Hotels and the hospitality industry go back as far as biblical times when Mary and Joseph arrived in Bethlehem during the census. The bible tells us they were refused accommodations because, “there was no room at the inn.” Since the beginning of time, people have traveled for many reasons.

The word hospitality comes from the Latin root meaning host or hospice. The first hotels were nothing more than private homes opened to the public. Most, unfortunately, had poor reputations. In Roman times, the inns and hotels began offering better accommodations to travelers to encourage visitors.

The first inn located in America was recorded in the year 1607. This was likely near the Jamestown settlement. Later, as the colonies grew, stagecoaches made frequent stops between destinations at roadside coaching inns for water, food and to rest the horses. In the larger towns and cities, patrons would stay in two-story wooden hotels or boarding houses.

As railroads were built, passenger trains would only stop at designated train stations in the city centers. This is where the railroads built many grand railway hotels. Other hotels soon sprung up nearby to handle overflow lodging and offer cheaper accommodations. Reports show the first publicly owned hotel was the City Hotel in New York in 1792. The first modern hotel, was the Tremont, which opened in Boston in 1809. And the first business hotel was the Buffalo Statler, which opened in 1908.

After the invention of the automobile, motor car traffic travelled along on the original two-lane roadways in the U.S. and they would pause at any camp, cabin court or motor car hotel (motel) along the way.

Although there were hotel brand names available, the cookie cutter brand name hotels got their start after World War II, when the U.S. economy was doing well and the interstate highway system was brand new. As returning soldiers purchased new cars and started families, there was a desire by many people to travel across the country to explore many of the new national parks and locations that were now easily accessible.

In 1951, a young and successful businessman, home builder and entrepreneur from Memphis, Tennessee named Kemmons Wilson, and his family, went on a road trip. Wilson found himself dissatisfied with the sub-par motels along his route. He was particularly unhappy with motels that added surcharges for extra towels and some even charged as much as $2 additional for each of his five children staying in the same room. That would be about $20 extra per child in 2018.

Wilson grew tired of dealing with different types of accommodations that had varied rates and different levels of cleanliness. During a stay at one particularly shabby roadside motel, Wilson envisioned a need for a chain of clean, affordable hotels along the new interstate highway system.  Since it was relatively new, there were plenty of empty lots adjacent to freeway exits.

In 1952, he decided to gather support and funding for his vision from Memphis area businessmen and he built the first hotel in Memphis, which he called the Holiday Inn after a 1942 Bing Crosby movie. His original hotel offered 120 rooms with air conditioning, television and telephone. Children under 12 stayed free with their parents, and the hotel had an outdoor swimming pool. Every Holiday Inn at the time offered the same features, amenities and rates, ensuring guests knew exactly what to expect from a night's stay. Wilson's hotels became so successful many of his competitors adopted his standardization model for their chains.

From there, a surge of hotels flooded American urban areas and the rest of the world with prominent names such as Radisson, Marriot and Hilton.

Over the years, several hotel types have emerged to serve niche markets, including budget hotels, business hotels, luxury hotels, banquet hotels, and convention hotels. Aside from the accommodation rates and amenities offered at each type of hotel, as a plumbing designer, you should consider the difference in size and the scope of water use required for the type of hotel being designed.

Hotel demands on the plumbing system

It is important to note that the plumbing utility demands and the hot water use in different types of hotels will drastically vary based on guest activities and events surrounding or within the hotel property. The variation in activities and uses can create a spread out or very short peak demand period for hot water and other utilities in, let’s say a convention hotel. For example, if every guest in a 4,000-room convention hotel is there for the same convention and needs to attend an 8 a.m. meeting, it can create a very high utility demand over a very short period of time when the majority of the guests are showering in the hour or two before the meeting.

Typical fixture unit loading will not work in the scenario above, because fixture unit values have been based on studies by Dr. Roy B. Hunter in apartment buildings. Apartment buildings will have a significantly different peak demand profile than a convention hotel, which must be accounted for in the design professionals plumbing system design. When the use profile of the building is not properly accounted for, the hot water temperature often drops as the demand increases beyond the design assumptions. This can be especially problematic with instantaneous systems where the peak demand is underestimated.

