Hotels and Motels Introduction
Water savings potential varies greatly at hotels, depending on the type of facility and the how guests use the hotel. Guest rooms are not the only area to find potential water savings. Many larger hotels have significant water use resulting from banquets, conferences, restaurants, nightclubs, day spas, etc. It is important to not treat all hotels and motels with ‘cookie cutter’ type projects; as each hotel has different functions and water use patterns.
An effective strategy for large hotels should start with a grouping of functions for the facilities to better understand how water is used, and the water conservation potentials within each group. The purpose is to analyze all of the uses in an organized manner, while analyzing each building or facility according to its specific water use profile. An initial conservation plan might be outlined as follows:
1. Guest Rooms
c. Shower heads
| 2. Landscape irrigation
a. Near buildings
b. Parking lot medians
d. Recreation facilities
e. Golf course
3. Office and Staff Areas
4. Food Services
b. Pre-rise spray valves
c. Food steamers
d. Ice machines
e. Wok ranges
5. Conference & Banquet
| 6. Special Facilities
c. Cooling Towers
d. Exercise Gyms
Water savings can be achieved by replacing older model toilets using 3.5 GPF (13.2 LPF) or greater with new ULFTs (1.6 GPF (6.1 LPF)), HETs (1.28 GPF (4.84 LPF)), or dual flush toilets using 1.6 GPF (6.1 LPF) for solid waste and 1.0 GPF for liquid waste. The benefit-cost ratio is dependent upon the frequency of use; the frequency of toilet flushes per toilet varies greatly from hotel to hotel, and from guest room bathrooms common area restrooms. It is reasonable to assume an average of 6 to 7 flushes per guest, but it is not reasonable to assume all flushes occur inside the guestroom. A guest at a small motel will spend most of the day away from the motel; resulting in only 2 or 3 flushes/day/guest inside the guestroom. Guests of a resort type hotel will often spend a larger portion of the day at the hotel; resulting in 4 to 6 flushes/day/guest. Hotels catering to business travelers will average only one guest per room; while resort hotels often attract couples and families averaging 2 to 4 guests per room. Conference and banquet type hotel will attract many visitors beyond those staying overnight in guestrooms, leading to increased use of common area restrooms. All of these factors have to be considered when projecting water savings from toilet retrofits.
When conducting benefit/cost analyses on common area toilets, it is important to separate the calculations for female toilets versus male toilets for two reasons: (1) the ratio of men’s room toilets per male user is usually different than the ratio of women’s room toilets per female user; (2) men will most often use urinals (when available) rather than toilets. While it is reasonable to use average toilet usage estimates for program planning; performing toilet retrofit projections on hotel common areas requires calculations based on unique site data. A sample calculation for common area restrooms might be:
Average 300 male visitors/day, 200 female visitors/day
10 male toilets, 20 urinals
30 female toilets
Assuming 2 flushes/visitor/day in common areas (conference rooms, banquet rooms, restaurants, lobbies).
Male Toilet Flush Quantities:
364 days X 300 males X 0.25 toilet flushes/day = 27,300 toilet flushes/year
27,300 flushes / 10 toilets =
2,700 flushes/year/male toilet
Male Urinal Flush Quantities:
364 days X 300 males X 1.5 urinal flushes/day = 163,800 toilet flushes/year
163,800 flushes / 20 urinals =
8,190 urinal flushes/year/urinal
Female Toilet Flush Quantities:
364 days X 200 females X 2 toilet flushes/day = 145,600 toilet flushes/year
145,600 flushes / 30 toilets =
4,853 flushes/year/female toilet
Conclusion: This example shows replacing female toilets will garner nearly twice the water savings compared to male toilets, and urinals replacements are probably the most effective strategy of all.
The predominate type of toilet in office buildings is flushometer valve toilets and pressure-assist toilets, though gravity-tank toilets are found occasionally. Both the bowl and the flush valve of the flushometer valve toilets must be replaced to assure water savings and adequate flushing performance. The cost to replace a flushometer type toilet usually ranges from $250 to $400, depending on the type of toilet required. Wall-mounted flushometer valve toilets are the most commonly found in new buildings; while floor mounted toilets are more common in older buildings.
As with all toilets in the commercial sector, there are a few extras items to consider:
- Building maintenance staff must be trained to only use the proper parts when servicing the flush valves, or all water savings will be negated. Unfortunately, 3.5 GPF (13.2 LPF) parts often fit the new 1.6 GPF (6.1 LPF) flush valves.
