Mold Inspection Cost in London, Ontario: Test and Removal Prices

A residential mold inspection with lab-analyzed sampling in London generally runs $300 to $600, and a mold test on one patch runs $250 to $400. We publish that on purpose, because almost nobody in this market will, and the vagueness is where people get taken. If the result points to remediation, mould removal in London, Ontario explains how to size the job before quotes come in.

An independent test is the cheaper mistake to make: Health Canada frames mould as a moisture problem to identify and fix, and the EPA agrees, so a lab-backed inspection that finds the source is what stops you paying for a remediation you may not need. This page breaks down what moves the price, what a "free inspection" actually costs you, and honest ranges for the removal that testing sometimes leads to.

How much is a mold test on its own?

If you only want one thing identified, you do not need to pay for a whole-house inspection. A single-patch identification, one surface sample to name the growth and one air sample to see whether indoor levels are elevated against outdoors, runs $250 to $400 in London. Extra samples are $75 to $150 each. That is the honest answer to "how much is a mold test": a few hundred dollars with the accredited lab included, not the $30 of a hardware-store kit and not the "free" of a removal company's sales visit.

Health Canada's own advice is that in most cases there is no need to measure mould in the air or name the species. So before you pay for any test, be clear what you need it for: documentation for a sale, a dispute or an insurer, finding hidden growth behind a musty smell, or a clearance after removal. If none of those applies, a small patch with a known cause can be cleaned and the moisture fixed, and the test is optional.

Mold testing and removal cost, added up

People searching for the combined number usually want to know the worst case before they start. Here it is, built only from the ranges on this page:

Two things keep the real number toward the bottom of each row. An independent test before removal defines the job, so contractors price the same scope instead of their own. And a clearance test from someone other than the remover means you pay for the work once. In a pre-1990 house, add an asbestos check before walls open; it is cheap next to the removal it protects.

Mold assessment, mold evaluation, mildew inspection: same price?

Yes. "Mold assessment", "mold evaluation" and "mold inspection" are different names the industry uses for the same visit: a walk-through, moisture readings and lab sampling where it helps. In London they fall in the same $300 to $600 band. If one company quotes an "assessment" and another an "inspection", ask the same three questions of both: how many samples, which lab, and do they also sell the removal.

Mildew is a different case. It is the surface mould that grows on bathroom caulking, shower grout and window sills where condensation sits. It is usually small, its cause is obvious, and Health Canada's cleaning advice covers it: soap and water, dry the area, fix the ventilation. Paying for a lab to name mildew on a shower seal is rarely money well spent, and we will tell you that on the phone. It becomes worth testing when the "mildew" keeps returning after cleaning, spreads beyond the wet area, or comes with a musty smell from somewhere you cannot see.

Why quotes and "free inspections" vary so much

Two things drive the confusion in this market, and both are worth understanding.

The "free inspection". A free mold inspection is a sales call. It costs you nothing at the door because the company expects to make its money on the removal quote that follows, which gives every incentive to find a big problem. Our inspection is not free, and that is exactly why you can trust what it finds.

Samples in or out. Some low quotes cover a visual look with no lab work, which is close to worthless for a mold question, because the whole point is the lab identifying what is there. A $150 "inspection" with no samples and a $450 inspection with lab analysis are not the same product. Ask what is included.

What moves the price up or down

• Home size and number of areas of concern: more square footage and more trouble spots mean more samples.
• Whether there is visible growth to identify versus an air-quality concern with nothing visible, which changes the sampling mix.
• Post-flood scope: a basement that took on water usually warrants more sampling than a single bathroom patch.
• Rush: when a real estate closing or a tenant dispute cannot wait, expedited lab turnaround adds a modest surcharge.
• Access: a finished, sealed basement or a hard-to-reach attic can add time.

None of these are surprises sprung on you mid-visit. They are the questions we ask on the phone to give you a firm number.

What removal costs, so you're not blindsided

We do not do removal, but you deserve honest ranges so the word "remediation" is not a blank cheque. In the London market, remediation typically runs:

• A small, contained area (a bathroom patch, a section of drywall): roughly $500 to $1,500.
• A moderate job (a section of finished basement, an attic): roughly $2,000 to $6,000.
• A large or whole-basement remediation after significant water damage: $6,000 to $15,000 or more, often overlapping with water-damage restoration.

These are the contractor's numbers, not ours, and the value of an independent test is that it defines the job so those quotes are comparable and honest. Our guide to hiring for mold removal in London covers what a sound quote should contain. Run your own situation through the do-I-need-a-test triage if you are still deciding.

Is it worth it?

For a few hundred dollars you get certainty on a question that otherwise drives either needless spending or nagging worry. If you are buying a house, it is trivial next to the purchase and gives you negotiating leverage. If you are a landlord or tenant, it is the document that settles the argument. If you are simply worried, it is the fastest way to stop worrying, in either direction.

Common questions