How to Price a Tub-to-Shower Conversion: Drain Code, Plumber Scope, and the Three System Choices That Change Your Pricing

By Cesare L., residential tile installer with 13 years of experience.

A homeowner calls. They want to convert their old alcove tub into a walk-in shower. "The space is already there, shouldn't be too complicated, right?"

You think about it: demo the tub, build a shower pan in the same footprint, tile the walls. Maybe 3-4 days of work. You quote $7,000 to be competitive.

Then reality hits during the job:

• The tub drain is 1.5 inches, but code requires 2 inches for shower drains — so the plumber has to replace the drain line, possibly cutting into the subfloor from below
• The cast iron tub weighs 350 pounds and you couldn't lift it alone — had to bring in help and nearly cracked the subfloor getting it out
• The dump fee for hauling the tub was $275 (you had it in at $50)
• The homeowner assumed your price included the new shower valve, but the plumber is quoting $800 separately and the homeowner is calling you about it
• The glass door fabricator can't measure until your tile work is completely done, adding 2-3 weeks to the project timeline you didn't account for

By the time you're finished, you've gone $2,800 over budget, had multiple awkward conversations about scope, and made $25/hour on what should have been a premium job.

Tub-to-shower conversions are one of the most misunderstood job types in residential tile contracting. The homeowner sees the same footprint and thinks "swap out the tub for a shower." The reality involves mandatory code upgrades, plumber coordination, demolition hazards, and system choices that dramatically change the scope of work.

This article is the framework I use for tub-to-shower conversion pricing. If you're quoting one in the next 30 days, read this first.

The Short Answer: Price Tub-to-Shower Conversions at $7,500–18,000 Depending on System Choice

The pricing tiers by system type:

• Acrylic shower pan + tile walls: $7,500–10,500 (plumber installs pan, you tile walls)
• Custom tile shower with curb (Kerdi/Wedi system): $10,000–14,000
• Custom curbless tile shower: $13,000–18,000+
• Premium custom with natural stone or specialty features: $15,000–25,000+

These numbers INCLUDE tile work but are EXCLUSIVE of the plumber's scope. Plumbing is always billed separately by the plumber directly to the homeowner. We'll get to why in a minute.

Key pricing principle: never bundle the plumber's work into your estimate. Your scope is tile work, waterproofing, substrate prep, and demo. The plumber's scope is drain relocation, valve replacement, and supply line modifications. Separate trades, separate invoices.

Why Every Tub-to-Shower Conversion Requires New Plumbing

This is the thing homeowners don't understand and installers don't explain clearly.

The drain code requirement

Building codes require shower drains to be 2 inches in diameter. Bathtub drains are 1.5 inches. When you convert a tub to a shower, the drain line has to be upgraded, period. This isn't optional. This isn't "if the code officer shows up." Every tub-to-shower conversion legally requires new drain line sizing.

What this means practically:

• The existing 1.5" drain line must be replaced with a 2" drain line from the new shower location all the way back to the next larger pipe it connects to (typically the main stack)
• Depending on the home's construction, this might require cutting into the subfloor from above OR accessing the plumbing from below (crawl space, basement, or drop ceiling)
• If the home is on a slab, the plumber may need to jackhammer the concrete to access and upsize the drain line — adding $800–2,000 to the plumber's scope

Some installers try to cheat this by keeping the 1.5" drain. Don't. If anything goes wrong with the shower later and an inspector or claim adjuster gets involved, the illegal drain becomes a liability issue. The homeowner's insurance may deny a claim. Your work gets tagged as the problem.

Plumber does this work. Not you.

The valve replacement requirement

When you demo the tub, you're disturbing the existing valve. Tub valves and shower valves have different spout configurations — a tub valve typically has a diverter and tub spout port that a shower valve doesn't need. Even if the shower valve body is similar, the trim kit is different.

Beyond that, modern code often requires pressure-balanced or thermostatic mixing valves in showers (anti-scald protection). Old tubs frequently have basic three-handle or simple single-handle valves that don't meet current shower code.

The realistic scope: when you demo the tub area, the plumber replaces the valve with a new shower-rated pressure-balanced valve. Not optional. Plumber's scope, not yours.

Supply line considerations

Depending on how old the house is and what's behind the existing tub, the plumber may need to:

• Replace galvanized steel or old copper supply lines
• Relocate the shower head rough-in to standard shower height (78–80" from floor) vs tub height
• Add a second shower head or rain head (common homeowner upgrade request)
• Move the valve location if the new shower layout differs from tub layout

All of this is plumber's scope. You coordinate schedule with the plumber, but the bill goes directly to the homeowner.

