Bathroom Plumbing Remodeling in Chicago, IL

Most bathroom remodels in Chicago are led by a general contractor or a bath-system installer who focuses on visible finishes — tile, vanity, fixtures, lighting. That approach routinely skips or cuts corners on the plumbing behind the walls. The result: problems that surface six months to five years after the remodel is "done."

What We See on Rework Calls

• Undersized supply lines — homeowner added a rain head plus two body sprays, but the existing 1/2" line can't feed them. Pressure is weak, handheld starves the rain head.
• Improperly vented traps — new fixture was added without a proper vent, so water siphons from the trap and the room fills with sewer gas.
• Drain slope errors — shower drain was set flat (0% slope) or reverse-sloped, leading to slow drains and standing water.
• Hidden leaks in the wall — improperly soldered copper or compression fittings buried behind tile leak slowly for months. The wet drywall delamination shows up as bubbled paint near the baseboard.
• Code-violation toilet flange — old lead bend was cut to the wrong height or wasn't replaced. Wax ring fails in year 2.
• Anti-scald valve not installed — Chicago and IPC require anti-scald tub/shower valves since 1994. Many 1990s – 2000s remodels skipped this; every failure is a lawsuit waiting to happen.
• Cast iron stack tied into with no proper fitting — homeowner's contractor used a rubber coupling where a shielded transition was required.

What "Doing It Right" Costs

Nothing extra. Proper plumbing costs the same as improper plumbing — maybe 5 – 10% more for the right fittings and fixtures. The expense comes later, when the improper install fails and you open walls to fix it. We do it right the first time.

We scope every bathroom remodel with the GC or homeowner before any permit is pulled. Typical scope items:

Rough-In Plumbing

• Water supply lines — copper or PEX from the main trunk to every fixture, sized per fixture unit calculation
• Drain / waste / vent (DWV) piping — PVC or cast iron per Chicago code, with correct slope, cleanouts, and venting
• Tub or shower drain rough-in — set at exact elevation and slope
• Toilet flange — set to finished floor height with proper wax ring specification
• Vanity and sink supply and drain stub-outs
• Washing machine hookup (if laundry is in the bath area)
• Steam shower rough-in (if applicable)
• Radiant floor heat rough-in (coordinated with HVAC or hydronic installer)

Finish Plumbing

• Toilet installation — wax ring, supply line, mounting, sealing, test flush
• Vanity sink and faucet installation — supply valves, faucet mount, drain assembly, P-trap
• Bathtub installation — freestanding, alcove, or drop-in
• Shower valve trim installation and body spray hookups
• Shower drain and pan drain testing
• Towel warmer hookup (if hydronic or electric with plumbing integration)

Layout Changes

• Moving a toilet — extending the waste line with proper slope, adding venting if needed
• Relocating a shower or tub — running new drain and venting
• Converting tub to shower (or vice versa) — new drain, new valve, new supply
• Adding a second sink — extending hot/cold and drain
• Expanding into a closet or adjacent room — tie-ins to existing DWV and supply

Fixture Upgrades

• Anti-scald valves — retrofit to meet current code
• Low-flow toilets — 1.28 gpf or 0.8 gpf flush
• High-efficiency fixtures — faucet aerators, showerheads
• Thermostatic mixing valves — for scald protection on hot-water-only lines

Hidden System Issues

• Galvanized supply replacement — when walls are open, it's the right time
• Lead drum trap removal — common in pre-1940 Chicago bathrooms
• Cast iron drain stack evaluation and replacement — see our drain replacement page
• Venting corrections — bringing old non-vented or mis-vented systems to code
• Shut-off valve additions — modern remodels require individual shut-offs per fixture

If we rank Chicago bathroom remodel scopes by call volume, tub-to-shower conversion is #1. Here's what's involved and what it costs.

Why the Conversion Is Popular

• Aging-in-place — walk-in showers are safer and easier to access than tubs
• Second-bathroom utility — if another bathroom has a tub, this one doesn't need to
• Space feel — modern walk-in showers open up small bathrooms visually
• Resale value — in most Chicago markets, a modern walk-in shower adds value (but keep at least one tub in the home for buyers with young children)

Plumbing Scope for a Tub-to-Shower Conversion

1. Demo the tub — disconnect supply, remove the tub, haul away
2. Convert the drain — tub drains are at one end; shower drains are centered in the pan. This almost always requires relocating the drain, which means opening the floor or ceiling below.
3. Reconfigure the drain trap and vent — shower pan drains connect differently than tub drains
4. Replace the valve — old tub valves are not suitable for a walk-in shower; new pressure-balancing or thermostatic anti-scald valve required
5. Run new supply lines if needed — for body sprays, rain head, handheld
6. Install waterproof shower pan — in tile showers, the pan is a separate layer from the tile work; in prefab units the pan is integrated
7. Connect new shower drain to reconfigured trap
8. Pressure test and water test — mandatory before tile

Typical Cost

• Simple direct conversion (tub out, shower in, same footprint, same drain): plumbing portion $1,800 – $3,500
• Expanded walk-in shower (bigger than the tub footprint, drain relocated): $2,500 – $5,500
• Luxury conversion (curbless, linear drain, multiple heads, body sprays, steam unit): $4,500 – $12,000+

See our shower installation page for shower-specific scope and bathtub page for opposite direction remodels.

Many Chicago homeowners want to upgrade from a single small bathroom to a full master suite. Here's what that entails plumbing-wise.

Where the Bathroom Goes

Most master bath additions carve space from an existing bedroom, hall closet, or attic/dormer area. Plumbing must tie in to an existing DWV stack — ideally within 10 feet of the existing bath so drain slope math works.

