If you’re looking for a relaxing spa experience without having to leave your home, a soaking tub may do the trick. Admit it: Just the mere mention of this luxurious fixture lifts your spirits and takes your idea of ordinary bathing to extraordinary heights. So what separates this fancy-sounding fixture from a standard tub—or even its upscale cousin, the Jacuzzi? And how much will installing this opulent oasis in your master bath—or even your garden—set you back? The answers and more, ahead.

Deeper than the average bathtub, soaking tubs are designed to offer the ultimate in relaxation by allowing you to fully submerge. Just how far can you sink? Soaking tubs average 23 inches in height, while a standard tub typically comes in at under 19 inches. Some soakers can hold as many as 250 gallons of water, while the average bathtub holds between 25 and 45 gallons.

Photo by AT6 Architecture: Design Build

Dorothy Willetts, an interior designer based in Coachella, CA, notes that the distance from the bottom of the tub to the overflow drain (the additional drain on the side of the tub that prevents the tub from overflowing) is usually 18 inches or greater. Japanese soaking tubs have water depths of more than 22 inches.

Some soaking tubs have claw feet, while others rest directly on the floor. They can be free-standing, placed against a wall, or sunken. When it comes to size, soaking tubs blow regular tubs out of the water, with some topping out at 90 inches in length and 76 inches in width—big enough to accommodate two bathers.

Photo by The Refined Group

Aside from the overall aesthetic appeal, soaking tubs offer a therapeutic experience and a unique opportunity to unwind in total luxury.

“Soaking tubs can be a great benefit to a bathroom if the homeowner enjoys a bath,” says Willetts. “Relaxing in water is a great way to relieve stress.”

While the most common place to install a soaking tub is a big master bathroom, homeowners who live in mild climates choose to put them outside as well.

The biggest challenge homeowners face when installing a soaking tub is finding space for it. Renovating your master bathroom from the ground up will make it easy to include a soaking tub in the layout, but fitting one into a finished bathroom will be tricky.

However, Willetts says, most soaking tubs can fit into the space meant for bathtubs as they can be selected in a standard bathtub length of 60 inches. But because it’s a soaking tub, it will just be taller.

“Check with your designer, contractor, or plumber to make sure you have the room for the tub and either a wall-mounted or floor-mounted tub filler,” Willetts says.

Filling a soaking tub also requires more water than a standard bathtub, so that’s something to consider if you live in an area prone to droughts.

Additionally, if you have any physical limitations, climbing in and out of a soaking tub can be a challenge. Keeping a step stool or bench nearby can help.

You may be thinking, “I can soak just fine in a regular old bathtub.” You’re not wrong, but chances are it won’t be nearly as luxurious. Soaking tubs also lack the bubbles of a Jacuzzi—but that means you’ll be able to slip into a calm head space in a quiet environment.

Willetts says soaking tubs can range in price between $1,000 and $5,000 depending on the size and materials.

“A basic acrylic tub can run less than $1,000,” Willetts says. “Some tubs are made in a solid-surface material—much like quartz or even cast iron—and can be several thousand dollars.”

Liz Alterman is a writer who's covered a variety of subjects, ranging from personal finance issues for CNBC.com to career advice for The Muse. She is also the author of a young adult thriller, "He'll Be Waiting." Follow her on Twitter @LizAlterman.

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