HVAC Contractor Says Hotel/Motel Industry's Indoor Pool IAQ Problems Are Increasing

Crumbling walls, mold infiltration into hotel interiors and unhealthy IAQ are just a few problems suspected in more than 70 percent of North American major hotel chain locations.

Indoor air quality (IAQ) problems in many North American hotel/motel indoor pool rooms are increasing at an alarming rate.

While this might sound strongly opinionated, it’s a fact according to HVAC mechanical contractor, John Mills, president of Concept Air Systems, Mississauga, Ontario, an IAQ expert who has performed extensive IAQ corrections on more than three dozen failing indoor pools—mostly owned, managed or franchised under the hotel/motel industry’s top 50 brands.

Hotel/motel indoor pools could be the next major category of IAQ problems and could be following the pattern of respiratory and other health-related problems associated with mold, mildew and fungus, according to Mills. Many North American public buildings have made the front pages of newspapers with sick building syndrome, such as St. Charles High School, St. Charles, Ill., which was shuttered for one year during mold clean-up. Mills thinks sick building syndrome in hotels/motels will be the next health concern according to what he’s seeing on-site at his clients’ hotel/motel locations.

“What surprises me is that local health inspectors haven’t jumped on the mold bandwagon because it’s really becoming a health issue everywhere else,” Mills said. “No hotel chain is exempt from this IAQ problem.”

While most HVAC contractors service an occasional indoor pool, the niche has turned into 50 percent of the business for Mills’ 18-year-old contracting/service company.

Whether it’s due to meager construction budgets or consulting engineers that lack indoor pool design fundamentals, Mills estimates more than 70 percent of the hotel/motel indoor pools in North America are either improperly designed or not operating properly. Interior architectural design accounts for about 60 percent of malfunctioning hotel/motel indoor pools, while improperly installed mechanical units are 30 percent to blame, followed by 10 percent poor housekeeping practices, estimates Mills.

If it’s a pool room design problem, retrofits that resolve the IAQ issues could cost upwards of hundreds of thousands of dollars in construction costs. Poorly operating equipment could cost anywhere from a service call charge to tens of thousands of dollars in equipment replacement.

The top three problems Mills sees on a reoccurring basis are: 1) no vapor barrier or one that is not sealed or installed properly; 2) conventional HVAC equipment instead of specially designed dehumidification equipment; and 3) poor air distribution design.

Proper design of all three disciplines is outlined in the standards handbook of the American Society of Heating, Refrigerating, Air Conditioning Engineers (ASHRAE).

The vapor barrier—a plastic sheet that hermetically envelopes the top, bottom and sides of the pool room—is critical in keeping the room dry of condensation. Mills sees this vital part missing in many engineers’ designs.

Even rooms with vapor barriers can suffer moisture infiltration. Many times a vapor barrier isn’t sealed properly during construction, doesn’t envelope the entire room, or has holes poked into it accidentally or unknowingly by installation trades people, according to Mills.

Mills recalls a major hotel chain site he recently consulted that had interior walls bowing inward and the exterior brickwork showed signs of deterioration due to interior wall moisture accumulations. “I knew immediately there was a vapor barrier problem; and that was without opening the wall to inspect it,” said Mills.

The worst hotel case Mills has seen to date was an indoor pool room with no vapor barrier at all. The three-year-old facility was already suffering from deteriorating structural block walls that were crumbling due to moisture infiltration and freeze/thaw cycles. Consequently, mold and other biological growths were rampant.

Another factor in poor indoor pool IAQ is the attempt to solve high humidity problems with conventional air conditioners or furnaces. The heavy humidity loads produced by a quick evaporating 84º F pool can only be surmounted by commercial dehumidifiers. Mills services all brands, but prefers the DRY-O-TRON™ models of Dectron Inc., Roswell, Ga., because they use an energy efficient heat recovery method to provide free pool water heating, while simultaneously removing excess moisture and cooling or heating the space.

Mills claims too many hotel owners and managers settle for the cheapest HVAC equipment that either don’t include dehumidification or dehumidify without providing energy savings in the long run. “They might put in some cosmetic touches like marble that offer a nice appearance, but the behind-the-scenes aspects such as providing proper environmental conditions that don’t deteriorate the building structure or make inhabitants sick, are often times neglected,” Mills added.

Besides equipment and structural flaws, air flow is often a cause of IAQ problems and condensation as well. The cheapest air distribution method is running ductwork down the middle of the pool room and hoping registers evenly distribute air. Proper air flow design however, should have a combination of under-deck ductwork for upward movement and overhead perimeter ductwork for downward air flow, especially in the critical case of windows.

Another problem associated with walls of windows and/or skylights is ribs that protrude three or more inches away from the glass and block air flow from broadcasting entirely across the glass.

Mills has learned the essentials of indoor pool environment analysis through experience, however most of the things he has suspected, such as the importance of room design principles have been confirmed in the HVAC industry’s only school for dehumidification hosted by Dectron. He regularly sends his service people to the two-day school held in Niagara Falls, N.Y.

“Most HVAC service people tend to only look at the mechanical equipment and they think I’m crazy for including the architectural design in the troubleshooting,” said Mills. “However, the school is great in explaining that failing to meet set point temperatures many times is not due to poorly operating mechanical equipment, but due to the inefficiencies of the pool room design.”

While Mills’ mission is mechanical contracting and service, he also offers indoor pool consulting services to hotel managers that include audits and recommendations of construction contractors and techniques required for remedying a problem.

Mills recommends many ideas for hotel/motel executives who want to avoid the oncoming health issues facing the indoor pool industry: 1) don’t use the least expensive dehumidifier, especially when a medium or higher-end model will pay for itself in heat recovery and free pool water heating; 2) make sure consulting engineers and architects work together when designing the indoor pool envelope in new construction; 3) check existing pool rooms for any kind of wall surface problems such as peeling paint, discolorations around utility connections, and/or visible mold on grout joints. These problems are usually indicators that larger problems exist in hidden spaces.

Generally, Mills thinks the hotel/motel industry should start preparing for the future by planning better pool rooms and reviewing the performance characteristics of existing sites. “Hotel executives aren’t going to realize the seriousness of this (health issues related to poor performing indoor pools) until more of these issues start going public,” he said.