What is bathtub replacement?
Bathtub replacement removes an existing tub and installs a new one, with new plumbing connections and wall or floor repairs as needed. The tub you choose, whether an alcove tub, a freestanding tub, a deeper soaking tub or a tub-shower combination, determines how much of the bathroom has to change around it. The size and type of the space, the floor's strength and the plumbing layout matter as much as the tub. For how this fits into a larger project, see bathroom remodeling in Kirkland.
Alcove tubs
An alcove tub sits in a three-wall recess and is the standard tub in most homes. The usual size is about 60 inches long and 30 to 32 inches wide, which lets one replace another without moving walls or plumbing.
Materials
- Acrylic: lightweight, warm to the touch and available in many shapes. It is the most common choice for replacements.
- Fiberglass: the most economical option, though the surface can scratch and dull sooner than acrylic.
- Enameled steel: a durable, budget-friendly tub that is cold and can be loud when filling unless insulated.
- Cast iron: very durable and holds heat, but weighs several hundred pounds and needs a strong, well-supported floor.
Left, right and center drains
Alcove tubs come in left-hand and right-hand drain versions that must match the existing plumbing, so measure carefully. A mismatch means moving the drain.
Freestanding tubs
A freestanding tub stands on its own rather than in a recess, and it's often the centerpiece of a primary bathroom. It needs more room than an alcove tub and extra planning.
Space, filler and drain
Most freestanding tubs need clearance on all sides for cleaning and access. Faucets may be floor-mounted, wall-mounted or deck-mounted, and each requires its own rough-in, so the choice of filler has to be made before the floor and walls are closed up. The drain and overflow are typically in the floor, which can mean opening a subfloor if the new tub's drain doesn't line up.
Structural and floor considerations
Water weighs about 8.3 pounds per gallon, so a tub holding 60 gallons carries about 500 pounds of water, plus the tub and the person in it. Heavier tubs on upper floors call for a check of the floor framing. Some freestanding tubs also hold more hot water than a household water heater tank can supply at once.
Soaking tubs
A soaking tub is built for depth: the water level is higher than a standard tub, so you can sit with water up to your shoulders. Soaking tubs may be freestanding, built into a platform or installed as drop-ins.
What to check before choosing one
- the capacity in gallons, and whether the water heater can fill it with hot water
- the floor's load capacity, especially on upper floors
- whether the overflow, drain and filler fit the tub's depth
- how easy the tub is to step into, particularly for older users
- whether a deep tub makes sense if the household includes small children or older adults
Tub-shower combinations
A tub-shower combination, a tub with a showerhead above it and a surround on three walls, is the workhorse of most family bathrooms. It saves space and cost and serves everyone.
Surround choices
Surrounds can be a one-piece acrylic or fiberglass unit, a panel system or tile on a waterproofed substrate. Tile needs the same waterproofing as a shower. Our shower remodel page covers membranes and pans, and tub-to-shower conversion explains the option of replacing a combination with a walk-in shower instead.
Curtain, door or glass panel
Sliding doors, hinged glass and fixed panels keep water in more reliably than a curtain, though a curtain is the simplest and least expensive option.
Replacing versus refinishing
Refinishing recoats the surface of the existing tub, which can restore a worn finish at a lower cost than replacement. It doesn't fix cracks, a tub that is the wrong size, or a failing surround, and the new finish wears over time. Replacement is the better choice when you want a different shape or size, when the tub is damaged, or when the surrounding walls are being rebuilt anyway.
How a tub replacement works
Measure and choose
Measure the alcove, the drain location and the access path for carrying the tub in. Cast iron and large acrylic tubs can be difficult to move through narrow doors and stairs.
Remove the old tub and surround
The surround or wall surfaces are removed, then the tub is disconnected and taken out. This is when water damage behind the tub shows up.
Repair and rough-in
Subfloor or framing repairs are made, and the drain, overflow and valve are set for the new tub.
Set the tub
The tub is leveled and supported, often on mortar or foam to prevent flexing and noise.
Rebuild walls and finish
Walls are waterproofed and surfaced, and trim, fixtures and glass or curtain are installed.
What affects cost
The tub material and size, a freestanding versus alcove layout, filler type, surround choice (panel, acrylic or tile), plumbing changes and repair of hidden damage all move the price. See the bathroom remodel cost guide for how to compare estimates.
Tub replacement in Kirkland and nearby
In Kirkland, replacing a tub in the same location with no plumbing line changes may fall under the city's exemption for like-in-kind fixture replacement, but adding a freestanding tub, moving the drain or opening walls changes that. Lakeside homeowners should check the city's critical-area tool first. Condominium owners in Bothell and downtown Kirkland also need association approval and may have rules about floor loads and work hours. A local contractor can explain what applies to your property, and the overview of bathroom remodeling in Kirkland, WA shows where tubs fit in the wider picture.