The Art of the Soft Sell

It may seem silly to infer that an upscale retailer such as Saks Fifth Avenue and a mass merchandiser such as Wal-Mart have anything in common, other than the fact that both are retailers. However, a look at their operations reveals a common theme: both have taken to heart and perfected a key tenet of successful retailing—presenting products that people want in an appealing, comfortable e...


It may seem silly to infer that an upscale retailer such as Saks Fifth Avenue and a mass merchandiser such as Wal-Mart have anything in common, other than the fact that both are retailers. However, a look at their operations reveals a common theme: both have taken to heart and perfected a key tenet of successful retailing—presenting products that people want in an appea ling, comfortable environment that keeps them coming back.

At the heart of this formula is a delicate balance between what it costs to sell merchandise, and how much can be charged for that merchandise to cover those costs, as well as generate a profit. Chief among these overhead costs is the facility itself, beginning with design and construction, and continuing with operations and maintenance. Many individual considerations go into such a design, but in the final analysis, the goal is to create a memorable, positive experience for consumers.

The shopping experience

While there are many reasons why shoppers visit a particular retailer, one of the reasons they linger and return is the level of comfort they feel in the environment. The positive impact achieved by a great product selection, competitive pricing and an appealing and functional store design caThe way M/E systems are designed for retail facilities—to create a comfortable environment where shoppers are encouraged to spend more money—mainly depends on the store layout, which runs the gamut from warehouse/big box to partitioned department stores to high-end boutiques. But in all cases, HVAC, lighting and security must be integrated in a way that is the most operationally efficient and compatible with the store
n be dampened and even negated by excessive heat, stifling humidity or bone-rattling chill. These are often referred to as "stressors," which can also include sound and light issues. The goal of designers is to minimize these stressors and maximize the comfort level.

But while retailers of all sizes and categories, for the most part, are attuned to how their indoor air quality impacts their bottom line, there is still a desire in large segments of the retail community to minimize costs in areas not visible to customers, such as HVAC systems. For that reason, the vast majority of retail space in the United States is outfitted with packaged, single-zone, rooftop HVAC units. These units provide constant, dependable and relatively inexpensive temperature control. The downside of these constant-volume systems is that while they are effective for temperature control, they are ineffective for humidity control. Consequently, improper sizing, especially in warm humid climates, results in unacceptable humidity in the store.

Humidity control, of course, is more of an issue for upscale retailers, where the space is typically smaller and may include more partitions and architectural features that can trap air and create hot spots. For these retailers, it is not uncommon to find custom-designed or variable-air-volume systems that can handle more variations in heating and cooling loads and provide tighter control. For example, anchor stores in malls will occasionally go to higher efficiency systems, such as chilled water, to handle the needs of their more complex floor plans, layouts and operating schedules.

Another reason upscale retailers are often willing to pay for a more optimized, controllable system is that they are not designing cookie-cutter facilities, nor are they tied to the tight economics of a prototype rollout program. They are also more interested in the longevity, serviceability and operating efficiency of their equipment, rather than just the first cost.

Technically, there is no difference between building code requirements and the types of systems that are used in retail facilities and other business or commercial facilities. However, in retail, architects and space planners have to make accommodations for the design and use of the space. Likewise, M/E engineers must coordinate their specifications with these design goals. In specialty and upscale retail, for example, there is more of a desire to blend air-handling systems and devices into the architecture, and even hide them when possible. A fairly simple and common way to do this is with light fixtures that integrate diffusers and slot returns. Also common, but more complex, is using architectural features such as ceiling coves to hide light fixtures, lamps and HVAC diffusers.

Inviting customers in

One feature that retailers never want to hide, and which must be accounted for in system design, are the front doors. In contrast to commercial businesses, whose doors may open to an interior hallway, and to mall stores that open to an air-conditioned concourse, many retailers' doors open directly to the outdoors. This direct exposure to outside air, plus exposure to contaminants such as vehicle exhaust, makes the maintenance of interior air and humidity at acceptable levels a challenge and puts added pressure on mechanical equipment.

A common way to mitigate this situation is to include front door vestibules. The effectiveness of this concept can even be enhanced somewhat by increasing the distance between the exterior and interior doors. Variations on this concept may further facilitate keeping inside air in and outside air out. For example, a large grocery chain in the Southwest specifies that its vestibule doors be at 90° angles to each other to further reduce the flow of outside air into the interior.

