How Much to Redo a 100 Sq Ft Bathroom? Cost & Hiring Guide
Most Waukesha County homeowners redoing a 100 sq ft bathroom land at $15,000-$30,000 for a mid-range full remodel in 2026, depending on whether plumbing stays in place or gets moved. At the per-square-foot level, that works out to roughly $120-$275/sqft. Budget cosmetic refreshes can come in closer to $7,000-$10,000; high-end gut-and-redo projects with custom tile, a frameless glass enclosure, and a soaking tub push well past $30,000. Or call John at (262) 352-9525.
If you’re comparing contractors right now, this guide covers what your project should cost, which permits you’ll need, and how to vet a contractor before you sign anything.
A 100 sq ft space is the benchmark for a reason: it’s a full master bath or a generous guest bath, not a powder room, not a spa suite. It’s large enough that every trade shows up on the invoice, which makes it the clearest lens for understanding where remodeling money actually goes. Run your own numbers with our bathroom cost calculator before your first contractor meeting.
Cost Breakdown: Where the Money Actually Goes
Every line item below represents a real trade with real labor and material costs. When you’re comparing bids, check each category, a quote that skips a line isn’t cheaper, it’s incomplete.
| Line Item | Typical Range | Notes |
|---|---|---|
| Demo & haul-away | $1,000-$2,500 | Often omitted from low-ball quotes |
| Tile labor + waterproofing | $3,000-$7,000 | Ceramic baseline; stone adds labor |
| Plumbing, fixture swap | $2,000-$5,000 | Same-location swap only |
| Plumbing, moving rough-in | Add $2,000-$5,000 | Cutting floor system or concrete |
| Electrical (GFCI, fan, lighting) | $1,200-$2,500 | Per Wisconsin SPS 316 requirements |
| Permits & inspections | $100-$1,000 | Municipality-dependent |
| Vanity, mirror, storage | Varies by tier | Stock vs. semi-custom vs. custom |
| Shower/tub (tile-in custom) | Varies by spec | Frameless glass enclosure adds cost |
| Drywall, paint, trim | Varies by scope | Moisture-resistant board in wet areas |
Demo and Haul-Away
Stripping a 100 sq ft bathroom to the studs, tile, drywall, fixtures, subfloor if needed, runs $1,000-$2,500 in labor . Dumpster or haul-away fees are separate and frequently omitted from low-ball quotes. Ask every contractor: is debris removal a line item in your bid?
Tile, Floor and Shower/Tub Surround
Ceramic tile (the budget workhorse) costs significantly less per square foot than porcelain or natural stone. Professional tiling and waterproofing labor runs $3,000-$7,000 for a bathroom this size . A straight-lay ceramic floor is at the low end; large-format porcelain with a herringbone shower surround requires more cuts, more waste, and more labor hours.
Pro Tip: Ask your contractor what tile allowance is baked into the quote, typically expressed as a dollar-per-square-foot material budget. If you pick tile above that allowance, the difference comes back as a change order. Know the number before you fall in love with a slab at the tile showroom.
Plumbing, Fixture Swap vs. Moving Rough-In
Swapping a toilet, vanity faucet, and shower valve in their existing locations is a half-day job. Moving a drain line, relocating a toilet, shifting a shower pan, or adding a second sink, can add $2,000-$5,000 in rough-in labor alone . That single decision is the biggest cost lever in any bathroom remodel.
Electrical, GFCI, Exhaust Fan, Lighting
Wisconsin’s electrical code (SPS 316, which adopts the National Electrical Code) requires GFCI protection, ground-fault circuit interrupter outlets that cut power instantly if they detect a ground fault, within 6 feet of any water source. An exhaust fan upgrade and new vanity or recessed lighting typically run $1,200-$2,500 in labor .
Watch Out: Some low-ball quotes list "electrical" without specifying whether the exhaust fan is replaced or just reconnected. An undersized exhaust fan in a 100 sq ft bathroom causes moisture buildup, mold, and paint failure within two years. Specify CFM rating in the scope.
