Warewashing may be the least glamorous area in foodservice, but it shouldn’t be overlooked.

No customer ever comes to a food-service operation because of its warewashing prowess. Rest assured, though, customers won’t come back if this part of the business fails to pull its weight. 

Smooth-flowing warewashing operations happen by design. Failure to properly clean dirty dishes, glassware and silverware will compromise customer safety. Warewashing stations or dish rooms that can’t keep up with the volume will likely result in the operation having service issues. In other words, interrupting the flow of a warewashing area likely compromises the efficiency of the entire operation.

“Warewashing is one of the most thankless jobs in the kitchen, and it’s usually low-paying with a high turnover rate,” says Phillip Landgraf, executive principal, Ricca Design Studios, Greenwood Village, Colo. For the staff’s sake, “it needs to operate consistently, easily and as fast as possible.” 

This is why a dish room’s importance in an operation’s design cannot be overstated. “Whether it’s just a three-compartment sink in the corner or a full-blown flight machine washing thousands of dishes a day, this area is the base of the pyramid for an operation,” says Michael P. Salvatore, senior director at Ruck-Shockey Associates, Inc., Truckee, Calif. “It’s the foundation and where everything starts.”

The key is having the appropriate equipment to ensure tableware, utensils, pots, pans, etc., are sanitized and safe to use in a timely manner. “If a warewashing station is not designed properly, it will be a choke point in the kitchen,” says Gary Jacobs, principal at Jacobs Doland Beer, New York City.

The goal is simple: Process soiled dishware, silverware, glassware, cookware and utensils quickly, efficiently and with minimal breakage. The design also must keep a la carte stations supplied at all times. “Pot washing can be in same area or separated, and the same things apply,” Jacobs notes. “There should be a good flow that allows the wait and culinary staff to drop off items easily without crossing other stations if possible.”

Sizing, Flow and Setup

Volume is the first thing to address during the design process. The number of covers and meals an operation serves daily helps determine the warewashing station’s scale. “The appropriate dishwasher is needed to handle peak volume,” Landgraf says.

Another critical component to the layout is a well-designed, well-organized drop-off or sorting area, which includes a scrapping table. “This needs to be at the front end of the flow,” Salvatore notes.

Determining the paths of dirty and clean items in and out of the warewashing station is essential. “It’s important to make sure clean and soil paths are clearly separated with no intersection to cause cross-contamination,” Landgraf says. “Certain jurisdictions have strict regulations for distances from clean dish tables to the soiled side.”

Dish rooms often sit adjacent to an operation’s back door, which can be near to where staff take out the trash. In these instances, it’s important that the area with clean items is well separated from the flow of the trash. That’s why when assessing travel paths, Salvatore also considers doorways to see where items will be coming in and going out. “There needs to be a smooth flow,” he says. “It may be right to left or left to right, but it shouldn’t go backwards at any point.” 

An operation’s volume will determine whether a high-volume conveyor warewasher, single-tank machine or three-compartment sink is suitable for the station. There may be more than one solution and multiple machines. “I like to separate glass washing because the rinse tank on a dedicated glass machine will be cleaner,” Jacobs says. “This may need its own line for drop-off and drying.”

In some cases, Jacobs will specify an undercounter glass washer. “This may be located underneath the soil dish table between prerinse and entry to the warewashing machine or can also be adjacent to the warewashing station,” he says. 

Landgraf prefers stations with separate warewashers, one solely for plates and the other for silverware and glassware. “Because plates tend to be more soiled, this eliminates repeat cleaning cycles,” he says.

If a three-compartment sink is used in addition to or instead of a warewasher, it also must be appropriately sized. “A tri sink must be large enough for the biggest item, typically a stockpot, to be fully submerged,” Salvatore says. “We’ve had many people go smaller, but this is a mistake.”

Fully submerging an item plays a key role in properly sanitizing it. “For ease of use, having a deep sink bowl provides more room for items,” Salvatore adds. “Staff also won’t have to change out the water as often since there’s more of it and waste is better distributed.”

Drying and Storage

Critical aspects of the design that are sometimes overlooked include having the appropriate space for drying and clean storage. “Dishware and silverware have to air-dry; there shouldn’t be a risk of cross-contamination from using dirty rags,” Landgraf says.

Using a drying rack after sanitizing can help avoid problems with stacking wet items, known as wet nesting. “If a bunch of sheet pans are washed and stacked wet, any bacteria that was not washed off is trapped in a hot, wet environment. And that’s when bacteria can grow,” Salvatore explains. “Wet nesting is the enemy.” To prevent this, he often incorporates rolling or wire racks into warewashing station design. “This way, everything can be spread out in a single layer to completely air-dry. Unfortunately, many operations will skip this step due to lack of space.” 

The type of plates can impact the amount of drying space necessary. This is because china or porcelain dry quicker than melamine.