Internal or negative pressurization is another common method to ensure that conditioned air, and not the reverse, is the air movement in and out of the building. Some retailers favor an air curtain, literally a vertical wall of air at the doorway that stops transfers of air. Neither of these methods, however, is 100% effective, and retailers and their consultants must also consider back doors and loading dock entrances, which are often left open for long durations to allow for deliveries. These back areas must be designed so they don't draw air from the loading dock into the retail space, or worse, suck outside air in through the front doors.

Deciding on air distribution

Another unusual HVAC concern arises from the fact that some retailers have areas that generate intensive heat gains, such as departments that sell TVs, computers and other electronic products. Accommodations must be made for these settings with increased air volume and exchange. At the same time, jewelers who typically have high lighting requirements also need systems that will offset the resulting heat gains. What they don't want, however, is a high output system overhead that puts their valued customers in the middle of an annoying downward draft.

Air distribution, in general, especially for low-price retailers that favor a warehouse-style retail facility, is challenging. The question that consultants must raise and help answer is whether the facility should be designed with drop boxes or ductwork from the air-conditioning system. In one scenario, a retailer favored drop boxes to save on the added expense and the unwanted look of exposed ductwork. However, airflow and throw analysis determined that the air volume produced by the packaged systems would not be sufficient to prevent hot spots between the drop boxes. The recommended solution was limited ductwork, optimizing the cost of ductwork and achieving adequate, even air distribution.

A breath of fresh air

Ductwork and HVAC are not only important to a store's design from a customer comfort perspective, they're necessary components to meet mandatory IAQ standards.

In the past decade, the minimum ventilation requirements in building codes have increased significantly. In the 1980s, for example, the minimum required ventilation was typically 5 cfm per person. But in 1989, ASHRAE published Standard 62-1989, which upped the minimum recommended ventilation rates for retail spaces.

The new standard was based on floor area, not occupancy. For basement and street-level sales floors, the new recommended minimum ventilation rate was 0.3 cfm per sq. ft., and for upper sales floors, 0.2 cfm per sq. ft. The end result for most retailers was a two-fold increase of the recommended minimum ventilation in retail sales areas. The increased outdoor air volume necessitated higher capacity heating and cooling equipment.

Retailers employing direct expansion (DX) type air-conditioning equipment, especially those located in hot-humid climates, were affected in three ways:

  • Higher initial cost of HVAC equipment.

  • Higher operating costs.

  • A loss of humidity control.

The combination of continuous outdoor-air ventilation and the cycling of DX equipment—compressors, particularly during moderate or mild weather conditions, can lead to unacceptably high humidity in the store. In fact, a relative humidity greater than 60% is not uncommon for these situations.

Some DX equipment manufacturers have developed cost-effective alternatives to their standard units that are designed to better control humidity. One option is the addition of a hot gas reheat coil built into the air-conditioner, controlled via a space humidistat. Other solutions are available, but they must be carefully engineered in the overall function and use of the building.

Securing the goods

As important to retailers as keeping their customers and employees comfortable is keeping their merchandise safe and secure. Shoplifting and theft—like expensive, ineffective mechanical systems—eat away at the bottom line, increase operating expenses and potentially put upward pressure on prices, which in turn impacts product appeal.

There is no way to completely defeat theft, as professional shoplifters can remove or disable product control sensors, cut cables on clothing and elude security cameras and personnel with amazing ease.

While theft cannot be completely defeated, it can be deterred by increasing the risks of attempting it. The risks faced by would-be thieves fall into two broad categories: open environments and closed environments.

Open environments employ passive resistance, which is not a facility design issue, but rather a matter of how and where products are displayed, how staff is trained and where they work within the space. However, it is interesting to note that within the broad category of open environments, deployment of passive-resistance methods sometimes are based on the same general facility conditions that prompt the selection of certain building systems. For example, a large, open floor plan that benefits from single-zone, packaged, rooftop HVAC units also may be a prime environment for broad-scanning security cameras. Likewise, tighter, compartmentalized floor plans that need a more customized HVAC system also may need a more customized security system and plan.

