Phoenix Journal · Extraction
A new commercial kitchen is your one chance to build efficiency in from the start. Here is where the real savings sit - in the extraction, controls and heat recovery you specify before anything is installed.
A new kitchen is the one moment you get to design efficiency in from the start, rather than paying to bolt it on later - and the ventilation system is where the biggest savings hide.
Extraction is almost always the largest single electrical load in a commercial kitchen, and the make-up air it pulls in has to be heated through the winter. Get the design right and you cut running costs for the life of the building. Get it wrong and you are stuck oversizing, over-running and over-spending on every service visit that follows. This guide walks through the decisions that matter most while the drawings are still on the table.
Design decisions
Three areas do most of the work. Size the system honestly, control it intelligently, and recover the heat you have already paid for.
Getting it right
The ventilation strategy sets the tone, but an efficient kitchen is a set of joined-up decisions. The regulations frame most of them. Approved Document F of the Building Regulations covers ventilation in non-domestic buildings and sets the fresh-air baseline, while Approved Document L governs the conservation of fuel and power and pushes you toward efficient fans, controls and heat recovery. Underneath both sits the Workplace (Health, Safety and Welfare) Regulations 1992, which require effective and suitable ventilation in every enclosed workplace. DW172 is not law, but Environmental Health Officers, insurers and consultants treat it as the benchmark, so designing to it from day one saves awkward conversations later.
Appliance choice feeds straight back into the ventilation load. Every kilowatt of gas or electricity that ends up as radiant heat in the room is a kilowatt your extract and any comfort cooling then have to shift. Induction hobs put heat into the pan rather than the air, so a move away from open gas can shrink both the thermal convection coefficient DW172 applies and the airflow you need to design around. Well-insulated combi ovens, holding cabinets and fryers with tight lids do the same quieter job of keeping heat where it belongs. Specifying efficient equipment is not only about the appliance nameplate - it is about the ventilation, cooling and make-up air you avoid having to buy.
Water deserves the same scrutiny as air. Warewashing is one of the largest energy and water demands in the building because most of that water is heated, so the dishwash and glasswash layout you draw now decides years of consumption. Choosing efficient machines and planning the wash areas well is a design-stage decision worth taking seriously, and our guide to water efficiency in the pot wash and glass wash covers what to specify. It is also worth designing for the season you feel most: kitchens run hardest in summer, when tempering and cooling loads climb, and understanding why your energy bill runs higher in summer helps you size comfort cooling and heat recovery for the peaks rather than the average.
Finally, design for the clean. Efficiency you can measure on the drawing only survives if the system stays in good order. Fans, filters and ductwork clog with grease, and a fouled system draws more power, loses capture and drifts away from its design airflow within months. Build in generous access panels along the duct runs, hinged or slide-out filters, and easy reach to fan housings, so cleaning is quick, thorough and verifiable against DW172. A kitchen that is easy to clean is a kitchen that keeps performing at the efficiency you paid for - and one that passes the grease-hygiene inspections your insurer will ask about.
Questions
For most kitchens it is demand control kitchen ventilation (DCKV) paired with EC or inverter-driven fans. Because fan power rises with the cube of speed, letting the system slow down when cooking is light typically trims ventilation-related energy by 30 to 50 per cent. It also reduces the load on your heated make-up air by around 20 per cent, so the saving compounds across both electricity and heating.
DW172 is the BESA specification for kitchen ventilation systems, not a statute, but it is the recognised industry benchmark. Environmental Health Officers, insurers and design consultants use it to judge whether a system is fit for purpose. Designing to it from the start keeps you aligned with Building Regulations Approved Documents F and L and avoids costly redesign or insurance disputes later.
Every litre of air you extract has to be replaced. If that make-up air is dragged in through doors and gaps, it starves the extract, chills the space and pushes staff to add portable heaters. A dedicated air handling unit with heat recovery pre-warms incoming air using heat from the exhaust, and tempering it in winter means you reach a comfortable supply temperature for far less energy.
DW172 assigns each appliance a thermal convection coefficient based on its surface temperature and whether it runs on gas or electric, and that feeds directly into the airflow you must design around. Induction and well-insulated electric equipment put heat into the food rather than the room, lowering the extract volume and any comfort cooling you need. Choosing efficient appliances therefore shrinks the ventilation system you have to buy and run.
Phoenix Duct Clean · by the numbers
The right kit only helps if the system stays clean. Phoenix degreases canopies, filters and ductwork to TR19 Grease - UK-wide, overnight.