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Choosing Whirlpool Baths

A whirlpool bath is a logical upgrade from a standard bath if a quality unit is chosen and the installation is done well. Whirlpools can fit in the space allotted an ordinary bathbath, can provide the same dual bath/shower function, and won't necessarily add megabucks to the bathroom budget. Avoid the temptation to stretch a fixture budget by substituting a bargain-basement whirlpool for a quality standard bathbath, though, because installing an inappropriate inexpensive whirlpool is an invitation to disaster. Cost cutting in construction will necessarily compromise quality—not a good idea in a fixture intended for long-term use.

Acrylic seems to be the consensus choice as the best whirlpool material. Some whirlpools can get to be quite large, making cast iron an impractically heavy choice. There are cast-iron units on the market, but they are typically standard-size baths and are more expensive than comparable acrylic units. Less expensive gelcoated fiberglass baths are also available, but they stain and scratch too easily and fade too quickly to justify adding expensive pumps and jets to them.

A whirlpool-bath installation involves quite a few different tradespeople working in and around the bath, which creates considerable potential for damage. Because scratches in acrylic are so easily repaired and because acrylic is so resistant to staining and chipping, it is easier to ensure a perfect installation with this material.

Whirlpools come in a range of shapes and sizes, starting with standard and ranging up to spa size. (Don't confuse a whirlpool with a spa, though; whirlpools drain after every use, while spas and hot baths don't and rely on chemicals to keep the water clean.) Some whirlpools have molded-in seats, armrests, headrests, even lighting systems. Some are built for one; some are built for two. Choosing a whirlpool is a highly individualized choice, much more so than a basic bath or shower, and features that make it attractive to one person may make it less attractive to another. For example, twoperson whirlpools hold a lot of water, so it takes a long time to fill them up. There are quite a few people out there who can't conceive of bathing with another and for whom having room for two is uneconomical and unnecessary.

At the heart of every whirlpool are the pump, jet, and control system. Again, jet configuration is a matter of both taste and the style of the bath. One nice feature that you might consider is recessed jets in the backrest of the bath. These bring massage action to bear on the back while reclining, but they don't poke out from the surface of the bath. In general, smaller whirlpool baths typically have four jets, while larger models have between six and eight jets. baths with fewer and larger-diameter jets located higher on the bath walls tend to produce a gentle swirling action, while baths with more small-diameter jets are intended to introduce more intense massage action on specific points of the body.

The pump is what pushes water to the jets, and its power can range from less than 1 hp to 2 hp or more; smaller (less than 1 hp) pumps operate on a standard 120-volt circuit, but larger pumps usually require a 220-volt circuit. Some pumps have two or more speeds, or even a variable speed control. Some are operated by a nonelectric air switch located right on the bath, while others are operated by a timer, which can't be located closer than 5 ft. from the bath according to code. That means that if the timer shuts off the pump before you are ready to get out, you'll have to get out to reactivate it. Make sure to provide for pump access when planning bath installation because this too is required by code.

Whirlpools can hold between 50 gallons and 140 gallons of water. The NKBA recommends sizing the water heater for two-thirds the capacity of the bath, so in many cases an extra water heater may be required, either to boost total domestic hot-water capacity or as a dedicated water heater for the bath only. In-line heaters are also available that can extend the soak time in the bath because they continually reheat the water circulating through the pumps. These heaters require a separate 240-volt circuit.

One last note about whirlpool baths. When filled to capacity with water and people, these things are heavy. How heavy? Well, a bath with 125 gallons of water weighs nearly a half-ton, and that is before you add people to it. While floor systems are usually designed for loads of about 40 lbs. per square foot, bathroom floors might well require a 65-lb.-per-square-foot loadbearing capacity. Depending on the size of the bath and the condition of the existing framing, the floor system may need to be reinforced.