Sometimes the peak demand requires a bit of detective work by the design professional to ask lots of questions and do some research to try and determine the potential for concentrated peak demands. If you estimate wrong, someone will take a cold shower prompting a call to building maintenance, where a temperature adjustment upwards might put many people at risk of a scald burn. I had a salesman say to me once, “I have never had a customer call me at 6 a.m. and tell me they had plenty of hot water, but I have had a few calls saying they do not have enough hot water.” Sizing water heaters is not an exact science, but we know enough to make a pretty good educated assumption of peak usages. Peak flow demands also affect water flow through the booster pumps serving a domestic cold water system, and through the water heaters serving the domestic hot water system. A large scheduled event can also cause peak loads for other utilities like fuel gas, sanitary drains and sewage lift stations over a concentrated time. The potential peak demand is important to understand and plan for when sizing equipment and calculating friction losses in piping. This type of sizing information is not covered in the plumbing codes.

Hospitality kitchen plumbing design

Commercial kitchens in hospitality facilities are challenging designs. The plumbing systems design is almost as complex as one for a hospital and just about as critical for health and safety. Commercial kitchens come in many sizes and shapes, and are typically found in casinos, hotels, hospitals, prisons, large schools, corporate headquarter dining facilities or other large buildings serving many people.

Food service equipment consultants are often hired for large commercial kitchen projects. Proper planning and layout of a commercial kitchen can streamline operations by arranging the function and flow of the food service workers with respect to the equipment layout, which can streamline food preparation and save on operating and labor costs. The plumbing drawings for a large commercial kitchen have many pipes, valves equipment and drain connections. Both the design and installation portions of the project can be made much easier if a food service consultant is involved in the project from the beginning. I have worked on projects where the food service consultant was going to be part of a tenant finish-out package after the building was constructed, and we had to provide utility stubs to the kitchen for the future food service contract by a yet-to-be-named franchisee. In these cases, you need to plan and size the piping for the extreme case.

Sanitary drains need to be deep enough for piping grease waste sloped at a ¼-inch per foot slope to keep the velocity up in the grease waste pipes. When the drain locations are not confirmed, plan on the piping coming from the farthest corner of the space at a slope of ¼-inch per foot. Water piping needs to be stubbed into the space with isolation valves and sized generously. Often, when the hot water demands for a tenant finish space are not known, the water heater can be located in a mechanical space or janitor’s closet within the kitchen space.

When a food service consultant works on the project from the very beginning, they usually provide food service equipment layout drawings at the schematic and design development stages of the project. These drawings should give the plumbing engineer and contractor enough information to layout the piping, size the water heater, and locate and size the grease interceptors.

The final submittal from the food service consultant usually has a food service equipment plan with all the equipment identified with tags. In addition to the equipment layout drawing, there are typically separate utility connection drawings for plumbing, ventilation and electrical connections to the kitchen equipment.

Some food service consultants provide an equipment schedule on the drawings showing all the utilities and rough-in connection sizes. Sometimes this schedule may be published in spreadsheet format in the food service equipment book. The book also has copies or manufacturers’ data sheets for each piece of equipment in the kitchen and they are identified with a number. Look for a cover sheet for each food service equipment item that lists the equipment identification number, utility connection information, capacities, physical dimensions and the manufacturer’s name and model number information.

Model codes vs local codes

The one thing that seems to be constant for all commercial kitchens is that the requirements are different depending on where you are. I’ve worked on the plumbing design for many big box hyper-marts that had grocery and retail stores. We helped the owner develop criteria drawings that were the basis for all site-adapted stores, and then we site adapted stores for specific sites around the country. The stores were different square foot sizes based on the local market, and they were oriented with left-hand and right-hand floor plan layouts. They had lease spaces across the front for small businesses like restaurants, banks, liquor stores, barbershops, optical, etc. The interesting thing we found was, when we crossed state lines, county lines, and even city limits, the health department requirements and plumbing code requirements were different from one jurisdiction to another. This caused significant revisions to the plans, depending on the jurisdiction. Many of these issues should be incorporated into the model plumbing codes. Some of the different requirements that the plumbing designers had to deal with included:

