What Happens at a Home Inspection: A Plain-Language Guide for London, Ontario

A home inspection is a check-up for a house, the same way a doctor gives you a check-up. A home inspector walks through the home, looks closely at the big parts that keep it dry, warm and safe, and then writes down what they found. The inspector's job is not to pass or fail the house. Their job is to help you understand what you are buying, so there are fewer surprises after you move in.

This guide explains what the inspector looks at, step by step, in plain words. It is written for homes in London, Ontario and the towns and farms around it in Middlesex and Elgin counties.

Before and during the inspection

When it happens. In Ontario, most buyers make their offer "conditional on a home inspection." That means you get a few days, set out in your agreement, to have the house checked before the deal becomes firm. Your real estate agent writes this into the offer. Some buyers inspect before making an offer instead, especially when several people want the same house. Your agent can explain which approach fits your situation.

How long it takes. Plan on about two to four hours for a typical house. Bigger or older homes take longer.

Come along if you can. You will learn more by walking through the house with the inspector than by reading the report alone. Wear comfortable shoes and bring your questions.

The inspector looks, but does not take things apart. A home inspection is a visual inspection. The inspector looks at what they can see and safely reach. They open panels that are meant to be opened, turn on taps, and run the furnace. They do not cut holes in walls, lift up floors, or move the seller's furniture. If something is hidden, the inspector can only report the clues they see, like a water stain on a ceiling.

The season matters. In fall and winter, snow or ice can make a roof unsafe to walk on, so the inspector may check it from a ladder or the ground. Air conditioners should not be run when it is cool outside (usually below about 15°C), because it can damage them. If the inspector cannot test something, the report will say so.

Outside: the house's raincoat and boots

The inspector usually starts outside, because most problems in a house begin with water getting where it should not.

The roof. Think of the roof as the house's raincoat. Most roofs around London use asphalt shingles, which usually last about 15 to 25 years. The inspector looks for shingles that are curling, cracked, missing, or losing their little gritty granules. They also check the metal pieces around the chimney, vents and skylights, called flashing. Flashing is like the seal around a window, and leaks often start there.

Gutters and downspouts. Gutters catch rain and send it down the downspouts. The downspouts should carry water at least a metre or two away from the house. If they dump water right beside the wall, it can soak into the basement. In London, homes are generally not allowed to drain downspouts into the sewer system, so they should empty onto the lawn instead.

The ground around the house. The soil should slope away from the house, like a gentle hill, so rain runs off instead of pooling against the walls. Flat or backward-sloping ground is one of the most common causes of wet basements that inspectors find.

The foundation from outside. The foundation is what the house sits on, like its boots. The inspector looks at the parts that show above the ground for cracks, crumbling, or bulging. Small, thin cracks are very common as concrete dries and settles. Wide cracks, cracks shaped like stairs, or walls leaning inward are signs the inspector will suggest a specialist look at.

Walls, windows and doors. The inspector checks the brick or siding, the caulking around windows and doors, and whether decks, porches and railings are solid. Loose railings and steps are a safety issue, especially for kids.

The attic: letting the house breathe

If there is a safe opening, the inspector looks into the attic. They will not crawl across it if that could damage the ceiling below, but a lot can be seen from the hatch.

Insulation. Insulation is the house's winter coat. The inspector checks that there is enough of it and that it is spread evenly. Many older homes in London have much less than newer homes built under today's Ontario Building Code.

Ventilation. An attic needs to breathe. Fresh air should come in low, usually through vents under the edge of the roof (the soffits), and warm, damp air should leave high, through roof vents or a ridge vent. The Ontario Building Code sets a minimum amount of vent opening for this. When air cannot move, two problems show up:

• In winter, warm air melts snow on the roof. The water refreezes at the cold edge and builds a ridge of ice, called an ice dam, which can push water under the shingles.
• Damp air gets trapped and can cause frost, mould, or dark stains on the roof boards.

