Air Duct Cleaning Cost in London, Ontario — What You'll Actually Pay

Few home services have as wide a spread between legitimate pricing and bait-and-switch pricing as duct cleaning. You'll see ads for $89 whole-house cleaning. You'll also get quotes for $700. The frustrating part: both can be "real" prices — they just describe completely different services.

This post gives you the actual cost ranges for proper air duct cleaning in London, Ontario, explains what drives the price, and shows you exactly what separates a legitimate quote from a low-ball that will inflate at your front door.

What a Complete Duct Cleaning Actually Involves

Before you can evaluate a quote, you need to know what professional duct cleaning should include. A legitimate service covers:

• All supply ducts: The ducts that carry heated or cooled air from the furnace to each room. This is the largest portion of your ductwork system and the most time-consuming to clean.
• All return air ducts: The ducts that carry air back to the furnace from your living spaces. These are often larger-diameter and accumulate significant dust.
• The main trunk: The large central duct running from the furnace through the house. Everything connects here, and it accumulates the most debris.
• The furnace air handler: The blower and housing inside the furnace itself where dust, pet dander, and debris collect over time.
• Supply and return registers: Cleaning the covers and the duct opening at each register.

A legitimate duct cleaning uses a truck-mounted or commercial-grade vacuum system that creates negative pressure in your ductwork — pulling debris toward the collection point rather than blowing it through your home. Technicians also agitate deposits with brushes or compressed air tools before vacuuming.

What the Price Ranges Actually Look Like

Home Type	Typical Cost (CAD)	What Drives the Range
Small home / condo (1–2 bedrooms, 1 furnace)	$350 – $480	Fewer ducts, smaller square footage, simple trunk layout
Medium home (3–4 bedrooms, 1 furnace)	$450 – $620	Average London home — this is the most common range
Large home (4+ bedrooms, 1 furnace)	$550 – $750	More supply and return ducts, longer trunk runs
Any home with 2 furnaces / 2 zones	Add $200 – $350	Second system is essentially a separate job
Dryer vent cleaning (add-on)	$80 – $150	Strongly recommended; separate from ductwork
Furnace cleaning (add-on)	$100 – $180	Blower wheel, heat exchanger cleaning; separate service

What Drives the Cost Up in London Homes

Home Age and Ductwork Condition

London has extensive pre-1970 housing stock — particularly in Old South, Wortley Village, Byron, and the older east-end neighbourhoods. Older homes often have galvanized steel ductwork that's been accumulating debris for decades. First-time cleanings on homes that have never been serviced take longer and may cost 20–30% more than routine maintenance cleanings.

Number of Vents and Returns

Most companies price based on vent count or square footage. A 2,200 sq ft home with 18 supply vents and 4 returns is a different scope than a 1,100 sq ft home with 10 vents and 2 returns. Get specifics when comparing quotes — "whole house" means different things.

Accessibility

Ducts in finished basements, under low ceilings, or in tight crawlspaces take longer to access and clean. Homes with unusual ductwork layouts (octopus-style systems common in older London houses) may require more time for thorough coverage.

Contamination Level

Standard dust and debris: normal pricing. Mold growth in ductwork: expect biocide treatment to be recommended, which adds $100–$300+ and is a legitimate additional cost. Rodent or pest intrusion: remediation before cleaning, significant additional cost. Construction debris (post-reno): more intensive cleaning, higher cost.

Add-On Services

Dryer vent cleaning and furnace cleaning are separate services that most companies offer alongside duct cleaning. They're worthwhile (dryer vents are a fire risk; furnace cleaning extends equipment life), but they're legitimately add-ons — not something that should quietly appear in a "whole house" quote.

The Bait-and-Switch: How It Works and How to Spot It

This is the most important section for London homeowners to read before booking. Duct cleaning has a well-documented bait-and-switch problem: companies advertise unrealistically low prices to book appointments, then dramatically inflate the bill once they're in your home.

Here's how the scam typically plays out:

1. You see an ad for "$89 whole-house duct cleaning" or "$99 special."
2. They arrive and quickly "discover" that your ducts need additional services — sanitizing treatment, extra vents, "heavy contamination" charges.
3. By the time they're done quoting the real job, you're at $400–$900 and feel pressured to proceed because they're already there.
4. Sometimes they do minimal work at the low price and leave — which is arguably worse because you paid for nothing useful.

How to Get an Honest Quote in London

Getting a real number before booking requires asking the right questions:

• "What exactly does your quoted price cover?" — Confirm supply ducts, return ducts, trunk, and air handler are all included.
• "Is that your full price, or are there add-ons once you arrive?" — A legitimate company will confirm the all-in price or tell you what scenarios would change it.
• "How many supply vents and returns does the price assume?" — Let them verify against your actual home, then confirm the total before booking.
• "Do you carry NADCA certification or equivalent professional credentials?" — Not the only quality signal, but a meaningful one.
• "Do you use truck-mounted equipment or portable vacuums?" — Truck-mounted creates better negative pressure. Portable units can do adequate work but aren't the industry standard for thorough cleaning.

Is Duct Cleaning Worth the Cost?

Done properly by a legitimate company, yes — with context. Air duct cleaning does not cure allergies or dramatically reduce airborne particles on its own (HVAC filters are your main line of defence there). What it does do:

• Remove accumulated dust, debris, pet dander, and biological material from the air distribution system
• Restore airflow through ducts that have significant buildup
• Allow visual inspection of ductwork for issues (flex duct disconnections, mold, pest intrusion) that might otherwise go undetected
• Provide a baseline clean for homes after renovation or purchase

The NADCA recommends cleaning when you observe visual contamination, after renovation work that generates significant dust, after a mold or pest problem, or when you're moving into a home with no cleaning history. Not necessarily on a rigid schedule for every home.

London's older housing stock, long heating season, and agricultural particulates in the air (especially for homes near agricultural land east and southwest of the city) do create genuinely higher duct contamination over time than many Canadian cities.