The HSS is very prescriptive of the methodology and the manner of the level of expectation of inspection for the inspecting surveyor.
Windows
Attempt to open all windows where possible.
Roof space
The RICS member will enter the roof space and visually inspect the roof structure, with attention paid to those parts vulnerable to deterioration and damage. Although thermal insulation is not moved, small corners should be lifted so its thickness and type, and the nature of the underlying ceiling, can be identified (if the RICS member considers it safe to do so). Where permission has been granted and it is safe, a small number of lightweight possessions should be repositioned so a more thorough inspection can take place.
Floors
The RICS member will inspect the surfaces of exposed floors and will lift the corners of any loose and unfitted carpets or other floor coverings where practicable. The RICS member will assess all floors for excessive deflection by a ‘heel-drop’ test. For a more complete assessment, the magnitude of any identified deflection/slope should be measured. Where the subfloor is inspected, an inverted ‘head and shoulders’ inspection will be carried out at the access point (either physically or using mirrors, cameras and the like). If it is safe to do so, the RICS member will enter the under-floor area to carry out a more thorough inspection.
Inspection chambers and underground drainage
The RICS member will lift accessible inspection chamber covers to drains and septic tanks (where it is safe to do so and without causing damage) and observe the normal operation of the drains in everyday use. This will be restricted where properties are empty and drained down. Where the RICS member considers it appropriate for the assessment of the system, and where practical, ‘everyday use’ will usually include turning on water taps to sanitary ware and flushing toilets so the performance of visible drainage pipework can be observed and the nature of the belowground connections identified.
Other
In addition to those actions described under ‘Inspection chambers and underground drains’, the RICS member will observe the normal operation of the services in everyday use (where it is safe to do so and without causing damage), including operating an identified sample of lights and extractor fans and asking the occupier to operate the heating.
Grounds
As in level two, the RICS member should perform a comprehensive inspection of the grounds, noting any limitations. Specific defective features and other matters associated with the grounds can be costly to resolve and may affect the client’s decision. Consequently, the RICS member should fully account for these during a level three service and be prepared to follow the trail of suspected problems to a greater extent than at levels one and two. Examples include assessing retaining walls in danger of collapsing, deeply sunken paths or driveways, and dilapidated boundary walls or fences, as well as the legal and insurance implications.
As you will note, this will take time and the HSS is very prescriptive of the methodology of inspection. It should be noted that the HSS sets the bare standard minimum for compliance with the standards expected by RICS.