Commercial kitchen duct cleaning is more than wiping the visible hood. A proper service considers the entire exhaust path, including filters, the hood and plenum, duct runs, and the exhaust fan. If grease remains in hidden sections, surface cleaning may leave an important part of the system unaddressed.
This guide explains how to assess the need for cleaning, prepare your kitchen, understand the professional process, and verify the work afterward. It also separates routine operator checks from work that should be handled by trained commercial kitchen cleaning professionals.
Visible Hood Cleaning vs. Full Commercial Kitchen Duct Cleaning
Routine wiping can keep the exposed hood looking cleaner, but it does not necessarily remove grease from the ventilation path. Full kitchen exhaust cleaning addresses the components that carry grease-laden vapours away from the cooking line.
| Visible surface cleaning | Full exhaust-system cleaning |
|---|---|
| Focuses on exposed hood surfaces and readily accessible areas. | Considers the hood, filters, plenum, duct runs, and exhaust fan. |
| May support regular appearance and hygiene checks. | Addresses hidden grease accumulation and the condition of the complete exhaust path. |
| Can be part of routine kitchen upkeep within staff training and safety limits. | Requires planning, safe access, suitable containment, and professional handling of higher-risk areas. |
| Does not prove that internal ducts or rooftop equipment are clean. | Creates a clearer basis for service records, follow-up recommendations, and maintenance planning. |
Grease deposits inside a duct can contribute to a fire path beyond the visible hood. For a closer explanation of exhaust duct fire prevention, consider how grease accumulation, duct access, fan cleaning, and documentation fit together rather than treating the hood as an isolated appliance.
Step 1: Assess the Exhaust System and Warning Signs
Begin with an observation of the system, not an attempt to dismantle it. Look for grease streaks at hood seams, persistent cooking odors, smoke escaping or spilling from the hood, reduced airflow, quickly saturated filters, or a fan that has become noisy or vibrates during operation.
Also check for grease staining around the rooftop exhaust fan. These signs help identify where a professional should investigate, but they cannot confirm that a duct is clean. Internal buildup may remain even when the hood looks acceptable.
Step 2: Confirm the Cleaning Scope Before Work Begins
Before booking service, ask for the scope in writing. A useful scope should identify which of the following are included:
- Hood surfaces, seams, corners, and the plenum.
- Filters, including cleaning or exchange where appropriate.
- Duct runs and the access points used to inspect or clean them.
- The exhaust fan, fan housing, and surrounding rooftop area.
- Protection and containment for nearby equipment and surfaces.
- Service tags, before-and-after photographs, a report, and follow-up recommendations.
Ask whether fan-belt replacement, electrical repairs, access-panel work, roof repairs, or fire-suppression servicing are separate from cleaning. A cleaning provider should distinguish completed cleaning from repairs that require another trade or additional approval.
Step 3: Prepare the Kitchen and Protect People and Equipment
Schedule the work during a suitable shutdown or low-activity period. Coordinate with the kitchen manager so staff know which cooking equipment, work surfaces, storage areas, and access routes must be cleared before the crew arrives.
Preparation should also cover protection of food, utensils, appliances, floors, walls, and nearby surfaces. Confirm how the provider will manage access and cleanup, especially if the system includes a rooftop fan or difficult duct route.
Do not allow untrained staff to enter ducts, climb onto a roof, work around energized fan equipment, interfere with fire-suppression components, or handle commercial cleaning chemicals without appropriate training and controls. Operators can prepare the space and communicate system information. Higher-risk work belongs with trained professionals.
Step 4: Remove, Clean, or Exchange Filters
Filters help capture grease before it travels farther into the ventilation system. During service, they may be deep cleaned or exchanged depending on their condition and the agreed scope. Filters that are damaged, heavily saturated, missing, or incorrectly seated need attention because they can affect airflow and grease capture.
After filters are reinstalled, verify that they fit correctly, face the intended direction, and sit securely without obvious gaps. Do not invent a replacement interval based only on a calendar. Filter condition, cooking activity, and the provider’s recommendations should inform the maintenance plan.
Step 5: Degrease the Hood and Plenum
The hood and plenum can collect grease around seams, corners, edges, lights, and the transition into the duct. Professional cleaning should address those areas rather than stopping where the metal is easiest to see.
The work also needs to protect components that should not be exposed to unsuitable chemicals, moisture, or physical disturbance. Chemical use, commercial cleaning equipment, and work near fire-suppression components should be handled by trained personnel. The goal is not simply a better-looking hood. It is a cleaner, safer transition into the exhaust system.
Step 6: Access and Clean the Duct Runs
Duct cleaning requires a safe way to inspect and reach the internal surfaces. Access panels, where present, allow technicians to assess the duct route and address deposits beyond the hood. The exact approach depends on the system layout and the safe access available.
This is not a suitable do-it-yourself task for most restaurant staff. Grease ducts can involve confined or elevated areas, rooftop equipment, electrical hazards, and fire-protection requirements. Do not cut into a duct, remove an access panel, or use improvised tools to reach internal surfaces.
Ontario’s Fire Code requires cooking operations that produce smoke or grease-laden vapours to have an exhaust system and fire-protection system in accordance with NFPA 96. It also addresses fire separations enclosing grease ducts through related building-code requirements. You can verify the applicable wording in the Ontario Fire Code and Ontario Building Code regulation.
