MEP Implications for Ghost & Dark Kitchens

Have you ordered food from a ghost kitchen? If you use delivery applications like Door Dash, Grubhub, or Uber Eats, odds are you have, whether you know or not.

Across the country, dark/ghost kitchens are popping up at warp speed. According to The Local Culinary, these facilities already sold an estimated $40 billion in food, with Euromonitor predicting $1 trillion in annual food sales by the end of 2030.

Meanwhile, these commercial kitchens may only cost owners a modest $150,000 or less to open for deliveries. In comparison, a McDonalds’ franchise restaurant costs, at a minimum, more than $1 million to open its doors according to Newswire.

In spaces that usually wouldn’t be conducive to restaurant space, commercial kitchens are being installed in affordable real estate locations, allowing owners to save their dollars in a busy property market. Storage facilities, former banks, and even previous retail spaces are being converted into commercial kitchens, only without the dining room to complement the fixture.

Granted, these kitchens aren’t without their own complications. Unlike McDonald’s, for example, these facilities typically don’t come with restaurant-ready equipment.

Given that reality, it’s important for ghost kitchen operators to confront the challenges in their utilities in an aggressive manner. However, the need for utility upgrades might not be so obvious to the untrained eye.

HVAC Considerations are Key for These Facilities

In all restaurants, a key aspect of safety and sanitation is the ventilation system. Look in any kitchen in America, from fast food to fine dining, and there’s necessity for fume hoods. Typically these unconventional spaces are often retrofitted from retail or storage space, so ventilation needs from prior tenants are completely different in almost all cases. Therefore, ghost kitchens should strongly consider making a significant investment into this aspect of their facility.

"With an increase in output from a kitchen beyond what it was designed for, it is essential that the life safety and exhaust systems are functioning properly. Fire suppression under the hood is the most important to provide chemical fire suppression precisely where fires are most likely to occur," said Tec Inc. mechanical engineer, Mike Ferrante.

"Hood exhaust and make-up air should be balanced properly to verify that the kitchen area is well ventilated. Every dish prepared in every kitchen has a chance of creating a dangerous situation. Proper ventilation and fire suppression minimize the inherent risk."

Investing in a high-efficiency exhaust hood from the get-go allows for an easier path to putting the rest of the ventilation system into motion. However, issues arise when compensating for the smaller space size. Whereas most kitchens design their exhaust hood to accommodate for heat load, it’s recommended that ghost kitchens take a two-pronged approach.

In Halton’s research on kitchen ventilation, they’ve found that these spaces can be optimized by considering their cooking equipment lineup, in addition to the length and design of the fan to fit in the spaces surrounding their heavy-duty equipment.

"Most kitchens require two HVAC systems, one for thermal comfort and another for fume hood or makeup air," said senior mechanical engineer Greshaud Allen, PE, LEED AP. "Special consideration has to be taken into account on the route of the exhaust ductwork and clearances to combustible building components. Exhaust outlets are another key component because of their clearance requirements."

"One energy efficiency strategy we have used in the past involved using heat sensors in the fume hood to modulate the exhaust and makeup air with a variable frequency drive (VFD). This demand control ventilation can reduce the energy consumption of this equipment by 50% during non-peak periods. "

While this may cause some to undergo a trial-and-error process until finding their solution, it’s seen as the best bet for long-term efficiency. However, working with an experienced consultant to find a solution cuts down the error

Ghost & Dark Kitchens Need to Factor in the Plumbing Problem

As restaurant owners know, grease is a significant factor, and compensating for it is essential to any kitchen. In most of the spaces where ghost and dark kitchens land, aspects of commercial kitchen plumbing weren’t considered in the initial facility’s design.

"One of the issues we have to deal with in any kitchen design is determining a location for a grease interceptor. This can prove to be difficult if the kitchen is placed on a ground level, with no basement," Mr. Allen said.

"Some local codes do not allow for these interceptors to be placed in the kitchen which adds to the complication as well as providing the necessary access for servicing.

This requires some investment from the owner to install components like grease traps and consider their needs for on-site oil storage. Obviously, storing excessive used oil on site is not only dangerous but is certainly also a sanitary concern.

Existing kitchens with flat tops and deep fryers may have multiple pieces of identical or similar equipment to eliminate flavor contamination or to improve the workflow of the kitchen. An issue I could see occurring would be a restaurant adding gas-fired equipment in order to operate as a ghost kitchen without modifying the natural gas, ventilation, and fire suppression systems. This could create a dangerous situation if existing systems are pushed beyond their limits," Mr. Ferrante explained.

"Alternatively, creating a commercial kitchen from an existing non-kitchen space in an existing building is always a difficult project no matter how small it appears. Locating a properly sized grease interceptor comes to mind as a challenge that always comes up when creating a commercial kitchen in an existing building."

In a recent article, DarPro Solutions recommended centralizing oil storage. This allows multiple fryers to all send run-off into a single space, which makes removal that much easier for an outside laborer.

Meanwhile, finding the right grease trap solution is something that should be addressed early in the process of opening these spaces.

As noted in an article from The Food Corridor, new owners of these spaces are frequently finding themselves discouraged when their exciting new investment comes without a proper grease trap for their space.

It’s recommended that facility owners make this investment early. Otherwise, they’ll find themselves having to clean out a 1,000-gallon grease trap all by themselves, hampering their ability to conduct business.

Avoid Issues in a New Ghost/Dark Kitchen Space, Engage An Engineer Early

With more investors joining this affordable and booming market in the coming years, it’s important for those entering the ghost and dark kitchen community to get their utilities in order.

"Engineers are able to identify each kitchen’s heating, cooling, and moisture loads and size equipment accordingly. There is no rule-of-thumb when it comes to kitchen design so each space has to be evaluated individually," Mr. Allen said.

"We'll provide clients with options like demand control ventilation to reduce operating costs."

Regardless of the needs of a given space, an engineering assessment is a great way to save money and hassle for ghost and dark kitchen owners. By finding issues early and recommending solutions for these spaces, operators can receive peace of mind through an engineer’s evaluation.

Engineers in the MEP field bring knowledge of commercial kitchens into play, plus keep affordability at the top of mind on their projects.

Want to avoid issues and keep a ghost kitchen in top shape? Bring in an expert early and save yourself from headaches down the road.

Mike Ferrante, Mechanical Engineer contributed to this article. Mike works with multi-disciplined design teams providing HVAC and plumbing design and coordination. He prides himself on proactive design solutions for complex renovation and fit-out projects.

Greshaud Allen, PE, LEED AP leads our Pittsburgh office and provides mechanical engineering and project management for all project types including higher education, commercial and residential projects. Greshaud is actively growing our presence in Pittsburgh and is very happy to be playing softball this summer with a league of AEC colleagues.