Bathroom and kitchen fans. These fans should blow outside, not into the attic. A fan venting into the attic is like breathing into a closed bag. It is a common, fixable problem.

Signs of leaks or pests. The inspector looks for water stains on the wood and for droppings or nests from mice, squirrels, raccoons or birds.

The equipment: the house's heart, lungs and veins

These are the machines and systems that keep the house running. The inspector turns them on with their normal controls and watches how they work.

Furnace. Most homes here heat with a natural gas furnace. The inspector checks that it turns on, heats properly, has a clean filter, and vents its exhaust safely to the outside. Furnaces often last about 15 to 20 years, so the report will note roughly how old yours is. A gas-fitter should service it once a year.

Air conditioner. The inspector checks its age and condition. As mentioned above, it is only run when the weather is warm enough.

Water heater. The inspector checks its age, looks for rust or leaks, and makes sure it has a safety valve and drain pipe. In Ontario, many water heaters are rented rather than owned. That means a monthly bill that may transfer to you. Ask your agent to confirm this before you buy.

Plumbing you can see. The inspector runs taps, flushes toilets and fills sinks and tubs to check water pressure and draining. They look under sinks for drips, check the main water shut-off, and look at the visible pipes for leaks or old materials.

Electrical panel. The panel is the box full of switches (breakers) that controls power to the house. The inspector opens the cover, which is designed to come off, and looks for overheated parts, messy or unsafe wiring, and whether the service size (often 100 amps in older homes) fits the house. They also test a sample of outlets. Outlets near water, like in bathrooms and kitchens, should have special safety outlets called GFCIs that shut off quickly if something goes wrong.

Smoke and carbon monoxide alarms. Ontario's Fire Code requires a working smoke alarm on every floor and outside every sleeping area. If the house has a gas furnace, gas fireplace, wood stove or attached garage, it also needs carbon monoxide alarms outside the sleeping areas. The inspector checks that they are there; you should test them and change batteries when you move in.

The basement and foundation from inside

The basement tells the inspector a lot about how well the house handles water.

Moisture clues. The inspector looks for water stains, white chalky powder on concrete walls (called efflorescence, a sign water has passed through), musty smells, rust on metal, and peeling paint near the floor. They may use a moisture meter on surfaces they can reach.

Foundation walls and floor. Where the walls are not covered, the inspector looks for the same cracks, bulges and leaning they checked outside. If the basement is finished with drywall, they can only see the clues around the edges.

Sump pump and backwater valve. Many London homes have a sump pump, a small pump in a pit that pushes groundwater out of the house. The inspector checks that it runs and discharges outside. Some homes also have a backwater valve, a flap in the main drain that stops sewer water from backing up into the basement during big storms. If there is one, the inspector checks that you can get to it for cleaning.

What an inspection does not cover

A home inspection is a careful look, not X-ray vision. It does not include:

• Anything inside the walls, under the floors, or behind finished ceilings
• A check of whether past renovations had building permits (your lawyer or the municipality can help with this)
• Testing for mould, asbestos, lead or radon in a lab
• Pools, hot tubs, sprinkler systems, or how long each item will last exactly
• A guarantee that nothing will ever go wrong

If the inspector sees something that needs a closer look, they will tell you which kind of specialist to call, such as a licensed electrician, roofer, plumber or foundation contractor.

The report and what to do next

Within a day or two, you will get a written report with photos. It sorts what the inspector found from serious safety or cost concerns down to small, everyday upkeep. Every house has a list, even brand-new ones. The goal is to know which items matter.

Read the report with your real estate agent. Together you can decide whether to go ahead, get a quote from a contractor, ask the seller about a repair, or adjust your plans. Calm, informed decisions are what an inspection is for.

Choosing an inspector. Ask about training, experience, and membership in a professional group such as the Ontario Association of Home Inspectors (OAHI). Ask to see a sample report, and confirm they carry insurance.