- Replacement options include the 1.6 GPF (6.1 LPF)toilets, and there are now hundreds of models of HETs available (1.28 GPF (4.84 LPF) models and dual flush) While there are many gravity type toilets suitable for light commercial applications, flushometer valve types or pressure-assist models are preferable in most commercial buildings.
- Sensor-activated flush mechanisms often result in more frequent toilet flushing than manual flush valves. There is no evidence the sensor-activated valves save water.
- If installing dual-flush toilets, it is wise to post instructions for the toilet users.
- Disposable seat covers and paper towels are the most common causes of clogged toilets. Consider alternate methods of hygiene (sanitizers, continuous roll seat cover dispensers, hot air dryers, etc.), or select new toilets models that exceed 500 grams in MaP Testing.
- Flushing performance is very important for success. Refer the MaP testing before selecting new toilets.
The benefit of replacing urinals is highly dependant on frequency of use and the type of replacement proposed. Frequency of use is determined by calculating the quantity of male 8-hour shifts, the average urinal flush per man per 8-hour shift (usually 2 to 4), and the quantity of urinals. Similar to toilets, visitors to the facility might affect additional urinal flushes.
There are many options now for urinal replacements; from simply replacing the flush valve to reduced flows, to replacing the entire fixture with a high-efficiency urinal (HEU), which includes both flushing and non-water urinals. All options vary in the costs and benefits. In many cases, marginal water savings can be achieved by simply retrofitting the urinal flush valve to a lower GPF diaphragm on flushometer valve urinals, though some older urinals will not properly function at these reduced flows. Unfortunately, this type of valve-only retrofit can be easily and mistakenly reverted back to the higher flush volume during routine maintenance. Much consideration is needed to determine the best retrofit or replacement for any given restroom. To assure water savings are sustained over time, the best strategy is to replace the entire urinal and flush valve with an HEU (e.g., 0.125 GPF or 0.25 GPF (.47 LPF or .94 LPF) model, or a non-water urinal).
As with all urinals in the non-residential sector, there are a few extras items to consider:
- Building maintenance staff must be trained to only use the proper parts when servicing the flush valves or all water savings will be negated. Unfortunately, 3.5 GPF (13.2 LPF) parts often fit the new 1.0 GPF (3.78 LPF) flush valves.
- Sensor-activated flush mechanisms often result in more frequent urinal flushing than manual flush valves. There is no evidence the sensors valves save water.
- Non-water urinals are considered compliant by most, but not all plumbing code authorities. The Uniform Plumbing Code and the International Plumbing code allow the urinals, but some local cities and counties have not yet approved the devices. It is wise to contact the local plumbing jurisdiction before installing non-water urinals.
The Energy Policy Act of 1995 set maximum showerhead flow rates rate at 2.5 gallons per minute (GPM) (9.46 LPM). Despite this federal mandate, some showers flows can still be found flowing in excess of 5 GPM (18.92 LPM). In addition, some ‘luxury’ hotels have subverted the law by installing multiple showerheads in guestroom shower stalls. Replacing excessive flow showerheads and removing multiple showerheads are some of the most cost effective retrofits inside hotels.
New, well-designed 2.5 GPM (9.46 LPM) showerheads offer a satisfying and effective shower experience for hotel guests. There are some models of showerheads that flow less than 2.5 GPM (9.46 LPM) and also have high levels of consumer satisfaction, but these are not recommended for safety concerns. As showerhead flow rates have decreased, the incidents of accidental scalding have increased; caused by the loss of thermal buffering in water volume when supply water temperature changes suddenly. Thermostatic mixing valves prevent this problem, and are now required by most plumbing codes. To date, thermostatic mixing valves are only tested and certified for flows of 2.5 GPM (9.46 LPM) or greater. Installing showerheads with flow rates below 2.5 GPM (9.46) is not recommended until thermostatic mixing valve requirements are amended to lower flows.
Water savings projections can be easily estimated by measuring the flow rates of the pre-existing showerheads, determining average hotel occupancy levels (assuming one 11-minute shower/guest/day), and calculating the water use differential.
Hotel managers are very sensitive to guest satisfaction ratings, and shower quality seem to evoke many guest reactions. It is very important to choose replacement showerheads that are known to have a high level of user satisfaction. Most high quality showerheads cost $5 to $12 in bulk quantities. We do not recommend using price as sole criteria when selecting showerheads for hotels
Flow rates for wash basin faucets in lavatories can reasonably be reduced to 0.5 GPM (1.89 LPM) or lower. (The current national standard and the major model plumbing codes in the U.S. call for a maximum flow rate in non-residential lavatory faucet installations of 0.5-gpm (1.89-lpm).) Projected savings are usually based on usage frequencies similar to toilet and urinal use. Flow durations are often estimated to be 5 to 30 seconds per use. Retrofitting aerators on the faucets is the most common and least expensive strategy. The water savings are small when compared to replacing toilets, but the cost of retrofit is minor, usually less than $1.00 per faucet.
