Whirlpool bathtubs -- using water jets, air jets or both -- have become increasingly common in homes because they can relieve stress and tired muscles. In some instances they are custom-made or even retrofitted in an existing tub, but most often they are purchased pre-built and installed. If you are replacing a standard tub with a whirlpool tub, there are some physical considerations beyond whether it will fit in the old tub's space, whether the floor can handle the weight and whether your water heater can produce enough hot water to fill the whirlpool bath. You also need to consider where you'll put the pump that powers the jets -- sometimes the pump can be placed as much as 5 feet away, sometimes not, but Better Homes and Gardens magazine notes that you'll want it where it can be serviced without too much trouble. You also may want a dedicated heater for the tub if you are expecting to take prolonged soaks. And you need heavy-duty electric wiring that will accommodate all this stuff -- 15 amps for some tubs, 20 for others.
Water jets are more common than air jets and will give you a more vigorous massage, but the downside to them, according to HomeDepot.com, is that some water will remain in them after you're done, so there is a possibility that mold or bacteria can grow if the jets aren't cleaned regularly. (Water jets should be flushed about every other week. Along with possible periodic repairs of pumps and other mechanical and electrical parts, this is the main difference in maintenance of a whirlpool tub compared with a conventional bathtub). It's also not a good idea to use bath salts or oils if you have water jets, experts say. In a report available free online, ConsumerReports.org says the air jets can be noisier, lose heat quicker and are more prone to splashing. Whirlpool tubs that use both types of jets are less common but can give you a more varied massage; you can use both types simultaneously or separately. But it will be more expensive to buy and to operate, and you'll need two electric hookups. Running the pump isn't the entire cost of operation -- you also need to consider that you'll need about 50 gallons of warm water to fill some of these whirlpool tubs, which means increased use of the home's water heater. Underfilling whirlpool tubs can damage the pump -- some have sensors to shut off the jets if the water level is too low.
A very detailed report available on ConsumerReports.org says you can spend from $650 to more than $5,000 for a bathroom whirlpool tub, but that price is not always an indication of better quality. Editors note, for example, that a $650 Kohler whirlpool tub is just as satisfying as the most expensive tub it tested. Most major tub manufacturers like Kohler and American Standard now also offer whirlpool tubs. Jacuzzi is a big name in the whirlpool market, and its products are characterized by many soft jets rather than a few very powerful ones.
As with standard tubs, whirlpool tubs are available in a variety of shapes, sizes and materials. They can be built-in or freestanding. Unlike spas and hot tubs, the bathwater is emptied after each use.
There are some basic safety tips to keep in mind while using a whirlpool tub. Stay in too long and you could overheat -- a particular risk for people with high blood pressure or cardiovascular problems. Check with your physician for advice. Some hot tubs come with non-slip bottoms and hand grips. Remember that while the pumps are working, you are in agitated water that may make slipping a problem if you stand up. Some tubs have a mechanism called "spin-free" that will stop the pump if hair becomes entangled in the intake ports. As with standard tubs, it's a good idea to sit in one at the showroom to see how the contours fit your back -- a whirlpool tub that's comfortable for others may not be the optimal choice for you. The tub kit may include a timer, and there may be local code requirements that will require installation to be a certain distance from the tub to reduce the risk of an electric shock, Better Homes and Gardens advises.