What Is Included in a Commercial Kitchen Extract System?
Do not buy “a canopy clean” when the requirement concerns the extraction system.
A commercial kitchen extract system can extend from the cooking area through the canopy, filters, plenum, horizontal ductwork, vertical riser, fan and final discharge. If that route is not described before contractors quote, different suppliers can appear to be pricing the same job while actually including very different amounts of work.
The quotation should tell you which parts of the extraction route are included.
Terms such as “extract clean”, “duct clean”, “hood clean” and “TR19 clean” are often used loosely. Unless the contractor identifies the actual system, a facilities manager may not know whether the quoted price includes only the visible canopy or the full route through ductwork, fan and discharge.
BESA’s current January 2026 kitchen-extract guidance says TR19® Grease cleaning encompasses the entire ventilation system, including the canopy, fan and full length of the ductwork, and explains that grease can continue through filters and accumulate across the extraction route to atmosphere.
Define the system from the kitchen towards atmosphere.
1. Cooking line & canopy
Identify which canopy serves which cooking equipment. Larger kitchens may have several canopies or separate extract systems, so “the kitchen extract” may not describe one single asset.
2. Filters & plenum
Filter cleaning is important routine maintenance, but BESA’s current guidance makes clear that filters are not fully effective at stopping grease from entering the downstream system. The plenum and route beyond therefore remain relevant.
3. Horizontal duct runs
Ductwork may cross ceilings, corridors or service areas before reaching a riser or external wall. Record approximate route and known access points where information is available.
4. Vertical riser
A riser may pass through several floors or a landlord-controlled shaft. Long concealed sections can materially affect both cleaning access and quotation scope.
5. Extract fan
The fan can be roof-mounted, wall-mounted or located within plant space. Confirm whether access to it is included and whether roof or landlord arrangements are required.
6. Final discharge
The termination forms the downstream end of the extract route. The contractor’s scope should make clear whether the route through and around the final discharge is included where technically applicable.
TR19® Grease follows grease through the system—not just what can be seen from the kitchen.
BESA describes TR19® Grease as the definitive specification for managing fire risks associated with grease accumulation within commercial kitchen extraction systems.
Its January 2026 technical guidance says cleaning encompasses the complete extract system, including canopy, fan and the full ductwork route. It also says filter maintenance alone is insufficient because grease vapours can pass through or around filters and accumulate on downstream internal surfaces, fans and discharge points.
This is why system definition matters before procurement. The scope should follow the actual extraction route rather than using a service label as a substitute for knowing the asset.
The contractor still needs to know which canopy, duct route, riser, fan and discharge form the system being priced.
Cleaning specification and ventilation-system specification are related—but they are not the same document.
BESA describes DW/172 as its definitive industry standard for designing, installing and maintaining commercial kitchen ventilation systems. The current publication is the second edition from 2018, with a May 2024 addendum covering updated guidance on fire-resisting and smoke-control ductwork.
TR19® Grease is focused specifically on management of grease accumulation and associated fire risk through inspection and cleaning. DW/172 addresses the wider kitchen-ventilation system itself, including design and installation considerations.
For the specifier, the practical point is to avoid using “TR19” as if it were a complete design description of the ventilation installation. Where the problem concerns design, system alteration, airflow, fire-resisting ductwork or other engineering matters, appropriate building-services design expertise may be required in addition to grease-hygiene work.
Included in scope does not automatically mean accessible on the night.
A quotation may say that the full system is included, yet the contractor can only complete that scope if suitable access exists. BESA’s current guidance says comprehensive access throughout the duct system is necessary for effective inspection and cleaning and refers to access panels at regular intervals, typically around two to three metres where practicable.
System scope and access status should therefore be recorded separately. A duct section can be included in the intended scope but still remain inaccessible because of missing panels, a locked roof, high-level restrictions, landlord control or another building constraint.
The visible kitchen can hide a much longer extraction route.
The historic EC Cleaners archive includes both kitchen-facing equipment and downstream duct/fan components. These images illustrate why a commercial scope should connect the front end of the system with the route that continues through the building.
They are historic project context only and are not current Search and Submit Ltd system surveys or technical drawings.
A lower price may describe a smaller system.
Before comparing contractor totals, line up what each supplier has included. One quotation may price the canopy and accessible horizontal duct; another may include the riser, roof fan, discharge and additional access arrangements.
The purpose is not to force every contractor to use identical terminology. It is to make scope differences visible before appointment rather than discovering them after the work has been completed.
Compare the route, access assumptions, testing, reporting and exclusions before comparing the final number.
One kitchen does not always mean one extract system.
Large hospitality kitchens, hotels, universities, hospitals, food courts and production sites can contain several canopies and independent extract routes. An asset schedule should therefore avoid a single generic entry such as “main kitchen extract” if it actually covers several systems.
Separate identifiers make procurement, reporting and future maintenance clearer. They also reduce the risk that evidence for one extract route is assumed to cover another.
Use the best information available—then let the competent contractor verify the reality.
Existing drawings, previous reports, labelled photographs and maintenance records can make an initial enquiry significantly more accurate. They should not be treated as guaranteed current if the building has changed or the system has never been fully surveyed.
Where the route is genuinely unknown, a survey or verification stage may be commercially better than asking suppliers to submit a blind fixed price. The contractor can then identify the actual system, access limitations and any information needed before a full cleaning scope is agreed.
The post-clean report should answer the same system question as the original quotation.
At completion, the client should be able to compare the intended scope with what the contractor says was actually completed. BESA’s current guidance says post-clean verification reporting should include the work completed, photographs, relevant test results and access limitations or areas requiring attention.
If a section that was intended to be included could not be reached, the report should make that limitation explicit. The organisation can then move the issue into an access or remedial action rather than assuming the whole system is closed.
EC can make the commercial scope clearer without pretending to survey the system.
EC Cleaners Network can organise customer-supplied reports, drawings, photographs and previous quotations; identify which components and system sections are already described; highlight obvious scope gaps; and structure a clearer enquiry for independent specialist contractors.
EC does not inspect the duct route, determine the technical extent of contamination, design kitchen ventilation, verify airflow, decide fire-resisting ductwork requirements or determine which physical solution is technically correct. Those responsibilities remain with the appropriately competent contractor, engineer or designer.
Send the latest report, quotation, photographs or drawing.
EC can help organise the supplied information into a clearer commercial description of the extraction route, highlight what remains unknown and identify what contractors should clarify before competing quotations are compared.
EC Cleaners Network is operated by Search and Submit Ltd. This guidance provides general commercial and procurement information only and is not kitchen-ventilation design, fire engineering, mechanical engineering, legal or technical advice. Search and Submit Ltd does not inspect systems, verify duct routes, calculate airflow, design ventilation, determine fire-resisting ductwork requirements, determine TR19 compliance or certify contractor work. Independent appointed contractors, building-services engineers, designers and other competent professionals remain responsible for technical survey, design, assessment, physical work, reporting and certification within their own scope.