Kitchen Extraction and Ventilation for Food Retail Construction

July 20, 2026

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Extraction and ventilation in food retail is not a finishing detail. It is a legal requirement that sits at the centre of the construction programme, affects the planning application, and determines whether building control will sign off the unit.
It is also one of the most common sources of delay and cost on food retail fit outs. Not because the work is technically difficult, but because it tends to be specified too late, coordinated poorly with other trades, and treated as something to sort out near the end rather than something that shapes the whole programme from the start.
This post covers what the regulations require, what the common problems are, and what to get right before work starts.

Why Extraction Is Not Optional

Every enclosed food preparation environment in the UK is legally required to have an effective extraction system. The legal basis comes from several pieces of legislation that apply simultaneously.
The Workplace (Health, Safety and Welfare) Regulations 1992 require employers to provide effective and suitable ventilation in every enclosed workplace. In a food retail kitchen or food preparation area, that means mechanical extraction. Natural ventilation is not sufficient where cooking or food preparation generates heat, fumes, or airborne contaminants.
Building Regulations Part F sets the minimum ventilation rates required in commercial kitchens, covering both the extraction of contaminated air and the supply of fresh make-up air. The June 2023 amendment updated the standards for England and Wales. Any food retail fit out requiring building regulations approval must comply.
The Health and Safety at Work Act 1974 places a general duty on employers to provide a safe working environment. For a food retail kitchen, inadequate ventilation is a workplace health risk, not just a compliance gap.
The Fire Safety Order 2005 adds a further layer. Commercial kitchen ductwork is a known fire risk because of grease accumulation. The fire safety requirements for duct construction, fire dampers, and access for cleaning are not separate from the extraction design. They are part of it.
These are not alternative frameworks. They all apply at the same time, and a system that meets one but not the others is not compliant.

The Technical Standards That Actually Govern the Design

The regulations above set the legal requirements. The technical standards that tell you how to meet them in practice are:
  1. DW/172, published by BESA, which provides the industry specification for kitchen ventilation systems. It covers canopy sizing, airflow rates, grease filtration, duct construction, and fire safety. Any ventilation design engineer working on a food retail project should be designing to DW/172.
  2. TR/19, also published by BESA, which covers the internal cleanliness of ventilation systems and sets out cleaning schedules for ductwork. A system that meets TR/19 requirements at installation can be demonstrated to be clean. A system that cannot be accessed for cleaning does not meet the standard regardless of what the initial specification says.
  3. BS 6173, which covers the installation and maintenance of gas-fired catering appliances, including the requirement for adequate ventilation and gas interlock systems.
The gas interlock requirement under BS 6173 catches people out. A gas interlock system monitors the ventilation and shuts off the gas supply to cooking equipment if the extraction is not running. It is a mandatory requirement where gas appliances are installed in a catering environment. It is not an optional upgrade.

Make-Up Air: The Part Most People Get Wrong

Extraction removes contaminated air from the kitchen. But air is a fluid. If you extract air without replacing it, you create negative pressure in the space. Negative pressure causes problems: doors become difficult to open, combustion appliances may not draw correctly, and in severe cases you can get back-draught through gas appliances.
Make-up air is the supply of fresh air to replace what is extracted. The design standard is to supply somewhere between 80 and 90 percent of the extracted volume as make-up air. The remaining 10 to 20 percent is made up through natural infiltration, which maintains a slight negative pressure in the kitchen relative to adjacent areas, preventing cooking odours from migrating into the retail sales space.
Make-up air is the element most often underspecified or omitted from early designs. A canopy and extraction fan are visible. A make-up air unit is not. Designs that specify extraction without properly accounting for make-up air result in a system that cannot maintain the required airflow, fails its commissioning test, and requires expensive remedial work to correct.
Make-up air supply also needs to be conditioned in most food retail applications. Delivering untempered outside air directly into a food preparation area in winter creates a cold, uncomfortable working environment and can affect food safety by introducing cold spots near open refrigeration. The make-up air design needs to account for this from the start, not after the unit is fitted out.

Odour Control and Planning

If your food retail unit prepares or cooks food on the premises, odour from the extraction discharge is likely to be a material planning consideration. This applies whether you are fitting out a new unit or changing the use of an existing one.
Local authorities assess odour impact on neighbouring properties and the surrounding environment. The standard used is the EMAQ+ guidance document, Control of Odour and Noise from Kitchen Exhaust Systems. Planning officers and environmental health teams use this to assess whether a proposed extraction system is adequate and whether the discharge point is acceptable.
The practical implications are:
  1. Where the extraction discharge is close to residential properties or sensitive receptors, activated carbon filtration or UV-C odour control is typically required. This is not a recommendation. It is what planning conditions and environmental health teams will require.
  2. The route of the extract duct and the location of the discharge point need to be agreed with the local authority before work starts, not after the duct has been installed.
  3. Noise from extraction fans is assessed separately. A fan that meets the airflow requirements but generates noise above the permitted level at the nearest sensitive receptor will not pass environmental health scrutiny.
Getting extraction discharge and odour control wrong at design stage is one of the most common reasons a food retail planning application or a building regulations application gets challenged after work has started. Fix the design before work begins. Changing the duct route or adding odour control after the ceiling is in costs significantly more than getting it right first time.

