Phoenix Journal · Ductwork
Building Regulations Part F is the legal baseline for ventilation, but it stops well short of telling you how to size a kitchen canopy. Here is how Part F and the specialist standards fit together on a commercial extract system.
Regulations explained
If you run or fit out a commercial kitchen, Building Regulations Part F is the law you have to satisfy - but it is not the document that tells you how big your canopy or your extract fan needs to be.
That gap trips people up constantly. Part F of Schedule 1 to the Building Regulations sets a functional requirement: there must be adequate means of ventilation for the people in the building. The supporting guidance, Approved Document F, was updated to its 2021 edition and came into force in England on 15 June 2022. Volume 2 covers buildings other than dwellings, which is where your kitchen sits. It confirms that extract ventilation must be provided from kitchens to limit the spread of heat, moisture, grease and combustion products to the rest of the building - and then it points you at the specialist standards to actually do the design.
So the honest picture is that you are working to two things at once - the regulation that makes it a legal duty, and the industry specifications that make it a workable, cleanable, safe system. Below we set out what each one gives you, and where each one leaves you short, so you can see why a compliant kitchen leans on both.
Part F is the statutory hook. When building control signs off a new fit-out or a material change of use, this is the requirement they are checking your ventilation against, alongside Part B for fire and Part L for energy. Approved Document F Volume 2 is deliberately high-level for kitchens: it states the outcome you must achieve and cross-refers to CIBSE Guide B2, HSE Catering Information Sheet No. 10 (CAIS10), BESA TR/40 for local exhaust ventilation and HSG 258 for controlling airborne contaminants.
These are the specialist kitchen standards Part F effectively hands you off to. DW/172, the BESA Specification for Kitchen Ventilation Systems, is the recognised UK design and installation benchmark for catering extract. Alongside it sits the European series BS EN 16282, where Part 1 sets out the general requirements and the airflow calculation method, and Part 5 covers the design and dimensioning of the ductwork itself. Together they turn the Part F outcome into real numbers and real hardware.
In practice you do not choose between them - you use them as a pair. Part F is the reason the ventilation has to exist and perform; DW/172 and BS EN 16282 are how you prove it does. CIBSE Guide B backs this up with a minimum of around 30 air changes per hour for a busy commercial kitchen, which is far higher than anything in the general Part F tables and shows why the specialist route is unavoidable for catering. A design that quotes Part F but ignores the specifications will usually be under-extracted, hard to clean and awkward around gas safety.
The order that works is straightforward: establish the legal requirement through Part F, design the system to DW/172 and BS EN 16282, install it to those specifications, and then keep it clean to BESA TR/19 Grease so it carries on meeting all of them. That last step is where an operator stays compliant year after year - a beautifully designed system that silts up with grease is neither safe nor performing to the numbers it was built for.
Older buildings deserve particular care, because the ideal duct routes and make-up air paths often are not there. A structured survey is the way to close the gap between what the standards assume and what the fabric will allow - our note on how to spec a ventilation survey for an older building walks through what to capture before any design is finalised.
Questions
Not on its own. Part F sets the legal requirement that adequate extract ventilation must exist, but it does not give the canopy sizing, capture velocities or airflow volumes a catering line needs. You satisfy Part F by designing to the specialist standards - DW/172 and BS EN 16282 - and by keeping the system clean. Compliance is really the combination of the regulation and those specifications working together.
Part F of the Building Regulations is statute - it makes adequate ventilation a legal duty and is what building control check against. DW/172, the BESA Specification for Kitchen Ventilation Systems, is the industry design and installation benchmark that tells you how to actually achieve it. Approved Document F even points you towards specialist guidance rather than setting out kitchen extract rates itself, so the two are meant to be used as a pair.
DW/172 recommends replacement, or make-up, air of roughly 85 to 90% of the extract volume. Supplying less than that leaves the kitchen under negative pressure, which starves the canopy, makes doors hard to open and can pull in unfiltered air from elsewhere in the building. Getting the balance right is part of designing the system to the specialist standards, not just to Part F.
Phoenix Duct Clean · by the numbers
Phoenix surveys and cleans kitchen and building ductwork to the TR19 standard - measured, cleaned and certificated, UK-wide.