Some wash basins are fitted with mechanical metering valves (automatically shut-off after a preset time span) or negative shut-off valves (user must continue to exert pressure on valve handle to maintain water flow). These types of valves are required to save water and deter flooding the lavatories. The metering valves are often adjustable for the duration of the flow. The flow should not exceed 5 seconds per activation.
There is no scientific evidence that sensor-activated faucets save water. To the contrary, recent studies have provided valid evidence that sensor faucets use much greater water than manually activated valves. Sensor activated valves provide user convenience, but are now known to be wasters of water.
Many hotels have landscaping surrounding the facilities, some even have attached golf courses. Where local climate demands regular irrigation, there are often vast opportunities for water savings from improving irrigation systems and practices. Water efficiency measures often achieve water savings of 30% to 50% of all irrigation water.
Many hotels include restaurants, bars, nightclubs, banquet services and room service; and this presents excellent opportunities to conserve water in the areas of food preperation and dish washing.
Food is often heated in steamers using a central boiler; connectionless steamers are alternative equipment that saves thousands of gallons of water per year.
Asian restaurants use wok ranges extensively in food preparation. Traditionally, the intense heat of these wok ranges required a constant flow of water to cool the equipment. Waterless woks are now available, eliminating most of the water use.
Pre-rinse spray valves, using 4 GPM ( 15.1 LPM) are used to rinse dishes before placed in the dishwasher; new efficient spray valves use only 1.2 GPM (4.5 LPM) and save hundreds of gallons per day (depending on volume and type of meals served).
Ice machines are commonly found in food and bar service facilities; and this equipment can use surprisingly excessive amounts of water. Depending on the model and the settings, ice machines use 2 to 18 pounds (.91 kg to 8.2 kg) of water for every pound of ice produced.
The water efficiency of commercial dishwashers also varies greatly. The high cost of these machines often impairs the benefit-cost ratio of early replacement; but as older dishwashers fail, high efficiency models should be installed as replacements.
Most hotels employ the use of a cooling tower in the HVAC system to cool the buildings. Cooling towers use the cooling effect of evaporating water to remove heat from water circulating through the HVAC chillers. There are numerous ways for the system to waste water when the system is not properly maintained. Depending on the climate zone and the cooling system, the water wasted can be greater than all the sanitary fixtures combined. Appropriate retrofits usually require a conductivity controller and a pH controller be installed and properly maintained to achieve water efficiency. Conductivity controller retrofits, usually cost less than $1,500 for an average sized cooling tower, and can save more than $800 per year for a typical office or classroom building.
There are ample technologies available to greatly improve the water efficiencies of most cooling tower systems. Technology provides the tools for water savings, but does not guarantee water efficiency. Controller installations and retrofits must be part of an overall customer maintenance and education program to be effective.
Where the local wastewater treatment agency provides reclaimed water (wastewater treated to drinking water standards, though deemed non-potable), hotels provide an opportunity to supplant potable water use with reclaimed water use. Landscape irrigation is the most obvious opportunity to use this water. Reclaimed water can also be used to supply water to toilets and urinals. Depending on the water quality requirements, many cooling towers can also use reclaimed water rather than potable water.
In all applications, the reclaimed water must be strictly separated from potable water sources and end-uses. This requires a clear separation of pipes supplying water to the end use (irrigation system, toilets, urinals, cooling tower, etc) from pipes supplying potable water to faucets, drinking fountains, etc. Irrigation systems are usually on separate meters and water supplies; thus, this is the most common application for reclaimed water use.
In existing buildings, the water supply pipes for toilets and urinals are often interconnected with faucets and drinking water fountains; requiring extensive plumbing system retrofits if reclaimed water is to be used. Retrofitting a pre-existing plumbing system inside a hotel is usually too costly to justify the use of reclaimed water to flush sanitary fixtures. When constructing new buildings, the cost to separate the water supply pipes for sanitary fixtures is marginal. Many water agencies are now requiring new public buildings be designed with dual plumbing to separate the plumbing so reclaimed water can be used to flush sanitary fixtures, even if reclaimed water is not immediately available. Plumbing contractors this has ads less than 15% to the total cost of the plumbing system.
Storm Water Collection and Use
Collecting the rainwater on the building site (roof, parking lot, hardscape, landscape, etc.) is one of the fastest growing strategies in the water conservation industry and the “green” building efforts. There are three distinct advantages to storm water collection and use:
- The collected water can be stored then used to irrigate the landscape during dryer months.
