Simply slope the floor a little around the drain to keep the water in the area. However, be prepared to shell out at least $500 to $700 more for this feature in addition to your walk-in shower costs.

I have bad knees and previously only had a walk-in shower, so having this tub has ... keeping clean as the water drains. It fills up in about seven or eight minutes and drains in about five.

Need a walk-in tub installed in Seattle, Washington? Our top picks include Independent Home, American Standard Walk-in Baths and DaBella.