These two documents are confused more often than any other pair in a house transaction, and the confusion is expensive because each answers a question the other cannot. A survey is about where the parcel is. An inspection is about what condition the structure on it is in.
What a survey establishes
A land surveyor reconstructs the position of a parcel's boundaries on the ground from the recorded description and from physical evidence: monuments set by earlier surveyors, fences, walls and other long-standing occupation. Reconstruction is the right word. The boundary is a legal line described in words and on a recorded map, and finding where those words fall in the dirt is a professional judgement supported by measurement.
The resulting plan shows the boundary lines, the monuments found or set, the position of the improvements relative to those lines, and anything that crosses them. It is the only document that can tell you whether the wall is on the line, over it or short of it.
Encroachment, easement and setback
- Encroachment. A physical improvement that crosses a boundary, whether the neighbour's shed on this parcel or this parcel's driveway on the neighbour's.
- Easement. A recorded right for someone else to use part of the parcel for a defined purpose, commonly utilities, drainage or access. It does not transfer ownership but it does constrain what can be built.
- Setback. A minimum distance from a boundary within which building is not permitted, imposed by the applicable code or by recorded restrictions rather than by the boundary itself.
- Monument. A physical marker placed to memorialise a corner. Its presence, absence or disturbance is a large part of what a surveyor is looking for.
What an inspection covers
A building inspection is a visual, non-invasive assessment of the accessible parts of the structure and its systems: roof covering and drainage, exterior envelope, foundation as far as it can be seen, structure, insulation and ventilation, and the heating, cooling, electrical and plumbing installations. The output is a description of observed condition and of items that appear to need attention.
In a desert climate a competent inspection pays particular attention to roof and envelope exposure, to cooling equipment and its ducting, to irrigation and drainage away from the structure, and to movement in slabs and walls, since expansive and collapsible soils behave differently under wetting.
What an inspection is not
It is not a warranty, not a code compliance certificate, not an engineering analysis and not a valuation. Inspectors do not usually open walls, lift fixed floor coverings or dismantle equipment, and the report's scope statement will say so. Anything concealed is outside it by definition.
When a report flags something as beyond its scope, that is not a hedge. It is the document telling the reader which specialist question has now been raised.
Reading the two together
The survey and the inspection intersect at exactly the points where the building meets the land: an addition built over a utility easement, a wall standing on a neighbour's ground, drainage directed onto an adjoining parcel. These are the problems that neither document alone will surface, because each looks competent within its own scope.
Anyone reading both should read them for that intersection specifically.