- The water collected is prevented from entering the storm water system, which is often overtaxed in urban areas causing flash floods.
- The pollutants from the building site (fertilizers, herbicides, pesticides, animal waste, automobile fluids, etc) are prevented from being carried by storm water to streams, rivers, and other aquatic ecosystems. These pollutants are classified as ‘non-source point pollution’, and recent studies have shown the profound negative effect on local water quality.
Most hotels have in-house laundry facilities to clean bed clothes and towels used by guests. The water used to launder these items is a significant portion of the hotel water use. Each set of bed sheets requires 6 to 8 gallons of water to launder; a towel set (bath, hand and face) requires an additional 6 to 8 gallons (22.7 L to 30.2 L). The most effective means to reduce water use for laundry is to encourage guests to re-use the sheets and towels during their stay. As a comparison of strategies: improving the water efficiency of the on-premises washers may costs thousands of dollars and will likely yield water savings of no more than 25%; guests re-using each towel and sheet set twice before laundering will yield water savings of 50% at a very minimal cost. Hotel towel and sheet reuse programs requires a cooperative effort from both the guests and the hotel staff. The program usually includes the following components:
- Promotion tent cards are placed in rooms and/or bathrooms to inform guests of:
- The precious value of water
- The need to conserve water
- Asking for guest assistance in re-using towels and sheets before laundering
- The procedures to reuse towels (hanging on towel rack usually indicates laundering not necessary)
- The procedures to reuse bed sheets (only upon guest request to housekeeping)
- Guests participate by following the instructions on the card
- Staff only removes and replaces towels and sheets as guest indicates
There are several key elements that must be adhered for this strategy to work effectively. The promotion tent cards must be readily visible for the guests to notice and read. The appeal to the guest must be effective; guests have little motivation to save money for hotel owners. The staff must also cooperate and follow the wishes of the guest; it is not uncommon to have housekeeping staff remove and replace towels even when the guests hang the towels on the rack indicating they do not need laundering.
Program effectiveness can be projected using the following formula:
Q = R x Oc x L x W x P
Where: Q = the Quantity of water saved
R = quantity of guest Rooms
Oc = average Occupancy percentage of the hotel
L = average Laundry per room, towels and sheets, measured in pounds
W = Water used per pound of laundry (water efficiency of washer)
P = Participation rate by guests and staff (percentage)
Water Savings Example:
200 (rooms) x 75% (occupancy rate) x 5 (lbs/room) x 7 (gal/lb fabric) x 60% participation
Water savings projection = 3,150 gallons per day; more than 1,000,000 gallons/year
(11.9 m3 per day; more than 3,785 m3 per year)
The most common mistake made by hotel management is not providing adequate towel rack space for the towels to hang and dry between uses. When guests are forced to hang the towels squished together, the guests find the towels are still damp (and possibly musty) the next day. Many hotel guestrooms were not designed to provide towel drying space because the hotel policy was to wash the towels everyday. Hotel managers are strongly encouraged to add extra towel racks in the rooms (if necessary) before implementing this program.
Additional information to improve the efficiency of the on-premises laundry facilities at hotels can be here.
Some motels provide coin-operated clothes washers in common areas for guest use, and this provides a significant water saving opportunity. Most coin-op washers have a Water Factor rating of 12 to 14; using 35 to 45 gallons per load (132.5 L to 170.3 L). Newer water efficient models have a Water Factor rating of 4 to 8; using as little as 15 gallons per load (56.8 L). Water savings projections require frequency of use estimates, and this is difficult data to obtain unless the business manager regularly records accurate “coin counts”. These machines are often owned by vendors known as ‘route operators’, where the hotel owner receives a portion of the machines’ gross revenues. Any effort to replace the machines with more efficient models requires the cooperation of the route operator.
Additional information on common area laundry efficiency can be found here.
Hardscapes (sidewalks, decks, walkways, etc) are often sprayed with water from a hose and nozzle as part of a cleaning regimen, especially of food service facilities and patio dining areas. While dry sweeping the surfaces with a broom is preferred, health and sanitation objectives require the food be rinsed off the hardscape with water. The traditional hose and nozzle uses more than 5 gallons per minute (18.92 LPM), while waterbrooms use less than 1 gallon per minute. Water brooms use an array of high velocity, low water volume nozzles to scour the surfaces. The majority of users also attest the waterbroom cleans the surfaces faster and cleaner than the traditional hose nozzle method.
Additional information on waterbrooms can be found here.