “investigation” as a lump. Each specialist quotes their own scope.
What should you ask your surveyor?
- What question do you want the specialist to answer?
- Which element and which rating does this sentence belong to?
- What access will they need that you did not have?
What are the typical next steps?
- Get the scope in writing before you compare specialist quotes.
- Do not treat the investigation as optional if it sits under a rating 3 and you intend to proceed.
- Do not commission it for a rating 1 the surveyor has already cleared.
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
Is further investigation the same as NI?
No. NI means not inspected. Further investigation means the surveyor thinks a specific doubt needs a specialist. A limit with no concern is not the same sentence.
Can you do the investigation after completion?
You can, but you will own the result. The Level 3 wording on rating 3 is about quotations before legal commitment. After completion the seller has usually gone.