Let's review the InterNACHI® Home Inspection Standards of Practice related to a particular part of a house - the roof.
According to the InterNACHI® Home Inspection Standards of Practice, the home inspector shall inspect from the ground level or the eaves:
the roof-covering materials;
the gutters;
the downspouts;
the vents, flashing, skylights, chimney, and other roof penetrations; and
the general structure of the roof from the readily accessible panels, doors, or stairs.
The inspector shall describe the type of roof-covering materials.
The inspector shall report as in need of correction observed indications of active roof leaks.
The inspector is not required to:
walk on any roof surface.
predict the service life expectancy.
inspect underground downspout diverter drainage pipes.
remove snow, ice, debris, or other conditions that prohibit the observation of the roof surfaces.
move insulation.
inspect antennae, satellite dishes, lightning arresters, de-icing equipment, or similar attachments.
walk on any roof areas that appear, in the inspector's opinion, to be unsafe.
walk on any roof areas if doing so might, in the inspector's opinion, cause damage.
perform a water test.
warrant or certify the roof.
confirm proper fastening or installation of any roof-covering material.