The homeowner conversation

"To convert a tub to a shower, we need a licensed plumber for several things that aren't in my scope as the tile contractor. The tub drain is 1.5 inches and code requires 2 inches for showers — that's not optional. The existing tub valve needs to be replaced with a shower valve. And depending on what we find when we open up the walls, the plumber may need to update supply lines. The plumber will bill you directly. Their work typically runs $1,500–3,000 for a standard tub-to-shower conversion. My estimate covers the tile work, demo, waterproofing, and substrate prep. Want me to recommend plumbers I work with regularly?"

Set this expectation BEFORE you quote. Homeowners need to understand they're hiring two trades (or a GC who coordinates both).

The Three System Choices (and Why They Change Your Pricing)

Before you quote, the homeowner needs to decide which system they're going with. Each has completely different scope, complexity, and pricing.

Option 1: Acrylic shower pan + custom tile walls

How it works:

• Existing tub area is demolished
• Licensed plumber installs a pre-formed acrylic or composite shower pan (Swanstone, Kohler, Sterling, Delta — various brands)
• Pan comes from factory pre-sloped with drain position specified
• You tile the walls over cement board or foam panel system
• Glass door installed at the end

Who does what:

• Plumber: demo assistance (tub removal), new drain, new valve, acrylic pan installation
• You: wall substrate prep, wall waterproofing, wall tile, grout, sealants
• Glass fabricator: frameless glass door or sliding door

Pricing: $7,500–10,500 for your tile scope

This is often the fastest and most affordable conversion path. The plumber handles the pan entirely — it's part of their plumbing scope to install the acrylic pan because it integrates with the drain and waterproofing. You stay out of the pan work and focus on walls.

Pros: - Fastest installation (pan drops in quickly) - Lower cost for homeowner - Fewer waterproofing failure points - Glass door options are more standard

Cons: - Limited design options (standard sizes, standard finishes) - Not as high-end a look as full custom tile - Some homeowners don't love the acrylic aesthetic next to tile walls

Option 2: Custom tile shower with curb

How it works:

• Existing tub is demolished
• New shower pan built from scratch with a raised curb (similar to a traditional custom shower)
• Either Kerdi/Wedi/Hydroblok foam panel system OR traditional drypack mortar bed
• You handle all pan and wall work
• Glass door installed at the end (requires templating after tile is done)

Who does what:

• Plumber: demo assistance, new drain, new valve, rough-in coordination
• You: substrate prep, pan system installation, waterproofing, all tile work (pan and walls), curb construction, niche, bench if applicable
• Glass fabricator: frameless glass or sliding door

Pricing: $10,000–14,000 for your tile scope

This is the "standard custom" option. More design flexibility than acrylic pan, easier construction than curbless, good mid-tier pricing.

Pros: - Full design flexibility - Custom sizing - Premium appearance - Proven reliability (curb contains water)

Cons: - Longer construction timeline (4–7 days of tile work) - Glass door more complex than over an acrylic pan - Curb is a tripping hazard (not ideal for aging-in-place clients)

Option 3: Custom curbless tile shower

How it works:

• Everything in Option 2, plus subfloor recession work to eliminate the curb
• Flush floor between bathroom and shower
• Linear drain or specialty drain placement
• Extended waterproofing (water can migrate onto bathroom floor without curb to contain it)

Who does what:

• Plumber: demo assistance, new drain, new valve, subfloor coordination
• Carpenter/framer (GC, homeowner, or specialty sub): subfloor recession (whose scope?)
• You: substrate prep, pan system installation (with sloped pre-sloped pan), waterproofing of larger area, all tile work, transition detailing, linear drain installation coordination
• Glass fabricator: frameless glass (often more complex due to fit requirements)

Pricing: $13,000–18,000+ for your tile scope

This is the premium option. The pricing multiplier reflects the subfloor recession work, extended waterproofing, linear drain complexity, and longer install timeline. See the full breakdown on curbless system choice — it applies here exactly.

Pros: - Highest-end aesthetic - Accessibility (no curb to step over) - Modern design preferred by many homeowners - Adds meaningful home value

Cons: - Highest price - Longest timeline - Requires subfloor work (scope question) - Requires precision execution (unforgiving of mistakes)

For high-end stone variants of any of these three options, see natural stone shower pricing for the additional handling, sealing, and substrate considerations.

The Demolition Hazards You Need to Price For

Tub demo is one of the most physically dangerous parts of any tile contractor's work. Pricing has to reflect the real cost of doing it safely.