Permits and Inspections
Wisconsin permit fees for plumbing, electrical, and construction work run $100-$1,000 depending on municipality and scope . They’re not optional if you’re moving plumbing or changing electrical circuits, and they protect you at resale.
What Pushes the Price Up, and What Keeps It Down
Four decisions drive most of the cost variance in a 100 sq ft bathroom remodel. Three are yours to control; one isn’t.
1. Moving vs. keeping plumbing in place. This is the single biggest variable. Keeping the toilet, shower, and vanity in their existing drain locations saves thousands. The moment you move a drain line, even a few inches, you’re cutting into a floor system or concrete slab, and the cost jumps accordingly .
2. Tile selection and pattern complexity. Ceramic tile in a standard straight lay is the budget baseline. Porcelain adds cost. Natural stone adds more, plus requires sealing and more careful installation. Pattern complexity, herringbone, basketweave, large-format with tight grout joints, increases labor hours and tile waste across 100 sq ft of floor and a full shower surround.
3. Fixture grade. Builder-grade fixtures are functional and affordable. Mid-grade fixtures from brands like Kohler or Moen hit a quality-to-cost sweet spot. Luxury fixtures, Brizo, Waterworks, are a different price tier entirely. The fixture spec in your quote should match what you actually want in the finished bathroom.
4. Structural surprises after demo. This one isn’t in your control. In a 1970s Menomonee Falls colonial or a 1980s Brookfield ranch with a bathroom that’s never been fully gutted, there’s a real chance of finding subfloor rot, mold behind the shower wall, or deteriorated backer board once tile comes off.
In 2024, we quoted a Pewaukee bathroom at $19,000. The homeowner’s initial budget was $18,500. After demo, we found the subfloor under the toilet had been slowly rotting from an undetected wax ring leak, sistering new joists and replacing the subfloor section added $2,800 to the final bill, bringing the total to $21,800. The learning point: always budget a 10-20% contingency for homes built before 1990. Water damage behind tile is invisible until the wall comes down.
Labor accounts for roughly 50% of a typical bathroom renovation budget, which means the cheapest labor quote often carries the most schedule and quality risk.
We'd rather lose a job by being honest about the real number than win it on a lowball and bleed change orders later.
John, T&J co-founder · 14 yrs PM in Waukesha County
What a Complete Scope of Work Looks Like (vs. a Low-Ball Quote)
The construction industry has no standardized quote format. That’s why two bids at the same price can represent completely different projects, and why the homeowner who goes with the lowest number sometimes ends up paying more than the highest bid by the time the job is done.
A complete bid for a 100 sq ft bathroom remodel should include, in writing:
- Every trade listed explicitly, demo, plumbing, electrical, tile, carpentry, painting.
- Material allowances called out, tile at $X/sqft, vanity at $X budget. Not buried in a lump sum.
- Permit pulling, included or explicitly excluded with a stated reason.
- Debris removal, demo generates a full dumpster of material. Who hauls it?
- Subcontractor names or "owner-performs", who is actually doing the plumbing, and are they licensed?
- Waterproofing membrane, a product like Schluter Kerdi or RedGard behind shower tile is non-negotiable. It’s also one of the first things cut from a low-ball quote.
- Backer board specification, cement board in wet areas, not standard drywall.
- Warranty terms, what’s covered, for how long, and who you call.
- Payment schedule, milestone-based, not front-loaded.
Watch Out: The most commonly omitted line items are permit fees, haul-away, waterproofing membrane, backer board, exhaust fan upgrade, finish carpentry, and touch-up paint. None are optional, they get added back as change orders after you've signed.
The cheapest quote often has the shortest scope, not the best price. A $14,000 bid that excludes permits, waterproofing, and haul-away will cost more than a $17,000 bid that includes all three, you just won’t know it until you’re mid-project. Understanding the most common bathroom remodel mistakes that blow budgets starts with recognizing an incomplete scope before you sign.
John walks through scope line-by-line with every homeowner before a contract is signed, not to upsell, but because mid-project surprises are worse for everyone.