Fire Safety in Ductwork

Grease accumulates in kitchen extract ductwork. Grease is flammable. Kitchen fires that travel through ductwork are a known and serious risk in food retail environments, and the fire safety requirements for duct construction reflect that.
Kitchen extract ductwork must be constructed from steel with a minimum thickness specified in DW/172. It must be continuous, with no joints that allow grease to accumulate or fire to spread. It must have access panels at regular intervals, positioned so that the entire duct can be cleaned. And it must be separated from combustible materials by the required distances or by fire-resistant enclosures where it passes through other parts of the building.
Fire dampers are required where ductwork passes through compartment walls or floors. The dampers must be the correct type for the application and must be accessible for testing and maintenance.
TR/19 cleaning frequency requirements apply from the day the system is commissioned. A duct that has never been cleaned is a fire risk. Building control and the fire authority will want to see that the system has been designed for TR/19 compliance, meaning adequate access is built into the installation rather than retrofitted later when the first cleaning inspection reveals the ductwork cannot be accessed.

How Extraction Affects the Construction Programme

Extraction design affects the programme in ways that are not obvious until the job is underway. These are the most common impacts:
  1. Duct routes often conflict with structural elements, other services, or ceiling voids that were not coordinated at design stage. Discovering that the extract duct cannot follow the specified route once the ceiling grid is in costs time and money to resolve.
  2. Roof penetrations for the extract discharge require structural approval if they are in a load-bearing element, landlord approval if the building is not yours, and waterproofing details that are separate from the extraction specification. None of these are the extraction contractor's responsibility by default.
  3. Make-up air units are often large pieces of plant that need a structural support and a services connection. If the support is not in place when the unit arrives, the unit cannot be installed and the programme stalls.
  4. Gas interlock commissioning requires the extraction to be running before the gas engineer will sign off the appliances. If extraction commissioning slips, gas sign-off slips with it, and a food retail store cannot open without the gas appliances commissioned.
These are not unusual problems. They happen on food retail fit outs regularly. They are avoidable with proper coordination between the extraction designer, the M&E engineer, the structural engineer, and the principal contractor before work starts.

What to Confirm Before the Extraction Package Is Designed

  1. What cooking processes and equipment will the kitchen operate? The extraction design is based on the cooking load. A bakery counter with deck ovens has a different extraction requirement from a hot food counter with fryers. Designing to the wrong load produces either an undersized system that fails commissioning or an oversized system that costs more than necessary.
  2. Where can the extract duct route go, and where is the discharge point? This needs to be agreed with the building owner, the local authority, and the neighbouring properties before the design is fixed.
  3. Is planning permission or prior approval required for the extraction discharge? For a change of use or a new food preparation use in an existing building, this is almost always yes.
  4. Has the structural engineer confirmed the duct route through the building and the support for the make-up air unit and any roof-mounted plant?
  5. Is a gas interlock system required, and who is responsible for designing and commissioning it?

What to Ask Your Contractor

  1. Who is designing the extraction system, and are they designing to DW/172?
  2. Have you built food retail extraction systems with gas interlock before, and can you show us a project where the system passed commissioning first time?
  3. How is make-up air handled in this design, and has the supply volume been calculated against the extraction rate?
  4. What access provision is built into the ductwork installation for TR/19 cleaning?
  5. Who is coordinating the duct route with the structural engineer and the other M&E trades?
A contractor with genuine food retail experience answers all of these from projects they have actually delivered. One without it tends to treat extraction as a package to be handed to a specialist subcontractor without coordinating it with the rest of the programme.

The Honest Summary

Kitchen extraction and ventilation in food retail affects planning, building regulations, fire safety, gas safety, and workplace health and safety simultaneously. It is not a single trade package. It is a system that touches almost every other element of the fit out, and it needs to be coordinated from the start of the design process, not bolted on at the end.
The problems that cause the most delay and cost on food retail fit outs are almost always the result of extraction being specified too late, make-up air being underdesigned, or duct routes being agreed in principle but never properly coordinated with the structure and the other services.
We have delivered food retail construction across the UK, including eleven Lidl supermarkets, and extraction coordination is part of every food retail programme we run. If you are planning a food retail fit out and want to understand what the extraction requirements mean for your specific project and programme, get in touch with our team. We will work through it with you before the design is fixed.