Bathtub Buying Guide: Freestanding, Alcove, Drop-In & Undermount Explained

A bathtub is one of the most significant investments in a bathroom remodel — both in cost and in the experience it delivers. This guide covers every type, material, and consideration to help you choose the right tub for your space.

Bathtub Types

Freestanding Tubs

The statement piece of luxury bathrooms. Freestanding tubs sit independently on the floor, visible from all sides. They work best in larger bathrooms (minimum 5' x 8' for comfortable placement).

• Slipper tubs — One raised end for reclining. Classic and elegant.
• Double-ended — Both ends are raised. Centered drain allows two people to face each other.
• Pedestal — Sits on a solid base. Modern, clean lines.
• Clawfoot — Traditional look with exposed feet. Vintage charm.

Popular options: The KOHLER Abrazo, KOHLER Veil, and Kallista freestanding collections are among our best sellers.

Alcove Tubs

The most common type in American homes. Fits into a three-wall recess. Typically 60" long, available in 30"-36" widths. Often paired with a shower for a combination tub/shower setup.

Alcove tubs are the most affordable option and the simplest to install since they use a standard rough-in.

Drop-In Tubs

Dropped into a surrounding deck or platform. The rim sits on top of the deck surface. Allows for custom tile or stone surrounds. More installation work but maximum design flexibility.

Undermount Tubs

Mounted beneath the deck surface so the rim is hidden. Creates a clean, seamless look. The most premium installation type — the deck material (stone, tile) extends over the tub rim.

Bathtub Materials

Acrylic

The most popular material. Lightweight (easier to install on upper floors), warm to the touch, retains heat well, and available in the widest range of shapes. Most KOHLER and Delta tubs are acrylic.

Cast Iron

The classic choice. Extremely durable, retains heat longer than any other material, and has a porcelain-enameled surface that resists scratching. Heavy (300-500 lbs) — verify floor support. KOHLER's Bellwether and Villager are iconic cast iron tubs.

Engineered Stone / Solid Surface

Premium material with a natural stone appearance. Warm to touch, excellent heat retention. Used in luxury brands like Kallista and Victoria + Albert.

Fiberglass

The most affordable option. Lighter than acrylic but less durable. Best for budget renovations or rental properties.

Key Dimensions

• Standard alcove: 60" L x 30-32" W x 14-16" soaking depth
• Spacious alcove: 60" L x 36" W x 16-20" soaking depth
• Freestanding: 55-72" L, 27-36" W, 15-22" soaking depth
• Soaking depth matters: Measure from the overflow drain to the bottom. Deep soakers (18"+) cover your shoulders when reclined.

Hydrotherapy Options

• Soaking tub — No jets, just deep water. The simplest and most popular choice.
• Whirlpool / Jetted — Water jets for targeted muscle massage. KOHLER's water jets are powered by a pump system.
• Air bath — Thousands of tiny air bubbles for a gentle, all-over massage. Quieter than whirlpool jets. KOHLER BubbleMassage is the gold standard.
• Combination — Both water jets and air bath in one tub. The ultimate spa experience.

Installation Considerations

• Floor support: Cast iron tubs can weigh 500+ lbs filled with water and a person. Verify your floor joists can handle the load.
• Access: Measure all doorways and hallways. Freestanding tubs can be large — confirm you can get it into the bathroom.
• Drain location: Left-hand drain vs right-hand drain. Stand facing the tub — the drain side is the "hand."
• Overflow: Required by code. Prevents flooding if the tub overfills.

Our Recommendation

For a primary bathroom, an acrylic freestanding tub in the 60-67" range gives you the best balance of luxury feel, practical size, and value. For a tub/shower combo, a KOHLER or Delta alcove tub with an integrated apron front is the most reliable choice.

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