Step 7: Inspect and Clean the Exhaust Fan
The exhaust fan is the final major part of the path and should not be omitted from a duct-cleaning discussion. Grease on the fan or housing, unusual noise, vibration, reduced draw, or staining around the roof can indicate that the fan needs cleaning or further maintenance.
Cleaning and mechanical repair are different decisions. A provider may identify a worn fan belt or another maintenance concern, but belt replacement, electrical work, balancing, and equipment repairs should be clearly recorded as separate actions unless they are included in the agreed service.
Step 8: Record the Work and Keep Inspection-Ready Evidence
Ontario’s Fire Code requires hoods, ducts, and filters subject to combustible deposits to be checked at intervals not greater than seven days. They must be cleaned when the accumulation creates a fire hazard. This is a checking requirement, not a universal instruction to book a full deep cleaning every seven days.
Keep a file containing the service date, areas cleaned, access points addressed, service tags, before-and-after photographs, the service report, and any recommendations. A commercial kitchen safety inspection checklist can help operators track duct inspection points, current tags, filter condition, and follow-up items between professional visits.
Good records support responsible maintenance, but they do not guarantee inspection approval, insurance coverage, or regulatory compliance by themselves. The condition of the system and the requirements applicable to the operation still matter.
Step 9: Verify the Completed Cleaning
Before the crew leaves, compare the completed work with the agreed scope. Confirm that the hood, plenum, filters, duct access points, duct runs, and fan were either cleaned or specifically noted as outside the service.
- Filters are clean or exchanged, seated correctly, and free from obvious damage.
- Visible grease has been removed from hood surfaces, seams, and accessible areas.
- Duct access points and the areas reached through them are documented.
- The fan condition is recorded, including any noise, vibration, belt, or repair concern.
- Rooftop residue and runoff have been managed according to the agreed work plan.
- Service tags, photographs, reports, and follow-up recommendations are filed.
- Outstanding repairs are separated from the cleaning that was completed.
How to Plan Future Cleaning Without Using a One-Size-Fits-All Schedule
Maintenance planning should reflect the way the kitchen operates. Cooking volume, fuel type, fryer-heavy work, menu changes, and the speed at which combustible deposits return can all affect the appropriate service approach.
Use the required checks to notice changes early, then use observations and professional findings to plan deeper service. A kitchen with persistent smoke spillage, fast filter saturation, or heavy grease return may need attention sooner than a lighter-duty operation. Avoid treating a generic calendar interval as a substitute for checking the actual system.
Commercial Kitchen Duct Cleaning Booking Checklist
Before approving a service, ask these practical questions:
- Does the scope include the hood, filters, plenum, ducts, and exhaust fan?
- How will the provider reach and document duct access points?
- How will nearby equipment, food-contact surfaces, floors, and rooftop areas be protected?
- Which work is cleaning, and which work would be a separate repair or replacement?
- Will the service include photographs, service tags, and a written report?
- What warning signs or conditions should be monitored before the next visit?
- Can the service be scheduled during a period that avoids exposing staff and customers to the work area?
Frequently Asked Questions
Can restaurant staff clean commercial kitchen ducts themselves?
Staff can perform routine visual checks and maintain accessible surfaces within their training and workplace procedures. Duct access, rooftop fan work, electrical components, fire-suppression equipment, and higher-risk chemical or elevated work should be left to trained professionals.
What parts of a commercial kitchen exhaust system should duct cleaning include?
The scope should consider the hood, filters, plenum, duct runs, and exhaust fan. Ask the provider to identify any component not included so a visible hood cleaning is not mistaken for full-system service.
Does Ontario require commercial kitchen ducts to be checked every seven days?
Ontario’s Fire Code says that hoods, ducts, and filters subject to combustible deposits must be checked at intervals not greater than seven days. They must be cleaned when deposits create a fire hazard. This does not establish one universal deep-cleaning schedule for every kitchen.
What documentation should I request after commercial kitchen duct cleaning?
Request the service date, scope, areas addressed, service tags, before-and-after photographs, a written report, and any recommendations or excluded repairs. Keep these records with your kitchen safety documentation.
How do I know whether a commercial kitchen needs duct cleaning or only hood and filter cleaning?
Warning signs such as grease streaks, persistent odors, smoke spillage, reduced airflow, fan noise, vibration, or roof staining justify an assessment of the wider exhaust path. If ducts and the fan have not been inspected or documented, do not assume that hood and filter cleaning is enough.
Conclusion: Know When Surface Cleaning Is Not Enough
Commercial kitchen duct cleaning should be treated as an exhaust-system task, not a cosmetic hood service. Start with warning signs and the system’s history, confirm that the scope reaches the ducts and fan, prepare the kitchen safely, and retain records that show what was completed.
For Ontario restaurants and other food-service operations, regular checks help identify combustible buildup before it becomes a larger maintenance or safety concern. When hidden areas have not been addressed, airflow or grease problems persist, or inspection records are incomplete, arrange a professional assessment rather than relying on surface cleaning alone.
Robinhood Cleaners provides commercial kitchen exhaust cleaning, duct cleaning, filter cleaning and exchange, exhaust fan maintenance, and related kitchen cleaning services across Ontario.