Great Facility Design Is More Than Just a Pretty Face

By Anthony Spata, Guest Author -- Foodservice Equipment & Supplies, 4/1/2006

Anthony J. Spata, PE Director of Architectural and Engineering Services WD Partners Columbus, Ohio

Rave restaurant reviews typically are credited to qualities such as having a creative, well-prepared menu, exemplary service or outstanding ambiance. While there’s no doubt such attributes are very important to the guest experience, as an engineer, I look at things differently. Sure it looks good, but how well does it work?

Good foodservice design transforms the visions of restaurateurs and designers into reality. Serving as the bedrock is a set of construction documents that: remain true to the concept, can be constructed within the budget, and be maintained and/or modified over the succeeding years with minimum effort.

Constantly wet floors, greasy walls and a hot and humid environment in a restaurant’s kitchen are symptoms of improper facility design. Incurring significant expense to relocate electric outlets, gas lines and water connections to accommodate a menu change should not be thought of as a cost of doing business. We can avoid the above by giving the same kind of attention to a restaurant’s mechanical, electrical and plumbing systems as to selection of tableware and chair-cushion fabrics.

HVAC
Usually, the kitchen designer selects exhaust hoods for the kitchen equipment, and the mechanical engineer is responsible for the design of the required ductwork and fans to serve them. In addition, the mechanical engineer must design HVAC systems that serve the very different requirements of the kitchen and dining areas. Integrating the kitchen’s exhaust and HVAC systems requires a thorough understanding of what cooking appliances will be part of the equipment package, their intended use and even the type of food they will prepare. In the dining area, the goal is the creation of an unobtrusive, quiet and draft-free system that provides precise temperature control.

Research conducted by the American Society of Heating, Cooling and Air-Conditioning Engineers (ASHRAE) has determined that the types, placements and locations of the appliances served by a hood have a profound impact on the quantity of air that must be exhausted for it to remove completely all smoke, heat and odor generated by cooking processes. It is imperative that the kitchen designer and mechanical engineer maintain communication to account for any appliance changes. In addition, the mechanical engineer should design the kitchen exhaust system to allow for flexibility in operation, changes in chefs, and menus that result in different appliance requirements.

The HVAC system serving the kitchen must meet or exceed those standards used for the HVAC design serving the dining area. As in the dining area, objectionable drafts need to be avoided because of their impact on occupant comfort. In addition, kitchen drafts adversely impact the performance of exhaust hoods, and can cause rapid, undesirable cooling of prepared foods. Conditioned air must be introduced at a low velocity, with supply points located away from all exhaust hoods. An additional challenge is avoiding conflicts between HVAC diffusers located in the ceiling and light fixtures, and supports for order monitors, speakers, fire protection (sprinkler) heads, etc.

Should your facility be one of the increasingly fewer restaurants that still permits smoking in a portion of the dining area, you face another significant challenge. The project’s mechanical engineer must perform an extensive airflow analysis to ensure no transfer occurs to the non-smoking portions. Not only must the air quantities associated with all ventilation systems be accounted for during planning, but the installation and operation must strictly follow the intended design.

Utility Distribution to Appliances
The traditional way of providing power (electric or gas) and water to kitchen appliances is a “dedicated connection” design, with a specific outlet or connection provided and located per the specified equipment requirements. Menu changes and equipment substitutions, or replacement, can result in the need to modify a receptacle to a different location, or change its voltage and/or amperage. Use of a “wireway,” which is a continuous, rectangular enclosure that contains electrical wiring and allows easy repositioning/changing of receptacles located behind the cookline, may make sense for new concepts where the menu and appliances are not finalized. Wireway mounting of receptacles is especially helpful when multiple equipment manufacturers are specified as acceptable for individual appliances. Variations in the locations of electric connections are easily accommodated by the ability to reposition receptacle locations.

Similarly, variations in water and gas requirements may be met by providing piping “manifolds” behind cooking equipment. Consisting of continuous, horizontal piping runs, the manifolds are surface-mounted on the rear wall behind the appliances, from six inches to 18 inches above the floor to avoid interference with the appliances. The individual manifolds for water and fuel should be uniformly sized along their entire length. This permits a connection, or tap, to occur wherever needed.

To accommodate the removal of water from items that require an indirect connection to a drain, a continuous “trench drain” may be used. Sinks should always be provided with a separate drain connection. Similar to an electric wireway and water/gas manifolds, a trench drain provides a continuous means to serve multiple equipment items. In instances where several individual floor drains would otherwise be required, trench drains incur little additional costs, allow flexibility for future equipment changes and eliminate plumbing costs related to adding/modifying drains.

Location of Electric Panels
The designated location of electric panels should consist of more than just finding wall space for them. Consider accessibility to facilitate turning circuits off/on, and flexibility for adding/modifying circuits as equipment requirements change.

Placing all electric panels in a back room, far away from the equipment and lights to which they provide power, increases the length of wires and conduits to these items, which increases construction cost. Often, the circuit breakers in an electric panel also serve as the off/on switches. Placing the panels in a remote location makes it difficult to determine what is being controlled.

Panels serving appliances also should be located as close as possible to the kitchen. In addition, should a circuit breaker “trip,” it can be quickly reset, minimizing disruption of the cooking operation.

Lighting
Lighting represents arguably the key element in establishing a restaurant’s ambiance. The variety of light sources and fixtures available today provides interior designers with an almost unlimited selection to achieve their desired effect and impact. Lighting design should be thought of as an Olympic sport that combines both technical and artistic scores to determine the overall quality of the result.

Selection of overall illumination level, color rendition, style of fixtures, brightness intensity and pattern of light distribution are typically the domain of the designer. However, consultation with an electrical or lighting engineer during the design phase will yield additional benefits beyond.

Longevity of the lamps selected, the efficacy of how the lamp converts energy into light, ease of lamp replacement and limiting the number of different lamps specified are key considerations. Complex lighting schemes that require frequent and complicated lamp replacements to maintain the desired “look” can be very detrimental to a restaurant’s operation. How do you replace lamps that are 15 feet above the floor and located where ladder placement is difficult? Time is money, especially when a lighting design requires an outside service to perform frequent relamping.

In the kitchen area, it is not ambiance but impact on operation that is the primary concern. Work areas should feature shadow and glare-less illumination. The ability to read orders, verify proper cooking/preparation of food items and check the presentation of plates before serving is greatly impacted by the lighting system. As stated in the discussion on HVAC design, finding the “peaceful coexistence” of diffusers and lights in the kitchen ceiling represents a significant challenge. Both the mechanical and electrical engineers should work with the kitchen designer to achieve a consensus design that meets everyone’s expectations.

So the next time you start developing a new concept, or contemplate a major revision to an existing one, think beyond the décor and ambiance you want conveyed to your guests. Include the logical — not just functional — development of the mechanical, electric and plumbing system designs as part of your design parameters.