Tub weight

Most homeowners — and many installers — dramatically underestimate how heavy a tub is.

• Standard acrylic tub: 50–80 pounds (easy to handle)
• Standard fiberglass tub: 60–100 pounds
• Standard steel tub: 100–150 pounds (two people)
• Cast iron alcove tub: 300–500 pounds (two people minimum, often more)
• Claw-foot cast iron tub: 400–600 pounds

A cast iron tub is the weight of a small refrigerator. You cannot safely remove it alone. Attempting to do so is how installers:

• Drop tubs through subfloors on second-floor bathrooms
• Crack tile or damage adjacent surfaces
• Injure themselves permanently (back, shoulders, knees)
• Damage doorframes and hallway walls during removal

Before you quote, know what tub you're dealing with

During the walkthrough:

• What's the tub made of? Cast iron, steel, fiberglass, or acrylic?
• What year was the home built? (Pre-1970 = likely cast iron)
• Is the tub on the main floor or upstairs?
• Is there clear access to haul it out, or does it need to be cut up in place?

Cast iron tub removal

For cast iron tubs, you have two options:

Option A: Remove intact — requires 2-3 people and specialized dollies or straps. Time: 1–2 hours. Risk: high (back injuries, damage to home).

Option B: Cut in place with a reciprocating saw or grinder — requires safety glasses, respirator, drop cloths for cast iron dust. Time: 2–4 hours. Risk: moderate (dust, noise, small fragments).

Either way, this is not "drop the tub off in the driveway" work. Price it accordingly.

The dump fee reality

The tub removal isn't done when it's out of the bathroom. You still have to dispose of it.

Standard disposal fees:

• Regular trash / construction dumpster: $30–80 (for lightweight fiberglass/acrylic)
• Cast iron or steel: $100–300 at the dump (weight-based pricing)
• Scrap metal recycling: sometimes you get PAID for cast iron ($20–50), but requires a trip to scrap yard
• Claw-foot or vintage cast iron tub: may have resale value, consider Craigslist or Facebook Marketplace before dumping

Always include dump fees as a line item in your estimate. A $250 cast iron dump fee eats your margin if you forgot to price it.

Substrate damage during demo

Cast iron tubs often sit on wood blocking that's rotted over decades of minor leaks. During removal, you may find:

• Rotted subfloor (visible once tub is out)
• Joists with water damage
• Mold behind the tub walls
• Plumbing issues invisible until demo

None of this is your fault — it's pre-existing damage — but the homeowner will need to address it before you can proceed with the new shower. The same liability on pre-existing conditions framework that applies to repair work applies here: document what you found, write the change order, get sign-off before you proceed.

Write this into your estimate:

"Demo may reveal pre-existing damage to subfloor, framing, or plumbing that isn't visible during the initial walkthrough. Any such damage discovered during demolition is not included in this estimate. If discovered, work will stop and a change order will be issued for the additional scope. Homeowner acknowledges that hidden damage is possible and accepts this as a normal part of bathroom renovation."

The Line-Item Breakdown

Here's what a proper tub-to-shower conversion estimate looks like:

Demolition

• Tub removal (pricing by tub type):
• Acrylic/fiberglass tub: $200–400
• Steel tub: $400–600
• Cast iron tub: $700–1,200 (requires 2 people, potentially cut in place)
• Wall tile demo (if existing tile on tub walls): $4–8/sq ft
• Surround material demo (fiberglass or acrylic surround): $200–400
• Dump fees: $150–400 depending on tub material and total volume
• Disposal trip: $100–200

Substrate repair (contingency)

• Subfloor repair if rot found: $300–1,200 (priced per situation)
• Minor framing repair: $200–600
• Plumbing modifications for non-plumber scope: coordinate with plumber

Waterproofing system

• Foam panel system (Wedi/Kerdi/Hydroblok pan + walls): $2,500–4,000 depending on size
• OR traditional drypack + sheet waterproofing: $1,800–3,200

Tile installation

• Wall tile (shower walls, 60–80 sq ft typical): $1,500–2,500 depending on tile and pattern
• Pan tile (if custom tile pan): $500–900
• Niche installation: $300–500
• Bench installation (if included): $700–1,200
• Grout and sealant: $300–500

Specialty items

• Linear drain (curbless option): $400–800
• Curb construction (curbed option): included in pan system
• Custom mitered corners: $75–150 per corner
• Natural stone upcharge if applicable: 50–80% premium over porcelain

Coordination

• Plumber coordination premium: $200–400
• Glass fabricator templating coordination: $200–300

Glass door (homeowner's separate cost, but often listed for reference)

• Frameless glass enclosure (separate trade): $1,500–3,500
• Sliding glass door: $800–1,500

When you tally these up, divide by your projected hours and verify the result against your real hourly rate on conversion work. If the number comes in under your floor, the estimate is wrong, not the work.

