A home inspection is a visual review of the parts of a building that can be reached and seen on the day. That sentence is the whole job, and most misunderstandings come from reading past it. The inspector walks the property, operates what can safely be operated, looks at what is exposed, and writes down what is wrong, what is worn, and what could not be seen.
What is looked at
The usual order runs from the outside in, and from the top down. The letters in the drawing match the list that follows.
- A Roof covering, flashings, chimney, gutters
- B Attic: insulation, ventilation, framing, fan ducts
- C Electrical service and panel, visible wiring
- D Water supply, drains, shut-off valve
- E Furnace or boiler, hot water tank, venting
- F Foundation, crawl space or basement, moisture
- G Grading, downspouts, driveways, retaining walls
- H Windows, doors, cladding, decks
On a detached house that means the roof covering and flashings, gutters and downspouts, exterior cladding, windows and doors, decks and stairs, the foundation as far as it is visible, and the way the lot drains. Inside, the inspector looks at the electrical service and panel, a sample of receptacles and switches, the water supply and drain pipes that are exposed, the water heater, the furnace or other heating, the attic and its insulation and ventilation, and the crawl space or basement if there is access. Floors, walls, ceilings, stairs and railings get a general look for cracks, stains and movement.
Receptacles are tested in a representative number of rooms. Taps and toilets are run. The furnace is started. Windows and doors are opened. None of this is a full performance test, and nothing is taken apart.
What is included and what is not
| Usually included | Usually not included |
|---|---|
| Visible structure: foundation, floor framing, roof framing where accessible | Anything behind finished walls, ceilings or floors |
| Roof covering and flashings, from the roof where it is safe, otherwise from the ground or a ladder | Roofs that are unsafe to walk, and the inside of chimneys and flues |
| Main electrical panel, visible wiring, a sample of receptacles and switches | Low-voltage wiring, alarm systems, and detailed testing of each circuit |
| Exposed water supply and drain pipes, fixtures, water heater | Buried water and sewer lines, and the condition of the municipal connection |
| Heating equipment operated with normal controls | Heat exchanger internals, and ductwork inside walls |
| Attic and crawl space where they can be entered | Spaces that are blocked, sealed, or unsafe to enter |
| Signs of water entry, rot, and moisture where visible | Mould, asbestos, lead and radon testing, and identifying them with certainty |
| Grading, drainage and walkways near the building | Septic systems, wells, pools, and detached outbuildings unless booked |
Why the limits matter
Mould is a good example. We may see a stain that looks like it, or a musty smell in a crawl space, and we say so. But a visual inspection cannot tell you what organism it is or how far it extends. That needs sampling by someone qualified.
The same is true of a sewer line. A drain that runs fine on inspection day can still be cracked or full of roots underground. A camera scan is a separate job, and on older houses with clay or cast iron drains it is worth booking.
Oil tanks, too. We can see a fill pipe or vent pipe outside, or an old tank in the basement. We cannot see a tank buried years ago. The guide on oil tanks covers what to do when a house is old enough to have had one.
Condition, not pass or fail
An inspection does not give a grade. A house is not passed or failed. The report describes the condition of what we could see, ranks the findings by urgency, and notes the limits. Every house has findings, and a long list on an old house is normal. The question that matters is which ones are expensive, which are urgent, and which change what you are willing to pay. The guide to reading your inspection report goes through this.
When a specialist is needed
An inspector is a generalist. When the findings point to something that needs a specialist, the report says so. Common examples are an electrician for a double-tapped breaker or knob-and-tube wiring, a plumber for Poly-B pipe, a roofer for a failing flashing, a drainage contractor for a wet crawl space, and an engineer for a foundation that has moved or a wall that has shifted.
The inspector does not do the repairs. That separation is deliberate. Someone who is paid to fix what they find has a reason to find more.
Things an inspection does not do
- It does not predict how long a roof, furnace or water heater will last. We can say what age and condition we see and what range is typical. See typical component lifespans.
- It does not guarantee that nothing will go wrong after you move in. Conditions change, and some problems only appear in particular weather or with use.
- It does not check compliance with the building code or with municipal bylaws. A house built before a rule existed can be perfectly legal and still not meet today's standard.
- It does not cover the legal status of a secondary suite. Whether a suite is permitted is a question for the municipality and your lawyer.
Attending the inspection
Come if you can. The walk-through at the end, when the inspector shows you the main findings on site, is more useful than the report alone, and you will remember what a roof valley or a wet crawl space actually looked like. Bring your questions. If you have seen the strata documents or the seller's disclosure, bring them too.
If you cannot come, read the report carefully, and phone the inspector with questions before your subject date.