Replacing a bathtub looks like a sequence of eleven steps until the tub comes out. Then it becomes a different project, because you can finally see what has been sitting underneath it for twenty years.
This guide covers the whole job: how to get the old tub out depending on what it is made of, the safety issue nobody mentions when the tub is cast iron, what to do about the soft subfloor you are quite likely to find, and how to fit the new one. It is written to be useful whether you are doing it yourself or deciding whether to.
Before you start: the tub material decides everything
Almost every guide describes one removal procedure. There are really three, and which one you are doing depends entirely on what the tub is made of.
| Material | Weight | How it comes out | The job |
|---|---|---|---|
| Acrylic or fiberglass | 60 to 120 lb | Carried out whole, or cut up with a reciprocating saw | Two to four hours |
| Enamelled steel | 70 to 110 lb | Two people carry it out intact | Half a day |
| Cast iron | 300 to 500 lb | Usually broken up in place | A full day, and it is demolition |
Not sure which you have? Tap the side wall with a knuckle. A dull, dense thud with no give is cast iron. A tinny ring is enamelled steel. Noticeable flex under hand pressure is acrylic or fiberglass. A fridge magnet held to the outside will stick to both metals and fall off plastic.
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How to Get Your Old Tub Out
Removing an acrylic tub and removing a cast iron one are not the same job. Three questions and you will know which one you have on your hands.
If your tub is cast iron, read this before you pick up a sledgehammer
The standard way to remove a cast iron tub is to cover it with a blanket and break it up in place. It is what the trade does, and it is the right method. As one plumber puts it:
"Cover it with a blanket or painters tarp and grab your sledgehammer. It will break, but you need to hit it really good. It's not a pretty [job]."
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What that advice usually leaves out is lead.
The porcelain enamel glaze on older tubs can contain it, and breaking a tub up turns that glaze into dust. Testing of porcelain-enamelled bathtubs has found roughly 62 percent positive for leachable lead overall, including about 77 percent of cast iron tubs and about 25 percent of steel ones, with glaze lead content reported as high as 88 percent. Demolition activities such as breaking or crushing can release that lead, and dust from porcelain enamel products is recognised as a potential lead dust hazard when disturbed during maintenance, remodelling or demolition.
The risk is not uniform. Where the glaze is still glossy and intact it is lower; where it has worn dull or gone chalky it is highest. Plenty of tubs are fine. But 77 percent of cast iron tubs testing positive is high enough that this belongs in any guide telling you to break one.
What to do about it:
- Test before you break. Lead test swabs are inexpensive and available at hardware shops. Swab the glaze, especially any worn or chipped area.
- If lead is present, or you cannot rule it out, get a quote for removal by someone trained in lead-safe work practices. In some jurisdictions that is not optional.
- If you proceed yourself: keep children and pregnant people out of the house for the duration, seal the doorway with plastic sheeting, mist the surface with water to suppress dust, wear respiratory protection actually rated for particulates rather than a loose surgical mask, and clean up wet with disposable cloths rather than sweeping or vacuuming with a domestic vacuum.
- Check your local rules, and treat EPA lead-safe renovation guidance as the authority here rather than this page.
An intact tub carried out whole creates no dust, which is worth remembering: if you can get it out in one piece, the question does not arise.
Common questions before you begin
How long does it take to remove a bathtub?
Between three or four hours and a full day, depending on the material and the layout. Acrylic is the quick end. Cast iron is the slow end and should be planned as a whole day rather than an afternoon.
What tools do I need?
Start with protection: eye protection, heavy gloves, and respiratory protection rated for dust if you will be breaking, cutting or grinding anything. Then:
- An adjustable wrench
- An assortment of pry bars
- Screwdrivers of varying sizes
- Slip-joint and channel-lock pliers
- Hammer and socket wrench
- Keyhole saw or utility knife
- Dust sheeting to protect the route out
- For cast iron: a sledgehammer, a cold chisel, a heavy blanket or tarp, and steel toe boots
- For cutting acrylic or steel: a reciprocating saw or angle grinder
Do I need to hire a professional?