Real-World Pricing Example: Standard Tub-to-Shower Conversion

Let me walk through an actual conversion I priced recently.

The job:

• Existing alcove with 60" cast iron tub and tile surround (original 1985 construction)
• Client wants custom tile shower with curb (Option 2)
• Same 60" × 32" footprint as the tub
• 12x24 porcelain walls, 2x2 mosaic pan
• Kerdi waterproofing system
• Standard niche, no bench
• Frameless glass door (separate trade)
• Licensed plumber doing all plumbing work (separate)
• Homeowner providing tile

The estimate (tile contractor scope only):

Demolition - Cast iron tub removal (2 people, cut in place): $900 - Existing tile wall demo (120 sq ft wall surround): $600 - Dump fees (cast iron + tile debris): $350 - Disposal trip: $150

Substrate prep - Cement board removal and disposal: included in demo - Wall framing inspection and prep: $200 - Subfloor inspection and prep: $150

Waterproofing system - Kerdi shower system (curb pan + wall membrane): $800 materials - Kerdi-Board backer panels: $600 materials - System installation labor: $1,400

Tile installation - Wall tile (120 sq ft × $15/sq ft): $1,800 - Pan mosaic (18 sq ft × $25/sq ft for slope): $450 - Niche with mitered corners: $450 - Grout (walls cement, pan epoxy): $400

Coordination - Plumber coordination: $250 - Glass templating coordination: $200

Project total: $8,700

Plus homeowner's separate costs:

• Plumber (drain replacement, new valve, rough-in): $2,000–2,800
• Frameless glass door (separate fabricator): $2,200–2,800
• Tile materials (homeowner provides): varies by selection

All-in cost to homeowner: $13,000–14,500 for a quality tub-to-shower conversion with custom tile and curb. Matches the market rate in most US metro areas.

If the homeowner had wanted acrylic pan instead

Same bathroom, but Option 1 (acrylic shower pan):

• Demo stays the same: $2,000
• No custom pan work (plumber installs acrylic pan): -$1,400 from system cost
• Acrylic pan cost (plumber's scope, homeowner pays plumber): transferred from my estimate
• Wall waterproofing still required: $800 materials + $800 labor
• Wall tile stays the same: $1,800
• No pan mosaic work: -$450
• Niche stays the same: $450
• Grout (walls only): $250

Acrylic option total: $6,150 (vs $8,700 for custom tile option)

Homeowner saves $2,500 on my scope but may pay the plumber more for the acrylic pan installation. Net savings: $1,500–2,000 typically. Worth offering both options during the quote.

If the homeowner wanted curbless instead

Same bathroom, Option 3 (curbless):

• Demo stays similar: $2,000
• Subfloor recession required (whose scope? Varies): $1,200–2,000
• Linear drain unit + installation: $900
• Extended waterproofing (larger waterproofed area): +$500
• Pre-sloped foam pan system for curbless: $1,600 materials + $1,400 labor
• Wall tile stays similar: $1,800
• Pan tile with transition detailing: $600
• Niche with mitered corners: $450
• Grout: $400
• Glass door coordination (more complex for curbless): $300
• Plumber coordination: $300

Curbless option total: $11,050–12,250 (vs $8,700 for curbed tile)

Plus the homeowner's scope: plumber $2,000–2,800, subfloor recession possibly $1,500–2,500, glass $2,500–3,500. All-in for the homeowner: $17,000–21,000.

These tiers are also a useful sanity check against the percentage-based pricing system — conversions should land in your premium-job tier, not your standard-install tier.

The Walkthrough Questions Specific to Tub-to-Shower

Use the bathroom walkthrough process as your baseline, then add these tub-to-shower-specific questions on top:

About the existing tub

• What material is the tub? (Critical for demo pricing)
• How old is the home? (Pre-1970 typically means cast iron)
• Any known issues — leaks, grout failures, mildew problems?
• Is this the only bathtub in the home? (Accessibility/resale implication)

About the motivation for conversion

• Why convert from tub to shower? (Aging in place, design preference, accessibility need)
• Is the tub used at all currently, or is it a bath-shower that never gets a bath?
• Are there young children in the home? (May need at least one bathtub in the house)

Shower system preference

• Have you researched system options (acrylic pan, custom tile curbed, custom curbless)?
• Accessibility requirements? (Curbless strongly preferred for aging in place)
• Budget target?