At the end of the line is storage, which should be large enough to hold all clean plates, glasses, silverware, pots, pans and utensils when everything is put away during closing hours, Jacobs says. “Adequate storage is essential so as clean product becomes available, it can be stored on appropriate shelving, such as wire or rolling racks,” he says. “These should be close to the warewashing and pot-washing lines. The same clean storage should be readily accessible to culinary staff without them having to enter the warewashing area.”

The flow of clean items into their proper storage spaces should not cross paths with the flow of soiled wares to the dish room, Jacobs adds. “Ideally, the warewashing and pot washing should meet together at a clean station,” he says. “There should be a pass-through shelf accessible to culinary staff so they don’t have to enter the warewashing area where there are dirty items.”

Jacobs prefers designs with a path that’s a short travel distance for waitstaff to drop soiled dishware that includes a sink for handwashing in between. The same setup is used for kitchen staff when dropping dirty pans for washing. 

In addition to assessing travel paths, safety and ergonomics come into play with warewashing station designs. “It’s important that floor draining is appropriate to avoid staff slips and falls,” Landgraf says. “We include floor mats on tile floors for this reason.”

Jacobs prefers seamless floors made of rubber or epoxy for added slip prevention. “We can coat this material up the walls to create a shallow basin as opposed to using wall tiles, which aren’t as durable,” he says. “These synthetic products are ergonomic, so we can avoid using rubber mats.”

When possible, Jacobs prefers stainless-steel walls in dish rooms. “PVC is somewhat effective but doesn’t seem to hold up as well over time,” he says. “We don’t want to see paint and tile in these areas as these have long-term maintenance issues.” If tile is used, he recommends that it be textured for a non-slip finish and use an epoxy grout.

Ventilation is another consideration as equipment in these areas consistently produces steam and heat. Landgraf recommends a system that provides a couple air changes per hour to ensure a comfortable environment.

“Everything ideally goes through a mechanical exhaust,” Jacobs says. “Each washer exhaust will have a dedicated run. We can merge into a Type 1 exhaust through a mechanical damper in some cases, but local codes should be followed.” 

Critical Components

This station may include other, less visible elements. For example, the warewashing process typically begins in the scrapping area, where spray arms prewash soiled dishware. “I like to include a basket over the sink to catch large food particles so these don’t clog the drain,” Salvatore says. 

Dishes then go directly into the warewasher or staff place them in a racking system. Smaller operations may use a three-compartment sink for washing, rinsing and sanitizing prior to dry racking.

“It’s important to confirm the right adjacencies are available for things like grease traps,” Jacobs says. “Grease traps are typically remote, but in some designs, we have to look at situating them locally, such as recessed into the floor, for better access.” If they can’t be recessed in the floor, grease traps are best located under mobile storage rather than below stationary dish tables, which are harder to move, he explains. 

There are also differences between warewashing stations in commercial versus noncommercial operations. “Institutional spaces have higher volumes and may utilize trays,” Jacobs says. “For these projects, we consider a longer machine with an integral prerinse and may add a blowdown system to dry items as they are discharged.”

With larger warewashing machines, items may not load into individual racks but instead be fed into a constant conveyor line. “Also, institutions may utilize a separate pot-washing machine, which is helpful in high-volume operations,” Jacobs adds. 

Salvatore says the main difference between commercial and noncommercial warewashing stations is the scale. “While a small pizzeria may only need a tri sink, a big hotel may have a 35-foot flight machine to run thousands of dishes from numerous restaurants and a catering operation,” he says. “There also may be multiple dish rooms, but all would have the same basic components.”

Landgraf adds that in addition to conveyor machines, larger noncommercial warewashing stations may incorporate tray and scrap accumulators as well.

Equipment Innovations

Warewashing designs are incorporating updated technology that is more energy efficient and environmentally friendly. “Ventless and heat recovery technology are huge,” Landgraf says. “When I started in the business, warewashers were using 300 gallons of hot water an hour. Now, with heat recovery, hot water is only needed to start the process, and the heat from it is reused.” He adds that with more efficient rinsing technology, the 300 gallons needed has been reduced to 100 gallons.

“We often see the ventless equipment that integrates internal circulation when we can’t utilize a traditional mechanical exhaust,” Jacobs says. “This collects the steam and uses it to heat the tank, which saves energy.”

“Equipment manufacturers have updated conveyor belts with cleaning systems,” Landgraf says. “I’ve also seen a couple companies test out robotics, which is the golden goose people are looking for.”

Salvatore adds that although robotics is not common, he’s heard of its use in identifying different food particulates for better cleaning. “Newer technology can distinguish harder-to-clean food debris, like dried egg from ketchup, to determine whether it needs presoaking,” he says. “However, this technology can be pricey.”

Salvatore always approaches dish room designs with intention because these areas are so vital. “Warewashing stations are often overlooked,” he says. “When they are well-staffed, no one thinks about them, but when they are not, everyone hurts. It impacts speed of service, safety, stress and the overall customer experience. If you treat it as an also-ran, the results will ripple through the operation.”