How Long Does a 100 Sq Ft Bathroom Remodel Take?
A full gut-and-redo at 100 sq ft typically runs 2-4 weeks from demo to final walk-through, assuming no hidden structural damage.
| Phase | Typical Duration |
|---|---|
| Demo & haul-away | 1-2 days |
| Rough-in plumbing & electrical | 2-3 days |
| Rough-in inspections | Variable, build in buffer |
| Tile (floor + shower surround) | 3-5 days |
| Tile mortar + grout cure time | 24-72 hours minimum |
| Fixtures, vanity, finish work | 2-3 days |
| Final inspection | Variable |
Wisconsin permit inspections add calendar time, rough-in plumbing and electrical must pass inspection before walls close. That’s not a delay; it’s the protection you’re paying for. A contractor who promises a 5-day full bathroom remodel is either skipping inspections, skipping cure time, or both.
Our typical booking lead time is 4-8 weeks depending on season, spring and fall book fastest in Waukesha County. For a deeper look at what affects the schedule, see how long a full bathroom remodel typically takes.
Permits for a Bathroom Remodel in Wisconsin: What You Need to Know
Code Note: Wisconsin's Uniform Dwelling Code (UDC), administered by the Wisconsin DSPS, requires permits when you move or add plumbing, change electrical circuits, or make structural changes. Wisconsin Plumbing Code SPS 382 governs drain, waste, and vent work, any relocation of a drain line requires an inspection before the floor closes. A cosmetic swap, new vanity in the same location, new tile over existing substrate, typically doesn't require a permit.
Three reasons you don’t skip a required permit:
- Insurance. If unpermitted plumbing or electrical work causes a water leak or fire, your homeowner’s insurance carrier can deny the claim on the grounds that the work wasn’t inspected and approved.
- Resale. Wisconsin requires disclosure of known unpermitted work at sale. Buyers’ inspectors find it. It becomes a negotiating chip against you at closing.
- Retroactive inspection. A municipality can require you to open finished walls to inspect unpermitted work. The cost of reopening tile and drywall is entirely yours.
In Wauwatosa and New Berlin, plumbing permit fees for a standard bathroom rough-in typically run $200-$350; in Brookfield and Elm Grove, expect a similar range. Permit fees vary by municipality, your contractor should know the local schedule before quoting. Read more about whether your bathroom remodel needs a permit in Wisconsin before you decide.
Getting an Accurate Quote for Your Bathroom Remodel
A 100 sq ft bathroom remodel is a real investment, the range is wide because scope varies, not because contractors are arbitrary. The homeowner who understands what a complete scope looks like, knows the right questions to ask, and compares bids line-by-line will always get a better outcome than the one who goes with the lowest number.
Telli and John bring 35+ years of combined remodeling experience to every project across Waukesha County. We’re a father-son operation, the owners are on every job, not delegating to a crew you’ve never met. John handles every project communication personally; Telli is on-site running the work. Free in-home consultation, no obligation. We walk through your scope before anything is signed so you know exactly what your remodel costs, and why, before you commit.
See the full range of what we do on our bathroom remodeling services page. Or call (262) 352-9525 to schedule your free in-home consultation.
Frequently asked questions
Is $10,000 enough to redo a 100 sq ft bathroom?
$10,000 is tight for a full 100 sq ft remodel in 2026, but it's workable for a budget cosmetic refresh, new fixtures, a stock vanity, basic ceramic tile, and paint, with plumbing staying exactly in place. Here's why it's tight: labor alone accounts for roughly 50% of a bathroom renovation budget, which means $5,000 of that $10,000 goes to labor before a single tile is purchased. Tile and fixtures consume most of what's left. The deeper constraint is that Wisconsin labor rates and material costs have risen since 2026, a quote that sounds like a full remodel at $10,000 almost certainly has a short scope. If you want a gut-and-redo with moved plumbing or upgraded tile, the number needs to be in the $15,000-$30,000 range. Ask any contractor quoting under $12,000 for a full remodel to walk you through every line item, the exclusions will tell you what you're actually buying.
