Doors and windows are typically a customer’s first impression of an establishment and play a part in setting the tone of a visit.
As the initial touch point, the quality and overall condition of exterior doors provide a tactile cue to the visitor about how the restaurant itself is functioning. In this case, it is usually less about the door’s aesthetics than it is about the mechanics and ease of use. That said, exterior doors should reflect the restaurant’s personality and be consistent with the brand.
Broadly speaking, doors and windows should complement the building’s architecture. This is even more important than being consistent with the restaurant’s interior design.
It’s imperative that these components adhere to building codes, which will vary depending on the restaurant’s location. Local codes with regards to doors and windows are generally based on energy efficiency and climate while also taking into account extreme weather conditions.
Window & Door Types
Restaurant doors include kitchen doors, walk-in refrigeration doors, back doors for receiving and staff entrance and exit, front entrance doors, patio doors, and, increasingly, garage or retractable doors that blur the line between outside and in.
Among the most common types for restaurant use are revolving doors in automatic, manual or security versions, with the latter detecting, preventing and controlling unauthorized entrances. While grand revolving doors in center shaft or center core vestibule designs accommodate heavy traffic and provide energy savings, manual revolving doors are affordable as well as energy efficient.
High-volume operations may be best served by automatic swinging or sliding doors. While sliding doors have a standard configuration, swinging doors can be inswing, outswing or parallel inswing, depending on use.
Also in the door category, air curtains are typically specified for use in the back of house. Along with frequent use in service entries, air curtains can be installed within walk-in coolers to ensure inside temperatures remain consistent when doors are open. Air curtains also can be used in conjunction with pest control companies for integrated pest management programs. Typically, health departments require NSF 37 air curtains installed 3 feet above the threshold and mounted on the outside of the doorway. Drive-thru windows sometimes utilize air curtains not only for employee comfort in inclement weather but also to protect nearby equipment from freezing temperatures during the winter.
Standard air curtain sizes are 36, 42, 48 and 72 inches wide but can go up to 120 and 140 inches for wider openings. These are constructed of anodized aluminum, stainless steel or galvanized steel, and some offer custom colors to match the restaurant’s aesthetic and brand.
Also part of this category, retractable or garage doors have evolved to be full-scale retractable glass enclosures, allowing restaurants to have all-weather spaces and never lose seating due to inclement weather. Built custom for the space, these enclosures are usually made of glass, aluminum and polycarbonate, with a wide variety of colors and designs available.
Like doors, there are a wide variety of window types geared to restaurants. Single- and double-hung windows are the most common types, have less open area as compared to casement and slider windows and are more prone to air leakage than casements. While the single-hung type has a movable lower sash and a fixed upper sash, double-hung windows have two movable sashes with the upper sash sliding down. The main advantage of double-hung windows is somewhat better ventilation. Air flow is constant when both double-hung sashes are opened about halfway. Double-hung windows also are easily cleaned without a ladder. Because only the bottom sash slides upward in a single-hung window, this type can experience higher air leakage rates.
Fixed or picture windows do not open or close but allow outdoor views and light into a space. When properly installed, these windows are airtight and provide no ventilation.
One of the most popular types in commercial foodservice, casement windows include shutters attached to the frame with single or multiple panels. Similar to awning windows, casement windows open out, so these should not be situated in high-traffic areas. This type offers ventilation, but also can be sealed shut to save energy. Because the sash presses against the frame when closed, there is low air leakage. A type of casement window, the sash type, features fully-glazed panels along with top, bottom and intermediate rails.
Operated with a crank, awning windows are usually a part of the bottom, sides or top of picture windows. This type provides additional ventilation when needed, yet seals air in more effectively than sliding windows. These are hinged at the top, opening outward, which prohibits use in walkways or areas with customer traffic.
Slider windows open sideways, providing ventilation when needed and views to the outdoors. Although they are not as airtight as casement windows, this type is affordable and easy to operate.
Drive-thru windows in automatic and manual versions offer standard self-closing mechanisms and lock automatically.
Common Materials
Although wood and metal are staple door materials, the sky is the limit in terms of construction.
Window frames in metal, wood, plastic and fiberglass are the most common. Vinyl, wood, fiberglass and composite materials provide the best thermal resistance. Metal offers durable construction and is practically maintenance free, but this material is a poor insulator due to its heat conducting capabilities. Wood frames provide good insulation but require regular maintenance. Frames using composite wood products, such as particleboard and laminated strand lumber, are sturdy with similar thermal properties as traditional wood but with better moisture resistance. Fiberglass window frames can be insulated for energy efficiency and performance while vinyl frames resist moisture and provide easy maintenance. This type can be insulated for energy efficiency.
Windows have a variety of glass options, depending on use. Used most often in restaurants, tempered glass is four to six times stronger than glass used in residential windows. When laminated, it offers additional protection in the event of a natural disaster such as a hurricane.
The number of glass panes that make up the window are referred to as glazing, with single, double, triple and more available. The more windowpanes, the greater the noise and heat insulation. Multiple pane glazings that combine plastic with glass are more affordable and provide easier installation as compared to windows that are all glass.
Restaurants can choose to tint windows, which not only eliminates glare but also minimizes heat from the outside and provides a level of privacy. For sunny locales, reflective glass coatings reduce heat and offer privacy, while low-E coated glass blocks sun’s heat without interfering with outside light.
Trends and Innovations
Windows with a vintage appearance have become more popular in recent years. In addition, types with an industrial look are more prevalent. Black window frames, which are commonly used in residential projects, are now trending in commercial restaurants.
Also, the use of vertical slider doors is becoming more widespread, along with finely-detailed components for hinges, pivots, door frames and jams as well as custom door pulls.
Purchasing Considerations
There are a number of factors to keep in mind when choosing doors and windows for restaurant operations.
First, determine the sizes that are needed for each space. In some cases, these may be standard, while others may require customized products. Local codes and requirements should be taken into account.
Doors and windows should not be intrusive to customer traffic when open. Make sure doors swing in the appropriate direction and not into common spaces.
Thermal and acoustical qualities come into play. Look at typical weather conditions in all seasons to see what type of material, format and insulation will work best. Note the noise issues and whether acoustical segregation from the street or other interior areas is needed.
For more open views and to bring the outside in, consider adding reflective coating on glass windows. Also, digital prints or patterns on windows can add eye appeal, while also diffusing incoming light from the outside.
For windows, cleanability is a factor, and those that tilt in are easier to maintain.
A common mistake when choosing windows and doors is not considering the weather conditions of the locale. For areas with heavy wind, torrential rain, etc., windows and doors should have adequate insulation. Some locales, like New York, have energy compliance requirements for facades and windows.