Air flow is really important for your restaurant kitchen
If you’re setting up a restaurant kitchen for the first time, or even renovating an existing kitchen, you probably don’t have to do much research to choose your kitchen’s cooking appliances. After all, food is your thing. Changes are you have known exactly what you want for a long time. But what about your commercial kitchen exhaust hood?
Air flow is probably not your thing. And when you start to research your options, you quickly discover that there’s a lot more to it than you thought. So here’s a quick primer that can help you choose the commercial kitchen exhaust hood that’s perfect for your food service establishment.
The right commercial kitchen exhaust hood is critical
Although it may not be as much fun as choosing the cooking appliances, your commercial kitchen exhaust hood must be carefully matched to the operation of your kitchen. Here’s why:
If you are using any cooking appliances that produce smoke and grease, to meet building codes you must choose a commercial kitchen exhaust hood with a fire suppression system.
Smoke, heat & grease removal
Besides meeting building codes, you must remove smoke for the health and safety of your kitchen staff. You also want them to be able to see what they are doing! And don’t forget, if smoke is not removed from the kitchen, it will eventually migrate to your dining room and drive away customers.
Heat removal is also critical to the functioning of your kitchen and your staff. The last thing you need is workers passing out because the kitchen is unbearably hot.
Removing grease is important for fire prevention, and also for cleanliness. Grease that’s not removed by your commercial kitchen exhaust hood will settle on your kitchen surfaces. That means your staff must spend more time cleaning.
Another important function of your commercial kitchen exhaust hood is keeping cooking odors from spreading throughout your restaurant. While your customers might love your onion soup, they don’t want to smell the onions cooking.
5 tips for choosing the right commercial kitchen exhaust hood
1. TYPE 1 OR TYPE 2?
You might have seen these designations when shopping for commercial kitchen exhaust hoods. What’s the difference and which one do you need? It depends on the type of cooking that you’re doing.
A Type 1 exhaust hood is designed to be liquid-tight, and includes a fire prevention system. So if you are doing any cooking that produces smoke and grease, such as frying, broiling or grilling, you need a Type 1 hood. If you are baking or steaming, which produce only heat and moisture, a Type 2 hood will typically be sufficient.
2. EXHAUST RATE
The amount of exhaust air removed from your space is expressed as cubic feet per minute, or CFM. The exhaust rate you need for your commercial kitchen exhaust hood depends on the heat, smoke and grease produced by the cooking appliances you’re using, as well as the type of foods you are working with.
For example, fatty foods produce more grease. Open-flame cooking produces more “thermal plume” than cooking on a griddle. All these factors need to be considered to calculate the exhaust rate you need for your commercial kitchen exhaust hood.
We recommend consulting with ventilation experts to get a recommendation about the exhaust rate your kitchen requires.
3. HOOD DESIGN
These are the basic commercial kitchen exhaust hood styles and their relative performance. The right choice for you will depend on the design of your kitchen the cooking appliances you’re using.
- Proximity hoods are smaller hoods mounted in closer proximity to the cooking appliance. Styles can include eyebrow, pass over or back-shelf hoods. In many cases, these styles require the least amount of exhaust to be effective and are great for lower exhaust rate applications.
- Wall-mounted canopy hoods, as the name implies, are mounted on the wall and typically extend over an entire bank of cooking appliances installed against the wall. Wall-mounted canopies are typically larger and require more exhaust volume than proximity designs.
- Island canopy hoods hang from the ceiling and are used over a bank of appliances in an island configuration. Island hoods typically require the most exhaust volume.
4. PHYSICAL SIZE and MOUNTING HEIGHT
Once you know the type, exhaust rate and design style you need for your kitchen, you also must consider the physical size of the commercial kitchen exhaust hood. Is it the right size to create the capture zone you need for your cooking appliances?
In most cases, the hood should extend beyond the area where your appliances are installed in order to keep grease and smoke from escaping into the surrounding areas. It’s also important that the hood be installed at the correct height. Once again these decisions will be based on your cooking appliances and the foods you are preparing.
This is another reason to consult with experts before purchasing your commercial kitchen exhaust hood.
5. VENTILATION DESIGN
This may be the most important tip of all:
Your ventilation design is just as important as the hood itself.
The size and shape of your ducting to the outside, the length of your ducting runs as well as the number and direction of bends that are needed, all have a huge impact on the effectiveness of your commercial kitchen exhaust hood. Longer runs and more bends may require a higher exhaust rate (more CFM).
Insulation is also needed when you are installing a Type 1 hood with fire suppression system. For ease of maintenance later on, you’ll also want access doors in your ductwork.
Makeup air is also an important factor in your ventilation design. Think about it: your commercial kitchen exhaust hood is removing a huge volume of air from your kitchen every minute to get rid of all that heat, odors, grease and smoke. Your ventilation must replace the air removed with fresh air from outside. That’s where the makeup air system comes in. Without it (or if it’s poorly designed), you risk air balance problems that can cause drafts and odors to migrate where you don’t want them.
For these reasons and many more, designing ventilation for a restaurant (particularly in the kitchen) requires specific knowledge and expertise. Make sure to choose an HVAC installation and service company with proven restaurant experience.