What's included in a full bathroom remodel vs. a partial remodel?
A full remodel (gut-to-studs) includes demo, waterproofing membrane, cement backer board, tile, plumbing rough-in, all fixtures, vanity, electrical, drywall, paint, and trim. A partial remodel swaps out surfaces or fixtures without touching the structure or plumbing rough-in. The distinction matters when comparing quotes: two bids at the same price may have completely different scopes. Contractors who quote "full remodel" without specifying what's included are leaving themselves room to exclude expensive line items, waterproofing membrane and subfloor repair are the most commonly omitted. Ask specifically: "Does your quote include waterproofing membrane behind the shower tile and cement backer board in all wet areas?" A vague answer means the scope is incomplete.
Why are bathroom remodel quotes so different from contractor to contractor?
Scope is the main reason, not skill level or profit margin. One contractor includes permit fees, haul-away, and a waterproofing membrane; another doesn't. One uses a licensed plumber registered under Wisconsin's SPS 305 plumbing contractor requirements; another uses a handyman. One has a project manager on-site daily; another drops off a sub-crew and checks in weekly. The price difference reflects what's in the quote, not what the finished bathroom will cost you. The underlying reason this is so common: the construction industry has no standardized quote format, so homeowners are comparing apples to oranges unless they ask for a line-item scope from every contractor. A $3,000 price gap between two bids often disappears entirely once you add the permit fees, haul-away, and waterproofing that the lower bid excluded.
Do I need a permit to remodel a bathroom in Wisconsin?
In Wisconsin, permits are required when you move or add plumbing, change electrical circuits, or make structural changes, governed by the Uniform Dwelling Code (UDC) and Wisconsin Plumbing Code SPS 382. A cosmetic swap, new vanity in the same location, new tile over existing substrate, typically doesn't require a permit. The first reason to pull a required permit is insurance: if unpermitted plumbing causes a water leak, your homeowner's insurance carrier can deny the claim because the work wasn't inspected. The second reason is resale: Wisconsin requires disclosure of known unpermitted work, and buyers' inspectors find it, it becomes a negotiating chip against you at closing. The third reason is the most expensive: a municipality can require you to open finished walls for a retroactive inspection, and the cost of reopening tile and drywall is entirely yours. A reputable contractor pulls the permit for you, if a bid excludes this, ask why.
How long does it take to remodel a 100 sq ft bathroom?
A full gut-and-redo at 100 sq ft typically runs 2-4 weeks from demo to final walk-through, assuming no hidden structural damage. The phases that add time are permit inspections, Wisconsin requires rough-in plumbing and electrical to be inspected before walls close, and tile cure time. Tile mortar needs 24-48 hours to cure before grout is applied; grout needs another 24-72 hours before fixtures are set. The reason rushing cure time is a problem: mortar that hasn't fully cured flexes under foot traffic, which cracks grout joints within months and leads to water infiltration behind the tile, the exact failure mode you were trying to prevent with the remodel. A contractor who promises a 5-day full bathroom remodel is either skipping inspections, skipping cure time, or both.
What's the biggest hidden cost in a bathroom remodel?
Subfloor and wall rot discovered after demo is the most common budget surprise in bathrooms over 20 years old, especially where a slow wax ring leak or shower pan failure went undetected for years. A complete scope includes a contingency line of 10-20% of total budget for exactly this reason. Water damage behind tile is completely invisible until the wall comes down, once it's exposed, you can't close the wall back up. You're sistering joists, replacing subfloor sections, and treating for mold before any new tile goes up. A contractor who doesn't mention contingency in their quote either hasn't done enough bathrooms or is keeping the quote artificially low to win the bid. Ask every contractor: "What happens to the price if we find rot behind the shower wall after demo?", their answer tells you exactly how they handle the unexpected.
Get a real number for YOUR project
Cost ranges only get you so far. Tell us the room, scope, and zip — we’ll send back an honest estimate within one business day.
Estimates: open this week. New project starts are typically 4-6 weeks out, so the earlier we walk your space, the more flexibility you have on a start date.
