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Preparing a basement room for an indoor pool

I am looking for advice on preparing an unfinished basement room for the installation of an Endless Pool (www.endlesspools.com). Specifically, I need advice on insulation recommendations and moisture barrier (if any). House is located in Northern Virginia, USA.
I’ve read that the old practice of insulating a basement room is to put up fiberglass batt insulation with a vapor barrier. This method can create mold issues as the vapor barrier can trap moisture between the foundation wall and the moisture barrier.
The newer and preferred method (“Insulate and Weatherize” Bruce Harley Taunton Press) is to put up rigid polystyrene insulation directly against the basement wall. Build a 2x4 wall against the polystyrene. Unfaced fiberglass batt insulation can then be placed in the stud bays if desired.
Is the polystyrene method applicable for a pool room? What about using spray foam insulation? Are there additional considerations for the ceiling since the space above is ‘living’ space (the sun room)?

Below is the description of the room and all applicable details I could think of. The attached picture is of the future pool room. The large metal rectangle in the middle of the room is the walls of the pool. (Please ignore the various materials in the foreground.)

Any assistance is greatly appreciated. Thanks in advance.

Future pool room rough description:
- Unfinished basement area
- Room is at/above grade level
- Three walls are exterior
- Walls are poured concrete
- Space above the pool room is the sun room
Pool room finish plans:
- Floor: tile
- Walls: tile 2/3 up wall backed by cement board, upper 1/3 will be paperless drywall
- Ceiling: paperless drywall
Pool description:
- 8’x14’ above ground lap pool
Moisture considerations:
- When pool cover is in place manufacturer states there is 0 moisture loss
- Rough in for ventilation fan in place
- Room dehumidifier with ventilation fan will handle moisture loss when pool is in use

Timothy Miller
Re: Preparing a basement room for an indoor pool

Howdy how are you going to deal with the added moisture into the rest of the house?
Depending on what part of the country you are in moisture is more or less of an issue. Last basement pool system i saw was fiberglass steel studs 6 mill plastic They went the extra step ov caulking all the studs to plastic so screws did not breach the water proofing. They installed a timer for exhaust fan vented outside to expell the moisture.

Re: Preparing a basement room for an Endless Pool

Hi Drew, you can visit this section of our website for a short video on humidity and how to mitigate it: http://www.endlesspools.com/plan/plan_humidity.html

Re: Preparing a basement room for an indoor pool

In your case I would really really consider forfeiting the whole drywall, framing, insulation system and go for a basement finishing system.

But not only that... I'd pick a 100% waterproof, mold resistant,insulated, cement board core based basement finishing system. The kind that won't get ruined or absorb moisture even if you dunk it into a pool.

Those systems are all in one solutions. They give you moisture and thermal protection along with a finished look.

The cement core gives you usable weight bearing walls, you can hang flat screen TVs, books shelves, no need to look for studs and panels can be removed as needed to access wiring and plumbing, inspect the concrete walls for cracks etc...

A basement, which is already a humid cave-like structure, would not be my first pick for an indoor pool, but if I had to do it, I'd take every possible precaution to make sure the finishes are as waterproof as possible.

Re: Preparing a basement room for an indoor pool

I hope i am not too late to the discussion... Proceed with GREAT caution! The potential for damage to your home is significant and $$$ if not done properly.

If you still would like to proceed...

Please seek experienced professional advice for your specific situation. The design and detailing of your wall and ceiling assemblies and thier interfaces are critical for an indoor pool room. Consideration must be given to the transport of moisture via moiture laden air flow and vapor diffusion to reduce the risk of condesationinto in the walls, ceiling, and adjacent spaces. Condensation brings with it words like MOLD, MILDEW, ROT, and the potential for significant damage to your home. This is one of the few cases in this area where a class I vapor diffusion retarder (vapor barrier) is warranted...

Wouldn't you like to swim outside?

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