Phoenix Journal · Ductwork
When homes sit directly above your extract system, ordinary kitchen maintenance becomes a shared safety matter. Here is what changes, and the duties that come with it.
A commercial kitchen is a demanding thing to run at the best of times. Put homes directly above it - a flat, a row of bedrooms, a whole block - and the ordinary duties of extract cleaning, odour control and fire safety stop being purely your own concern. They become a matter of other people's sleep, comfort and safety.
Mixed-use buildings are everywhere in UK high streets: a restaurant, cafe or takeaway on the ground floor with residential accommodation above or alongside. It is a sensible use of space, but it changes the risk picture. The same greasy duct that would be a nuisance in a standalone unit is, in this setting, a fire route running up through the fabric of people's homes. The same fan that hums quietly on an industrial estate is now a neighbour's night-time complaint. This page walks through what genuinely changes when you cook below residential flats, and the extra duties that come with it.
The physics of your kitchen do not change because someone lives upstairs, but the consequences do. Three things are amplified: fire, smell and sound. Each is governed by its own set of rules, and each is judged more harshly when a home is on the receiving end.
Fire is the headline. Grease-laden vapour condenses inside ductwork, and industry figures attribute a large share of commercial kitchen fires - commonly cited at around 70 percent - to a build-up of fat and grease in the extract system. When that deposit ignites, flames travel fast through the duct itself, and a duct in a mixed-use building runs directly through floors and voids shared with the flats above. A contained kitchen fire can become a building evacuation in minutes. That is why kitchens beneath homes are treated as a serious life-safety concern rather than a property matter alone.
Odour is the daily grievance. Cooking smells that would disperse harmlessly over a car park will drift straight into open bedroom windows when the discharge point is low or poorly placed. Local authorities lean on guidance derived from DEFRA's work and updated through the EMAQ+ programme, whose Annex C sets out a risk assessment for odour that scales the control required to the sensitivity of the surroundings. Homes directly above or beside you push you firmly into the higher-control end of that scale.
Noise and vibration complete the picture. A fan or a run of ductwork transmits low-frequency hum and structure-borne vibration into the rooms it passes. Part E of the Building Regulations already concerns the passage of sound between a commercial unit and attached dwellings, and it is routinely cited where kitchens and homes share a structure. Anti-vibration mountings on fans and duct fixings, and keeping fans inside the building where practical, are the standard expectations.
The numbers that shape the duty
These are the current UK reference points a planner, an environmental health officer or a fire risk assessor is likely to hold you to when homes sit above the kitchen.
Odour control sits alongside these. Where the risk assessment demands it, activated carbon filters are fitted internally after the grease filters, sized to give the adsorption contact time the guidance calls for - a minimum of around 0.2 seconds - and exchanged roughly every four to six months as they load up. None of this works if the grease filters and duct behind them are neglected, which is where cleaning and odour control become one continuous duty rather than two.
The anchor standard is TR19® Grease, published by BESA, which the fire service, environmental health and insurers all treat as the benchmark for what counts as adequate maintenance of a kitchen extract system. It sets measurable targets rather than vague promises: grease should be controlled so it does not exceed a mean average of 200 microns between scheduled cleans, deposits of 500 microns or more call for immediate spot cleaning, and a properly cleaned system should be brought down below roughly 50 microns - about half the thickness of a human hair. A post-clean report with pre and post readings and access-panel photographs is your evidence that the standard was met.
That evidence matters more when people live above you. Under the Regulatory Reform (Fire Safety) Order 2005, the responsible person for the premises must carry out and maintain a fire risk assessment, and a neglected, grease-choked duct running up past occupied flats is very hard to defend if it is ever questioned. Many insurers make TR19® adherence an explicit condition of cover, and a claim following a duct fire can be refused where the cleaning regime cannot be shown. In a mixed-use block that may also fall under wider building safety duties, a defensible paper trail is not a nicety - it is the thing that protects you when someone asks who was responsible.
There is a further point that is easy to overlook. Extract systems in mixed-use buildings do not only carry grease and smell; they sit within the ventilation strategy that keeps combustion products moving away from occupied space. Carbon dioxide (CO₂) and, more dangerously, carbon monoxide from gas cooking appliances must be carried clear, and a fouled or under-performing system undermines that. It is worth understanding the carbon monoxide risk in commercial kitchens as part of the same duty of care you owe the residents above you, because clean, well-drawing ductwork is what keeps those gases from lingering.
Put together, cooking below homes asks you to do the same jobs as any commercial kitchen, but to a tighter standard and with the paperwork to prove it: clean to TR19® on a frequency that matches your hours, control odour to the level the site's sensitivity demands, keep noise and vibration out of the fabric, and discharge high and fast enough to carry the plume away from windows. Done well, most residents never think about the kitchen beneath them - which is exactly the goal.
Questions
Cleaning frequency under TR19 Grease is set by how many hours a day you cook, not by the flats themselves. Heavy use of around 12 to 16 hours a day points to cleaning roughly every three months, moderate use every six months, and light use annually. When homes sit above the kitchen, err towards the shorter interval and keep documented pre and post reports, because the fire consequences of a grease build-up are far greater in a mixed-use building.
Guidance commonly asks for the discharge to terminate at least one metre above the eaves and any dormer window, so the plume rises clear of upstairs windows. The efflux velocity at the terminal is often required to be at least 12 m/s, which usually means fitting a venturi outlet to throw the plume high enough to disperse. Discharging low or slowly next to flats is a frequent reason for planning refusal and odour complaints.
Very likely, yes. The odour risk assessment scales the control required to how sensitive the surroundings are, and homes directly above push you towards higher control. That normally means activated carbon filters fitted internally after the grease filters, sized for adequate adsorption contact time and exchanged roughly every four to six months. Carbon only works if the grease filters and ductwork behind it are kept clean, so it sits alongside your cleaning regime, not instead of it.
Under the Regulatory Reform (Fire Safety) Order 2005 the responsible person must carry out and maintain a fire risk assessment covering the extract system. A neglected, grease-laden duct running past occupied flats is very difficult to defend, and many insurers make TR19 adherence a condition of cover, so a claim can be refused if cleaning cannot be evidenced. Keeping certified cleaning records with grease readings and photographs is the practical way to show you met the duty.
Phoenix Duct Clean · by the numbers
Phoenix surveys and cleans kitchen and building ductwork to the TR19 standard - measured, cleaned and certificated, UK-wide.