People think that they can invent inexpensive solutions to the issues that plague indoor swimming pools. And, I'm sorry to burst your bubble, but they have all been tried before and they have all failed.
Do not waste your time and money on "things that might work." The key to a healthy and safe indoor pool is dehumidification and controlling vapor transmission.
A vapor barrier exists to prevent the transmission of water vapor (microscopic droplets of water) into the building envelope. Once that occurs, many terrible things happen to the building and occupants:
corrosion of wiring
short circuit of electrical components
decay of building fasteners, brackets and structural elements
upper respiratory ailments
The main key to controlling the moisture in the air (humidity), is to remove it. While pool covers, temperature control and ventilation are important, together or by themselves they cannot mitigate the water vapor that will emit from the pool. Like gravity, it cannot be prevented or turned off.
However, once into the environment, the humidity can be controlled. Dehumidifiers dry the air and return the dried into the envelope. Provided the natatorium has a properly installed vapor barrier, the moisture ends there.
Mechanical Engineer and HVAC Contractor
You do not want to hire an mechanical engineer or HVAC contractor who is not experienced with indoor pools. Though there are many reference sources available for them, you do not want them learning or experimenting on your project.
This is as much as a science, as it is an art. Though dehumidification ducting and systems may be sized properly, installing the registers, returns or controls in the incorrect location will negate the efficiency of the entire system.
It's been done before
Because you don't want to spend the money on a dehumidification system, don't think that you have struck upon an alternative solution.
Every "bright idea" has been tried:
sliding doors and windows
moveable hydraulic floors
heated pool decks
The ONLY solutions to controlling the humidity in the room are a dehumidification system, building an outdoor pool or leaving the pool empty.
Experience can save you a bundle on the learning curve.
Paolo Benedetti, SWD, Principal
Aquatic Technology Pool and Spa
International Swimming Pool Consulting and Design, Aquatic Consulting, Watershape Consultants, Expert Witness, Hydraulic Design, Landscape Architecture, Construction Management
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