Some of this is genuinely DIY and some of it is not, and the honest answer depends on three things: the tub material, what you find underneath, and whether the plumbing needs to move. Removing an acrylic tub and fitting a like-for-like replacement into an existing alcove is a reasonable weekend job. Breaking up a cast iron tub that may contain lead, or discovering rotted framing, is not. Our guide to bathtub installation costs covers what the labour runs to if you decide to hand it over.
How much does it cost to remove an old tub?
Removal alone typically starts around $300 and rises with weight, access and disposal. Cast iron costs more because it takes longer and produces several hundred pounds of material to get rid of. The full cost of replacing a bathtub has the complete picture.
How to remove an old bathtub in 11 steps
Bathtub removal is not complicated, but it happens next to water and electricity, so preparation matters more than speed. Work through these in order.
1. Prep the area
Shut off the water and the power to the bathroom. Remove obstructions: the toilet and vanity if the room is tight. Lay sheeting along the route the tub will travel. Budget real time for this, up to a few hours in a complicated bathroom.
2. Remove the drain, faucet and attachments
Disconnect the drain assembly and the overflow, then the faucet and any spout. Old drain assemblies seize; penetrating oil and a drain key earn their place here. See our guides to removing a bathtub drain and the bathtub overflow drain.
3. Separate the tub from the wall
Cut the caulk line and remove enough of the surround to expose the tub flange and the fixings holding it to the studs. If you are keeping the tiled walls, an oscillating multi-tool gives the cleanest cut at the tile line.
4. Remove and dispose of the old tub
Method depends on material, as above. On disposal: enamelled steel and cast iron are both scrap metal, and most scrap yards will take them, often paying for cast iron. Acrylic and fiberglass go out as general construction waste, and cutting them down first makes that far easier.
5. Stop and look at what is underneath
This step is not in most guides and it is the one that matters most. With the tub out you can see the subfloor and the bottom of the wall framing for the first time in decades. Check both before you do anything else. The next section covers what to do with what you find.
6. Choose the correct replacement tub
Measure the opening rather than the old tub, and confirm the drain hand, left or right, against your rough-in. Our guide to standard bathtub dimensions has the sizes and drain sizing covers the connection.
7. Protect the new tub during the move
Keep it boxed as long as possible, and leave the protective film on until the surround is finished. Most damage to new tubs happens during installation rather than delivery.
8. Install a new stringer
The stringer is the horizontal support fixed to the studs that carries the tub's rim edge. Set it from the new tub's specification, not the old tub's position, and check it level along its length.
9. Fit the drain and overflow
Fit the drain assembly and overflow to the tub before you set it in place. Doing it afterwards, from underneath, in an alcove, is the kind of job people remember. Installing a bathtub drain covers the sequence.
10. Set the tub and test it
Set it in a mortar bed unless the manufacturer says otherwise; for anything lighter than cast iron this is what stops the base flexing, and flexing is what eventually cracks the joint at the drain. Connect the plumbing, then fill the tub and let it stand before you close anything up. A leak found now is an inconvenience; found after tiling it is a demolition.
11. Check your work, then finish the walls
Verify level in both directions, confirm the drain runs freely, and only then reinstate the surround, backer board and tile. Caulk last, once everything is dry.
What you find under the tub
The most common turn this project takes is discovering that the subfloor under or behind the tub is not sound. It is the single most frequent subject in homeowner discussions about tub replacement, and the tell often appears before the tub comes out. One homeowner describes finding it during routine maintenance:
"I was recaulking my 2nd floor bath tub when I noticed some of the tiles were real loose."
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Another describes the version you notice from inside the tub:
"The tub is off level and seems to sink down half an inch in this rotted area."
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How to check it properly: push a screwdriver into any dark or discoloured area. Wood that resists is stained but structurally fine. Wood that sinks under light pressure is rotted and needs cutting out. Wood the screwdriver goes straight through, or joists that are dark and damp on top, is a different conversation entirely.
