The air that leaves must be replaced: the importance of make-up air in a commercial kitchen
In a commercial kitchen, the extraction hood attracts much of the attention when ventilation is discussed: its dimensions, its position above the appliances and its ability to capture fumes and vapour are familiar considerations when planning an installation. Less visible, although equally necessary, is the supply of air needed to replace what is extracted—a part of the design that influences both overall system performance and working conditions during service.
Every volume of air discharged outside needs to be replaced. When this replacement has not been properly planned, air finds its way in through doors, windows or openings into adjoining rooms, following routes that do not always support effective capture or provide comfortable conditions for those working beside the cooking suite.
A balance to establish at the design stage
Extraction and make-up air need to be assessed together. Coordinating them requires consideration of how much air the kitchen needs, where it should enter and how it should be distributed in relation to the appliances, the hood position and the workstations.
A draught crossing the cooking area can divert fumes before they reach the hood, while a concentrated air supply directed at a workstation can cause discomfort for much of the working day. The location of supply points and the conditions under which air is delivered therefore deserve as much attention as the planned extraction route.
When replacement air is insufficient, signs may include doors that are difficult to open or strong air currents entering from adjacent spaces. These symptoms should be investigated in the context of the installation, particularly when accompanied by poor capture or uncomfortable draughts.
Why an open window does not necessarily provide adequate make-up air
In some kitchens, opening a door or window becomes the usual response when the atmosphere grows heavy during service. Although the opening allows air in, its effect depends on the wind, the outdoor temperature and conditions elsewhere on the premises, so it cannot be assumed to provide a sufficient, well-distributed supply.
This variability helps explain why an installation may behave differently from one day to the next, even when the cooking appliances are operating at a similar pace. Assessing the air supply makes it possible to reduce dependence on these circumstances and develop a solution suited to the kitchen’s intended use.
Before increasing extraction
When a hood is not capturing effectively, increasing the airflow may seem the most immediate response. Before making that change, however, it is worth reviewing the condition of the filters, the characteristics of the ductwork, the operation of the fan and the way replacement air enters the kitchen.
Extracting a greater volume of air also means replacing it, so any adjustment needs to be assessed in relation to the system as a whole. This review is particularly relevant when new appliances are introduced, the cooking suite is rearranged or ventilation conditions within the premises change.
At Luis Capdevila, we assess the needs of each kitchen to design bespoke ventilation and filtration solutions. If you are planning a new installation or looking to improve an existing one, we can help you consider extraction and make-up air together, taking into account how the kitchen operates every day.