Plumbing coordination

• Have you engaged a plumber yet?
• If not, do you want a recommendation?
• Is the plumbing accessible (basement, crawl space), or is this a slab home?

Design decisions

• What's going on the walls? Tile selected?
• Niche locations and quantities?
• Bench or no bench?
• Shower head configuration (single, dual, rain head)?

Glass enclosure

• Frameless or framed?
• Sliding or swinging door?
• Who's the glass fabricator (you coordinate, they bill homeowner directly)?

Scope coordination

• Is this part of a larger bathroom remodel, or just the shower conversion?
• Who's managing the project — GC, homeowner, or you as lead contractor?
• Timeline expectations?

Red Flags That Should Make You Decline

Sometimes the right call is walking away. Red flags for tub-to-shower conversions:

Homeowner refuses to hire a plumber. "My nephew can do the plumbing." No. Licensed plumber or walk. The drain code requirement and valve work are plumber scope, and liability sticks to you if the plumbing fails later and you didn't require a licensed pro.

Cast iron tub on second floor with no clear exit path. Can't remove intact through the hallway, can't cut in place because of asbestos concerns in older homes. Decline unless the scope is fully understood.

Pre-1978 home with possible asbestos. Cast iron tubs and tile surrounds from pre-1978 construction may contain asbestos in adhesives, backing boards, or old waterproofing. Requires asbestos testing before demo. Not your scope, but you need to confirm it's been handled.

Homeowner expects acrylic pan pricing for custom tile work. "I saw one-day shower conversions on TV for $4,000, that should be my price." Educate and walk away if they won't accept realistic custom tile pricing.

Slab home where drain relocation requires major jackhammering. If the scope explodes because of drain requirements, get the full picture before quoting. Sometimes it's cheaper for the homeowner to do a different layout than to move the drain.

Homeowner insists on keeping the old 1.5" drain. "We don't need to upgrade to 2 inches, it'll be fine." No. Walk. Non-compliant installations come back to you.

Scope confusion about plumber vs tile contractor responsibilities. If the homeowner or GC can't clearly define whose scope is what, your estimate will explode. Clarify before quoting.

Warranty Considerations

Tub-to-shower conversion warranties have multiple moving parts because of the multi-trade nature of the work.

Your workmanship warranty (1 year standard)

Covers: - Tile installation and grout - Waterproofing membrane or foam panel system (if you installed it) - Pan tile and slope (if custom pan) - Wall substrate work

Does NOT cover: - Plumber's work (drain, valve, supply lines) - Acrylic pan (plumber's warranty or manufacturer warranty) - Glass door (glass fabricator's warranty) - Existing conditions revealed during demo - Settling cracks from structural movement

Set expectations in writing

"The tile scope of this project is warranted for 12 months against workmanship defects. Plumbing work is warranted by the licensed plumber directly. Glass enclosure is warranted by the glass fabricator. Homeowner understands that the conversion involves multiple trades, each with their own warranty responsibilities."

Automating Tub-to-Shower Estimating

Tub-to-shower conversion pricing has unique variables — tub material (cast iron vs acrylic), system choice (acrylic pan vs custom curbed vs curbless), plumber scope boundaries, glass coordination, and dump fee calculations. Tracking these consistently across estimates is where margin gets lost.

TileForeman includes tub-to-shower conversion as a specific project type with built-in prompts for tub material selection (auto-adjusting demo pricing), system choice with pre-configured scope, and plumber coordination line items with clear exclusion language. Free during beta.

Wrapping Up

Tub-to-shower conversions are one of the most commonly mispriced residential tile jobs because installers either underprice the demo hazards or don't clearly separate their scope from the plumber's.

Price by system type: acrylic pan at $7,500–10,500, custom tile with curb at $10,000–14,000, custom curbless at $13,000–18,000+. Always separate your scope from the plumber's scope in writing. Never include plumber's work in your bundle. Know what you're dealing with during demo — cast iron tubs are dangerous and expensive to remove. Include dump fees as a line item. Coordinate timing with glass fabricator and plumber upfront.

Do this and tub-to-shower conversions become one of the highest-demand, highest-margin jobs in your schedule. Do it wrong and they eat your margin on every single one.

Next week I'll be covering how to price bathroom floor tile as a standalone job — the opposite of the tub-to-shower complexity, but a category where installers frequently underprice because "it's just floor tile."

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Cesare L. is a residential tile installer with 13 years of experience.