Local plumbing code requirements for commercial kitchens:

1. Venting requirements for sanitary drainage;

2. Indirect waste requirements from food preparation and dishwashing sinks;

3. Grease interceptor sizing requirements and location;

4. Grease waste piping slope;

5. Distance from the farthest fixture to the grease interceptor;

6. Which fixtures were required to route to the grease interceptor;

7. Food waste grinder discharge requirements;

    a. Routed through the grease interceptor via a solids interceptor;

    b. By-pass the interceptor; and   

    c. Green plumbing advocates have promoted not using food waste grinders because of the energy the motors waste and the solution was to promote food scrap bins near pre-wash sinks.

8. The height of the floor sink above the floor (Some jurisdictions want floor sinks flush with the floor. Other jurisdictions want floor sinks ½-inch above the floor, some jurisdictions wanted floor sinks 2 inches above the floor, and one jurisdiction wanted floor sink rims 4 inches above the floor.);

9. Water heater sizing requirements (Some state health departments had water heater sizing requirements for food service establishments that greatly increased the storage and energy input requirements for water heaters.);

10. The number of hand wash sinks or the travel distance to hand wash sinks;

11. The location of employee restroom facilities;

12. Backflow prevention requirements for various pieces of food service equipment;

13. Floor drain requirements;

14. Water temperature requirements; and

15. The location of adjacent site utilities, including the domestic water size and pressure, and sewer size and invert elevations.

These were just a few of the code differences from one jurisdiction to another. I have also had the opportunity to work on several commercial kitchens for major casinos, colleges, hospitals, corporate headquarter facilities, airports and sports venues. Many of the new casinos featured numerous upscale restaurants in addition to large buffets or food courts. These casino buffets, have hundreds of menu choices and many different cuisine styles offered. The amount of food service equipment for these facilities is impressive. They have practically every piece of food service equipment you could think of.

At one casino, the facility engineer sent a sketch of a large concrete passive-type grease interceptor located outside of the building. It was larger than a railroad car! The sizing calculations used on that unit were based on his past experience, which showed that a large interceptor was required due to the quantities of greasy foods in the casino and the amount of time between pumping the interceptors. At which time, there was line-up grease hauling equipment and many pumper trucks to pump out the very large grease interceptor.

Interceptor sizing

Interceptor sizing and location is very inconsistent from jurisdiction to jurisdiction. There are areas of the country where the interceptor must be outside because of the obvious concerns about the odor from cleaning an interior passive-type interceptor. Many of the jurisdictions require an exterior grease interceptor to be a minimum size of 750 gallons. Some jurisdictions require a minimum size of 2,500 gallons. There were no consensus standards for the concrete grease interceptors with respect to design and coatings and performance. Most were simply a concrete septic tank. It is important to note that concrete is a porous material that may degrade when exposed to grease and oils, so any time a concrete interceptor is used, it should be lined with epoxy paint or an asphalt coating. There are jurisdictions that do not allow exterior grease interceptors because they were not listed to an industry standard and they have had problems with spalling concrete and grease coagulating in the building grease drain and building grease sewer piping before it gets to the grease interceptor outside.

Some locations require every fixture in the kitchen to drain through the grease interceptor, while other jurisdictions exempt the food waste grinder from the grease interceptor. Some require the interceptor to discharge through an interceptor after passing through a solids interceptor.

Some jurisdictions have required that only the wash compartment on a three-compartment sink route goes through the grease interceptor. This requires labeling the sink compartments so there are “wash,” “rinse” and “sanitize” compartments. If someone went left to right versus right to left with the dishwashing operation, most of the grease would by-pass the grease interceptor. The reason for limiting the fixtures flowing to the grease interceptor has to do with the size limitation of the grease interceptor. Larger units may not fit under a sink drain board and allow access cleaning.