Do not install the new tub over compromised framing. It is the one mistake in this project that is genuinely expensive to undo, because fixing it later means taking the new tub out again. And whatever you find, photograph it before you cover it: it is evidence for an insurer, a reference for anyone quoting, and a record for whoever owns the house next. Our guide to signs of water damage covers what to look for elsewhere in the room.
Interactive
What You Found Under the Tub
The tub is out and the floor underneath is not what you hoped. This is the most common turn a bathtub replacement takes. Three questions and you will know whether it is a patch, a sheet, or a phone call.
What a new bathtub costs
| Tub type | Typical price |
|---|---|
| Basic acrylic or fiberglass alcove | $200 to $700 |
| Enamelled steel alcove | $300 to $800 |
| Mid-range acrylic, including soaker depths | $700 to $1,400 |
| Cast iron alcove | $800 to $2,000 |
| Freestanding, stone resin or premium materials | $1,500 and up |
Tub-only figures carried forward from the earlier version of this guide and extended by material; not individually sourced. Treat as order of magnitude for 2026. Removal, disposal, any subfloor repair and installation all sit on top. Our page on refinishing costs is worth a look first if the existing tub is structurally sound and only the surface has gone, because refinishing is substantially cheaper than replacement and avoids this entire project.
Common mistakes when installing a new tub
- Ordering the wrong drain hand. Tubs are handed. A mirrored tub is a return, not an adjustment.
- Skipping the mortar bed. The base flexes, and flexing cracks the drain joint over time.
- Closing up before testing. Fill it and let it stand before a single tile goes back.
- Installing over damaged subfloor. Covered above, and the most expensive of these to undo.
- Measuring the old tub instead of the opening. The old one may have been wrong, or shimmed.
- No access to the trap. Build in a panel if there is any way to do so.
Frequently asked questions
Can I replace a bathtub myself?
An acrylic tub swapped like for like in an existing alcove is a realistic DIY job for a competent weekend. Cast iron removal, moving plumbing, or anything that turns up rotted framing is where it stops being one. The material and what you find underneath decide it, not your enthusiasm.
How do you remove a cast iron bathtub?
Usually by breaking it up in place under a heavy blanket with a sledgehammer and a cold chisel, because at 300 to 500 pounds it will not go through a doorway intact. Before you do: the enamel glaze on older tubs can contain lead, and breaking releases dust. Test the glaze, and if lead is present get it removed by someone trained in lead-safe practices.
Do old bathtubs contain lead?
Many do, in the glaze rather than the metal. Testing has found roughly 77 percent of cast iron tubs and 25 percent of steel tubs positive for leachable lead. Risk is lower where the glaze is glossy and intact and highest where it is worn or chalky. Carrying a tub out whole creates no dust; breaking one up does.
What do I do if the subfloor is rotted?
Cut back to solid wood and further than the damage appears, because rot travels further than it shows. A patch smaller than a dinner plate with sound joists is straightforward. Damage reaching past the tub footprint, or joists that are dark and damp, needs someone to look at it while the floor is open.
How long does it take to replace a bathtub?
Removal runs from a few hours to a full day depending on material. A straightforward like-for-like replacement is a weekend. Add days if the subfloor needs repair or the plumbing has to move.
Is it cheaper to refinish or replace a bathtub?
Refinishing is considerably cheaper and avoids the whole removal project, and it is the right answer when the tub is structurally sound and only the surface has failed. It is not the answer when the tub is cracked, leaking, or the wrong size for what you want.
Choosing the replacement with Badeloft
The hardest part of this project is behind the wall. The part you will actually look at for the next twenty years is the tub, and it is worth picking that before you start rather than after the old one is in the skip.
Our stone resin freestanding collection is built for replacements where the room is being opened up anyway, and our freestanding installation guide covers what changes when the new tub has no walls to sit against.