Regardless, retailers should not depend solely on devices and technology. Rather, they should practice vigilance, have security staff on the premises and be careful not to design floor plans that have dead corners.

The second type of security environment—the closed environment—keeps products enclosed, for the most part, and requires lighting and other display techniques within glass cases to make the merchandise visually appealing.

In this environment, temperature control and air quality come into play in a very real way. To display products in an appealing manner, lighting must be introduced into display cases. This creates heat gain within and from the case that not only is uncomfortable to browsers and employees but can actually damage some products. For example, gemstones in a jewelry case can change physical appearance, while fine fabrics and leathers can fade or become brittle and dry.

To counter these impacts, additional cooling, venting or exhausting is needed. These techniques are nothing new in the retail world, but can sometimes create new problems. For example, a system that draws cool air into the case can also bring in outside dust, diminishing the beauty of jewelry and dirtying the dark-colored felt that it's typically displayed on. For this reason, retailers and their consultants need to consider product types and the frequency that the case is opened and cleaned when planning the type of display cases and cooling systems to be used.

Display windows are another way to show merchandise, but this option requires an added measure of security. However, whether for security or just for show, display windows, like smaller display cases, raise a number of environmental questions: What types of products will be displayed, what will be the heat gain from lights and how often will the window be entered for cleaning or product changes?

When considering security, retailers must strike a balance between securing their merchandise and making it sellable. The best consultants will go the extra mile to find out the retailer's selling philosophy and then prepare designs that accommodate that philosophy.

Controlling the retail environment

The nuances of designing an effective retail environment are certainly complex, but thanks to computers, networking and the Internet, controlling the retail environment is more precise than ever before, and is also more mobile. One of the nation's top retailers monitors the lights and mechanical systems of its individual stores from its corporate office. And, as they introduce new store concepts, they can compare operations at a test store to help existing stores implement new best practices.

Taking control a step further, HVAC, lighting and security systems can be integrated into a single system for more efficient operations and maintenance—both on site or remotely.

In all of these matters, the real issue for consultants is not the systems to design and specify, but formulating a plan for how and why to spend money that meets the retailer's sales goals. In other words, the design professional must work with the retailer to find the best balance between effective system design and the desired retail environment.

A New Decorative Lighting Option

Offering an aesthetic alternative to the large generic fixtures commonly found in retail environments, particularly big-box stores, lighting manufacturer Holophane has come out with a decorative, customizable lighting option.


These 92%-efficient fixtures, made of borosilicate glass, come in five basic prismatic glass shapes and can be mixed and matched with different colors of decorative claws, caps, ballast housings and mounting conf iguration options to create a unique look either for the store as a whole, or to distinguish individual store departments.

In addition to the fixture's customizable and decorative features, in its quest to contribute something "new and different" to the market, the lighting manufacturer is also offering:

Two fixture sizes—16-in. and 10

Compatibility with a standard, pulse-start or electronic ballast and 70- to 400-watt metal-halide lamps, 26-and 42-watt compact-fluorescent lamps and 300-watt and 500-watt incandescent lamps.

A range of photometric distribution, depending on the optical design, including 75% downlight and 25% uplight, 70% downlight and 30% uplight, 60% downlight and 40% uplight, 50% downlight and 50% uplight, 10% downlight and 90% uplight.

The Psychology of Comfort

The psychology of the impact of temperature on customer satisfaction and retail participation has been well studied by retailers. With checkout areas typically near the front doors, many grocery store designs call for added air conditioning in these spaces to keep employees and customers comfortable and happy. With customers facing the potential of a long check-out line and a large bill from a cart full of groceries, the last thing they need is the added stress that can be caused by excessive temperatures or humidity.

Dressing rooms, however, are all too often overlooked when it comes to addressing the customer's needs. Typically, th

It is important to note that a "comfortable" temperature is a matter of local definition; what is considered comfortable in Texas isn't necessarily comfortable in Maine or Wisconsin. When engineers look at the design criteria for a location, this is an issue that is often overlooked. Often the figures aren't adjusted, and instead, are input into cookie-cutter programs where facility design, construction and operating procedures are standardized to maximize economics and efficiency, and so the acclimatization of the local population is not considered.

Retailers and their consultants should consider these issues when designing systems for retail space.

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