Why Kitchen Exhaust Duct Cleaning Is Important
Most restaurant owners see their hood filters every day. What they don’t see is the ductwork behind them, running up through the ceiling and out to the roof fan. That’s where grease quietly builds up, and it’s where the most dangerous kitchen fires spread.
Kitchen exhaust duct cleaning isn’t a cosmetic job. It’s fire prevention, code compliance and insurance protection rolled into one. Here’s why it matters, how often it needs to happen, and what to watch for between cleanings.
What Happens Inside Your Kitchen Exhaust Ducts
Every time you fry, grill or sear, grease-laden vapour rises into the hood. Filters catch some of it, but not all. The rest travels into the duct, cools and sticks to the walls. Over weeks and months, that film turns into a thick, flammable layer that coats the entire run from the hood to the exhaust fan.
The problem is simple: grease in a duct is fuel in a chimney. If a flare-up on the line gets pulled into the hood, a dirty duct gives that fire a direct path through your building and up to the roof. A fire that might have stayed on the cooktop can suddenly become a structure fire.
Source: NFPA, Structure Fires in Eating and Drinking Establishments. Canadian kitchens use the same equipment and face the same risk.
5 Reasons Duct Cleaning Can’t Be Skipped
1. It Prevents Grease Fires From Spreading
Your fire suppression system protects the cooking line, but it can’t stop a fire that has already climbed into a grease-coated duct. Cleaning the ducts down to bare metal removes the fuel, which is the only real way to keep a kitchen fire contained.
2. It’s Required by Code
Fire codes across Canada, including Nova Scotia’s (which adopts the National Fire Code of Canada), require commercial cooking exhaust systems to be maintained to NFPA 96. That standard says the entire exhaust system, including the hood, ducts and fan, must be inspected on a set schedule and cleaned to bare metal when grease is found. A fire inspector can ask to see your cleaning records. (Here’s why you should check certifications before hiring a hood cleaner.)
3. It Protects Your Insurance Coverage
After a kitchen fire, one of the first things an insurer will ask for is proof your exhaust system was maintained. Missing or outdated service reports can complicate or delay a claim. A current certificate and a hood sticker with your last and next service date are your paper trail.
4. Your Kitchen Runs Better
Grease narrows ducts and weighs down fan blades. That means weaker airflow, a hotter and smokier kitchen, lingering odours, and a fan motor working harder than it should. Clean ducts move air the way the system was designed to.
5. It Saves Money on Repairs
Grease that drips out of a roof fan can damage roofing membranes, and heavy buildup wears out fan bearings and belts. Regular cleaning catches these problems early, before they turn into roof repairs or a fan replacement.
How Often Should Kitchen Exhaust Ducts Be Cleaned?
NFPA 96 sets inspection frequency based on how much and what kind of cooking you do. If an inspection finds grease buildup, the system must be cleaned.
| Type of Cooking | Inspection Frequency |
|---|---|
| Solid fuel (wood or charcoal) | Monthly |
| High volume (24-hour kitchens, charbroiling, wok cooking) | Quarterly |
| Moderate volume (most full-service restaurants) | Every 6 months |
| Low volume (churches, day camps, seasonal businesses, senior centres) | Annually |
These are minimums. A busy fryer-heavy kitchen may need cleaning more often than its category suggests.
Warning Signs Your Ducts Need Attention
- Grease dripping from the hood edges or filters
- Grease pooling or staining around the exhaust fan on the roof
- Smoke hanging in the kitchen instead of clearing quickly
- Louder or rattling exhaust fan
- Your hood sticker shows a past-due service date, or there’s no sticker at all
What Proper Kitchen Exhaust Duct Cleaning Includes
When our crew cleans a kitchen exhaust system, we:
- Protect your cooking line and equipment before we start
- Clean the hood canopy, plenum and filters
- Scrape and degrease the ductwork through access panels, down to bare metal
- Clean the rooftop exhaust fan, blades and housing
- Leave the kitchen clean and ready for service
- Provide before-and-after photos, a written service report and an updated hood certificate sticker
That documentation is what keeps you covered with your fire inspector and your insurer.
Frequently Asked Questions
Is kitchen duct cleaning the same as home air duct cleaning?
No. Home duct cleaning deals with dust in heating and cooling vents. Kitchen exhaust duct cleaning removes flammable grease from commercial cooking exhaust systems and must follow NFPA 96.
Can my staff clean the ducts themselves?
Staff can and should wash filters regularly, but NFPA 96 calls for the exhaust system to be cleaned by a properly trained, qualified and certified person. Ductwork and rooftop fans also involve working at heights and around electrical components.
How long does a hood and duct cleaning take?
Most single-hood restaurant systems take a few hours. We schedule overnight or before opening so your kitchen doesn’t lose service time.
Do you serve areas outside Halifax?
Yes. We’re based in Bedford and serve commercial kitchens across Nova Scotia and Atlantic Canada.
Is Your Kitchen Due for a Cleaning?
AA Cleaning Solutions provides NFPA 96 compliant hood and duct cleaning across Atlantic Canada, with full photo reports and certificates after every job. Send us a few photos of your hood and we’ll get you a quote.