Key Plumbing Considerations

• DWV tie-in — new vent stack or tie into existing (permit required in Chicago)
• Supply extension — run hot and cold from the nearest trunk; may require upsizing the trunk
• Water heater capacity — a master bath often adds 40 – 80 gallons of fixture demand; upgrading the water heater may be needed (see water heater installation)
• Sewer lateral capacity — a 4-fixture master suite increases lateral demand; for older Chicago homes with clay or Orangeburg laterals, a sewer camera inspection before scoping is smart
• Double vanity — two supply lines, two drain lines, shared trap or separate traps depending on design
• Freestanding tub — floor-mounted filler vs. deck-mounted; floor drain placement
• Walk-in shower — separate drain, separate valve, often larger supply for multiple heads
• Water closet — usually a separate room or at least a partial partition; relocating an existing toilet is simpler than adding from scratch

Typical Cost for Plumbing Portion

• Basic master bath rough-in (tie into existing stack, 4 fixtures, simple layout): $4,500 – $8,500
• Full master bath plumbing (expanded stack, new venting, 5 – 6 fixtures, upgraded supply): $7,500 – $15,000+

This is just the plumbing scope. Total master bath remodel (including GC, tile, cabinetry, electrical, HVAC) typically runs $35,000 – $80,000+ in Chicago.

Here's a breakdown of typical plumbing costs for Chicago bathroom remodels. Total remodel cost (including GC, tile, cabinetry, fixtures, electrical, HVAC, paint) is 3 – 5x the plumbing portion.

What the Plumbing Cost Includes

• All labor for rough-in and finish plumbing
• Code-compliant piping and fittings (copper or PEX supply; PVC or cast iron DWV)
• Standard shut-off valves and trim
• Pressure testing
• Chicago permits and inspection coordination
• 2-year labor warranty on workmanship

What's Not Included

• Finish fixtures — toilets, faucets, tubs, vanities (these are specified with you based on design and budget)
• Tile, drywall, paint, cabinetry, mirrors, lighting — coordinated with your GC
• Electrical work — handled by your electrician
• HVAC (including radiant floor heat) — coordinated with HVAC contractor

We can also supply fixtures through our vendor accounts, which often gives you 10 – 20% savings vs. retail.

Bathroom remodels trigger Chicago plumbing permits for almost every scope beyond a simple fixture swap. Here's what to expect.

When a Permit Is Required

• New fixture installation (adding a fixture that wasn't there before)
• Moving any fixture (toilet, sink, tub, shower to a new location)
• Adding or modifying supply or drain lines
• Adding or modifying venting
• Any layout change

When a Permit Is NOT Required

• Direct replacement of an existing fixture (toilet-for-toilet, faucet-for-faucet, etc.) in the same location with the same type
• Cosmetic work (paint, trim, mirror) with no plumbing change

Permit Process

1. Scope finalization with homeowner/GC
2. Permit application by our licensed plumber (Chicago requires a licensed plumber of record for all permits)
3. Plan review for larger remodels (full-bath additions, master suite work)
4. Rough inspection — after piping is in, before drywall and tile
5. Final inspection — after fixtures are set and system is operational

Chicago Code Highlights (2024 Amendments)

• Anti-scald pressure-balancing or thermostatic valves required on all tub/shower installations
• Individual shut-off valves required at every fixture
• Accessible valve access panels required for bathtub valves on hidden walls
• Minimum slope of 1/4" per foot for drain lines
• Proper venting (IPC chart) for every trap
• Water heaters serving bathrooms require appropriate capacity and code-compliant T&P relief and seismic strapping (not a Chicago requirement but good practice)
• Cast iron drain stacks in buildings over 4 units or 3 stories (Chicago code)

We handle all permits, scheduling, and inspector coordination. Your GC gets clear sign-off without chasing the city.

A smooth bathroom remodel is a choreographed dance between plumbing, drywall, tile, cabinetry, electrical, and HVAC. Here's how we fit in.

Phase 1: Pre-Demo Planning (Day -14 to Day 0)

• Walk the site with the GC and homeowner
• Mark proposed fixture locations
• Identify existing supply, drain, and vent locations
• Review permit scope with the GC
• Coordinate schedule for rough-in

Phase 2: Demo (Day 1 – 3)

• GC demos to the studs
• We cap existing supply and drain stubs so other trades can work safely
• Identify hidden issues (galvanized supply, lead drum traps, cast iron deterioration, prior code violations)

Phase 3: Rough-In (Day 3 – 8)

• Supply lines installed (copper or PEX) with shut-off valves
• DWV piping installed with correct slope and venting
• Toilet flange set to correct height
• Tub/shower valve installed with access panel planned
• Pressure test of all supply piping (50 PSI for 15+ minutes)
• Rough inspection called

Phase 4: Drywall, Tile, Cabinetry (Day 8 – 20)

• Other trades work while plumbing is dormant
• We stay on call for coordination questions (fixture spacing, etc.)

Phase 5: Finish Plumbing (Day 20 – 22)

• Install toilet, sink, faucet, tub, shower valve trim, showerhead, handheld, body sprays
• Connect all supplies and drains
• Test every fixture under full operation
• Verify no leaks, proper pressure, correct temperature

Phase 6: Final Inspection (Day 22 – 25)

• Call Chicago inspector
• Pass inspection on first visit (our standard)
• Deliver final documentation to homeowner

Phase 7: Warranty

• 2-year labor warranty on workmanship
• Manufacturer warranties on all fixtures
• Call-back priority for 90 days post-completion

We don't disappear after the final invoice. If something needs tweaking, we come back.