Mildew and Rust Spoil Indoor Pool Room

House Doctor | Gary Dymski

July 19, 2001

Moisture-Plagued Pool Room

Q. I read a recent column ("Pooling Your Resources," June 28), and, unfortunately, my problem isn't with the color of my pool water but rather with the condition of the room for my indoor pool. I had an indoor pool installed in my home and left the details to the builder. For the first two years, the pool room looked very nice. Now, what a disaster.

First, the builder filed for bankruptcy and is out of the picture, so I'm on my own.

The builder used greenboard on the walls and covered them with an epoxy paint, installed baseboard heating (which is rusted), and installed two standard dehumidifiers (which the chlorine ate at and caused belts and motors to deteriorate). The wooden windows are mildew-stained, and the paint and spackling around the two skylights are falling apart. Because of the high moisture content of the room, the greenboard walls show mildew stains and won't hold drywall tape or spackling.

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In addition, there are problems with my ceiling fans, high-hat lighting and the ridge venting on the roof.

Do you have any inexpensive suggestions on how to redo this room other than tearing it down? The room is approximately 20 feet by 40 feet with a cathedral ceiling.

-M.J.P., Huntington

A. Sorry, but I don't have any inexpensive suggestions. It appears to me you're going to have to do quite a bit of work to get the room for your indoor pool in proper shape.

I doubt your builder was experienced in creating rooms for indoor pools. The chemicals and the humidity from your pool water are causing most of the problems, and it appears he did not install a ventilation system to change the air in the room. My first bit of advice is to consider having a ventilation system installed specifically for the pool room.

As for the walls, greenboard - a moisture-resistant type of drywall - will not stand up to the high humidity and temperature changes in this room. I'd suggest tearing out all the greenboard and replacing it with cement backerboard. Your most inexpensive alternative might be to then cover the cement backerboard with ceramic tile.

But before you start making too many changes, why not contact an architect or a contractor who specializes in indoor pool design and construction? Your indoor pool room contains building materials that can't stand up to moisture, chemicals and drastic temperature changes without some help. You have so much going on here - including electrical and heating - that you need to be thorough in your approach.

"We come across this problem pretty often," says John Tortorella, owner of J. Tortorella Swimming Pools in Southampton. "The pool installer does his job and the builder does his job, but no one ties them together."

Tortorella says Desert Aire Corp., a Milwaukee-based company that specializes in heating, ventilation and air-conditioning systems for indoor pools, is probably where you should begin.

At the very least, contact the National Spa & Pool Institute (www.nspi.org; 800-323-3996), a trade assocation based in Alexandria, Va. The institute can furnish you with information on building indoor pools as well as a list of indoor pool builders.