I once worked on a kitchen renovation for a large college where the floor sinks, trench drains and other kitchen area floor drains needed to flow through a grease interceptor. The kitchen was located in the interior of a building that was almost a half-mile long and a quarter-mile wide. The invert elevation of an adjacent existing sewer inside the building and the extremely long distance to any exterior wall did not allow for a remotely located grease interceptor. The solution was to use a large grease interceptor with a grease removal device (GRD) located in a concrete pit under a nearby storage room. The GRD automatically removes the grease from the interceptor, thus reducing the maintenance on the individual unit. In this installation, the grease and oil were pumped through an underground heated tube inside a pipe sleeve to a remote barrel at the loading dock. The grease interceptor pit had a solids interceptor prior to the interceptor that removed the solids from the waste stream, ground them up through a grinder pump and discharged them to the outlet of the interceptor. This system required minimal maintenance besides changing the grease barrel at the loading dock at proper intervals, and periodic inspection and maintenance of the grease removal device, the grease removal pump, and discharge tubing to make sure they were operating properly.

Kitchen exhaust hoods

Another area in commercial kitchens requiring additional plumbing design and installation considerations is the kitchen exhaust hood wash down system. The systems typically require a domestic hot water connection with proper backflow protection to the wash down system control panel where detergent is injected into the hot water. The hot water mixed with detergent is then piped to a series of spray nozzles in the kitchen exhaust hood and the associated exhaust duct. These systems require a significant hot water load, but they are usually used during off-peak hours. The hood typically has a drain that is piped down to a floor sink near one end of the hood. The water supply to the wash down panel needs backflow prevention in accordance with the local codes. This is typically a reduced pressure backflow preventer when a detergent injection pump is used. Care should be taken to consider what happens to the emulsified grease and detergent when it is washed down. This hot water and detergent mixture can emulsify the grease in an interceptor and wash a lot of it downstream. This hood wash-down operation should be done immediately after a grease interceptor has been pumped out and then the interceptor should be pumped out again after the hood wash-down system has been cycled.

Backflow prevention

Contractors should check with the local codes for specific backflow preventer requirements. Many manufacturers leave it up to the plumbing engineers and contractors to design and install a system with proper backflow prevention for a given application. Special consideration should be given to water connections for dishwashers, potato peelers, food waste grinders with a water supply connection, hose connections, and ice machines.

There are local codes that require additional backflow prevention for various pieces of equipment. For carbonated beverage dispensers, for instance, the model codes recognize the internal ASSE 1022 backflow preventer provided with the major beverage distributor’s dispensers as an acceptable means of backflow protection. These internal backflow preventers are now included in most of the new carbonated dispensing systems. In some cases, code officials want an external backflow preventer so that they can be assured of protection of the water distribution system. Most codes prohibit a reduced pressure backflow preventer from being installed in a ceiling space. However, when a reduced pressure backflow preventer or vacuum breaker is used above a ceiling, a drain pan should be installed to catch any spilled water with indirect drainage to a nearby floor sink or drain.

Hot water

Sizing the water heaters for a hotel can be very challenging. Hotels have several areas that require domestic hot water with different temperatures and different peak times. Consideration should be given to having separate water heaters for the different hot water uses in the facility. There are numerous references for sizing water heaters serving food service equipment. The ASPE Domestic Water Heating Design Manual, the ASPE Plumbing Engineering Design Handbook, manufacturers’ catalog sizing guidelines and some state health codes all have hot water sizing criteria. It should be noted that the model plumbing codes do not give sizing criteria for hot water systems or water heaters.

Be careful when sizing systems with hot and cold water hose stations for clean-up. Experience shows that it takes approximately one tank of hot water to wash down the floors. In similar large facilities with different sized water heaters, a study was done to determine how much hot water is used for washing down the cooking and food prep areas. Meters were installed on the water lines to the water heater, and the staff was not told of the study. It seems they washed down the floor until the hot water ran out. Where there was more hot water, they used more. Most food service equipment manufacturers list the hot water demands for their equipment. Large hot water users are dishwashers (especially conveyor type), hood wash down systems, hot and cold water hose stations and large pot sinks.