What does a home inspector actually check?

A home inspection is a visual, non-invasive examination of a building’s readily accessible systems and components, carried out to a published standard of practice. That definition is doing a lot of work — particularly the words visual, non-invasive and accessible. Here is what that means in practice, room by room and system by system.

Roof and attic

The inspector assesses covering material and its remaining service life, flashings at every penetration and transition, valleys, the chimney and its cap and crown, plumbing and exhaust vents, and gutters and downspouts including where they discharge. Inside the attic: insulation type, depth and coverage, ventilation at soffit and ridge, framing condition, evidence of past or active leakage, and whether bath and kitchen exhausts terminate outdoors or — very commonly — into the attic itself.

A good inspector walks the roof when it is safe and accessible. When it is not — steep pitch, wet or icy surface, height, or fragile covering — the alternative is binoculars, a pole camera or a drone. What matters is that the report says which method was used.

Structure and foundation

Foundation type and condition, visible cracking and what kind it is, evidence of movement or settlement, moisture entry, sump pit and pump operation, and the framing that is visible from the basement or crawlspace — beams, columns, joists, and any modifications made to them. Above grade, the inspector is reading floors for slope, doors and windows for racking, and walls for the diagonal cracking that indicates something has moved.

Not every crack is a problem. Shrinkage cracking in a poured foundation is nearly universal and usually benign. Stair-step cracking through block, horizontal cracking with inward displacement, or diagonal cracks that widen at one end are a different conversation.

Electrical

Service size and entrance condition, panel make and interior, breaker sizing against conductor size, grounding and bonding, branch wiring type, GFCI protection where required, AFCI where applicable, and a representative sample of outlets, switches and fixtures. The inspector opens the panel — if yours does not, that is a serious omission.

Specific things that matter in Ottawa: knob-and-tube in pre-1950 homes, aluminum branch wiring in homes built roughly 1965 to 1977, Federal Pacific Stab-Lok panels, 60-amp services, and double-tapped breakers from later additions.

Plumbing

Supply piping material and condition, drain, waste and vent piping, functional flow with several fixtures running at once, functional drainage, water heater type, age, venting and relief valve, visible leaks and corrosion, fixtures and their operation, and the location of the main shut-off. Materials matter: galvanized steel is at end of life anywhere it survives, and poly-B — common in homes built roughly 1985 to 1997 — is an insurance question as much as a plumbing one.

Heating, cooling and ventilation

Heating equipment type, approximate age, condition, venting and combustion air; distribution through ducts or piping; thermostats and controls; air conditioning or heat pump, its age and its performance under operation; and ventilation including HRV or ERV where fitted, bath fans, range hood and dryer venting. An inspector should be taking temperature readings, not just listening for the furnace to fire.

Interior, exterior and site

Interior: walls, ceilings and floors, windows and doors and their operation, stairs and handrails and guards, garage including the fire separation to the house and the automatic opener’s safety reverse, and smoke and carbon monoxide alarms.

Exterior: cladding, trim, soffit and fascia, windows and doors from outside, decks, porches, steps and railings, walkways and driveway, and retaining walls.

Site: grading and how water moves away from — or toward — the foundation, drainage, and vegetation in contact with the building. Grading is the single most under-appreciated item on the list, and it causes more basement water than any other single factor.

What a home inspection does NOT cover

This list is as important as the one above, and any inspector who is vague about it is doing you harm.

• Anything concealed. Inside walls, under floors, behind stored belongings, beneath insulation, or buried in the ground.
• Anything requiring dismantling. The inspector does not take apart the furnace, lift shingles or open plumbing.
• Sewer laterals. Buried and invisible — this needs a separate camera inspection.
• Wells and septic systems. Separate specialist assessments.
• Environmental hazards. Asbestos, lead, mould, radon and air quality are outside a standard inspection. An inspector should flag suspect materials and offer testing, but the standard scope does not include them.
• Pests and wood-destroying insects. Evidence is noted; the inspection is not a pest inspection.
• Code compliance. An inspection is not a code inspection, and buildings are generally judged against the code in force when they were built.
• Value, or predictions of the future. Not an appraisal, and not a warranty against future failure.

The professional standards of practice published by bodies such as InterNACHI, CAHPI and OAHI define these boundaries in detail, and your inspection agreement should reference the standard being followed.

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