Further investigation means the home survey did not provide enough evidence for a reliable conclusion on a material issue, or specialist testing falls outside scope. It requests better information, not automatically confirmation of severe defect.
RICS expects further work where reasonable confidence cannot be achieved. The recommendation should be proportionate and explain what question needs answering.
Why uncertainty remains
Construction may be concealed or access restricted. Services need specialist testing, drains are underground and movement may require measurement or engineering analysis.
A surveyor should not guess. Stating limitation and next investigation is better than unsupported diagnosis.
Match expert to question
Specialists may include engineers, electricians, heating engineers or drainage contractors. Consider independence where the specialist also sells treatment.
The brief should identify the evidence and required outcome; a generic quotation may not answer the question.
Timing and permission
Investigate before exchange where the answer could affect safety, cost or willingness to buy. Opening-up needs owner permission.
If access is refused, discuss residual risk with surveyor and conveyancer.
- What prompted the recommendation?
- What must be established?
- Who is qualified?
- Is testing permitted?
- Is the answer needed before exchange?
Use the result
Send written findings to the surveyor where interpretation is needed, and obtain repair quotations once cause and scope are understood.
Pass approvals and responsibility to the conveyancer. In England and Wales, use combined evidence before exchange.
Retain the specialist’s scope, photographs and conclusions with the survey. If the specialist could inspect only part of the concern, make sure the outstanding limitation is visible in your decision record rather than assuming that commissioning the appointment resolved every associated risk.
Avoid investigations that do not answer the question
More testing is not automatically better. Each recommendation should have a defined purpose, such as determining whether cracking is active, confirming the condition of concealed drainage or establishing whether an electrical installation is safe for continued use. Ask the specialist to address that purpose in writing, record the methods used and explain any remaining limitations. This creates evidence that can genuinely inform the purchase.
Be cautious where an investigation is offered free only on condition that the same business supplies a treatment. That does not make the advice wrong, but the commercial interest should be understood. For complex dampness, movement or structural concerns, an appropriately qualified independent professional may provide a more balanced basis before repair contractors are asked to price solutions.
Ask whether the investigation needs access from the seller, managing agent or neighbouring land and whether surfaces will be disturbed. Agree responsibility for making good before work begins. If the investigation cannot be completed within the transaction, request a written explanation of what remains unknown and consider that uncertainty alongside the likely worst credible consequence.
Advice for your property
Get the right professional inspection
Online guidance is useful, but it cannot account for the construction, condition and history of an individual property. Tell us what you are buying or need valued and we will explain the appropriate service.
Authoritative sources and further reading
The guide is general information, not property-specific, structural, legal, tax or financial advice. Source pages can change; consult the relevant professional for your circumstances.