Renovation decision guide / 9 min read
What actually happens in a bathroom remodel?
Most of the nerves about signing a remodel contract come from not knowing what the weeks actually look like, or which decisions are about to land on you and when. The order of the work is fixed, and so is the moment each choice comes due. Two of those moments decide whether the room holds up.
Short answer
A bathroom remodel runs in a fixed order: protection and demolition, then plumbing and electrical rough-in, then an inspection, then waterproofing, then tile, then finishes. Two of those stages carry the weight. Nothing may be covered until the rough-in inspection passes, so that approval sets the schedule for everything after it. Waterproofing is the layer nobody ever sees again, and the only one whose failure shows up years later as damage to the framing. The decisions that trip homeowners up are the ones due before the walls close, not the ones about finishes.
Demolition first, finishes last, and one gate in the middle
A bathroom remodel runs in a fixed order. Protection and demolition, then rough-in for plumbing and electrical, then an inspection, then waterproofing, then tile, then finishes. Each stage buries the one before it, so the work only runs in one direction and cannot jump ahead.
Two of those stages decide whether the room holds up. The rough-in inspection is one, because nothing may be covered until it passes. Waterproofing is the other, because it is the layer that gets covered over and never looked at again, and the only one whose failure shows up years later as damage to the framing below.
The order, and what each stage decides for you
The column most homeowners have never seen is the third one. Selections do not land when an item gets installed. They land while the wall is still open, well before most people expect to be asked.
| Stage | What is happening | Settled before it starts |
|---|---|---|
| Protection and demolition | Path in gets covered, fixtures out, tile and drywall off to the studs | The written procedure for anything found behind the wall |
| Discovery | What the walls were hiding comes into view and gets a number put on it | How a discovery gets billed |
| Plumbing and electrical rough-in | Lines set, fan duct run, circuits pulled, blocking added | Exact fixtures, valve, fan, and the position of each |
| Rough-in inspection | The city looks at all of it while it is still visible | Nothing. A scheduled wait, not lost time. |
| Waterproofing and backing | Backer board, pan or membrane, seams, corners, curb | Shower footprint, curb or curbless, drain type |
| Tile and stone | Set, then grout, then cure | Tile, layout, grout color, edge treatment |
| Finishes | Vanity, top, fittings, mirror, glass, paint, trim | All of it, chosen weeks earlier |
| Final inspection and punch list | The permit closes, then the short list gets cleaned up | Nothing |
A job sits still when nobody has picked the shower valve by the end of demolition. The valve body goes inside the wall, and the wall does not close without it.
Demolition is when the job finds out what it actually is
Nobody can quote what they cannot see, and a bathroom hides more in a small footprint than any other room. What routinely turns up in the first two days:
- A subfloor gone soft around the toilet flange, from a wax ring weeping quietly for years
- A shower pan that was never really a pan, just mortar and tile over plastic with a folded corner
- A cast iron or galvanized drain line, sound in places and scaling shut in others
- The vent stack sitting in the exact wall you wanted to open up
- Framing no longer square, because the house moved on clay soil and the room moved with it
None of that means you were quoted badly. It does mean that the paragraph in your contract about how a discovery gets billed deserves a careful read before demolition day.
What “move the shower” means depends on your foundation
This is the difference almost no quote explains, and it drives more of the schedule than any finish you pick.
On a slab-on-grade house, drain lines are cast into the concrete or run beneath it. Moving a toilet, shower drain, or tub waste more than a few inches means cutting the slab open, trenching, re-plumbing, having that work inspected while the trench is still open, then patching the concrete back. The work itself is straightforward, but it is a separate phase with its own inspection and its own drying time, and it sits in front of everything else.
On a pier-and-beam house, those same lines hang below the floor joists. Moving one is a day spent under the house instead of a concrete job. The trade-off is what else is down there: joists that earlier trades notched where they should not have, and a crawlspace that may need access and drying work first.
Two things hold either way. Drain lines need continuous fall toward the main, so a drain cannot go just anywhere at just any depth. And the vent has to go somewhere, which is why a wall you assumed was empty sometimes cannot come out.
Moving a vanity is a small change. Moving a drain is a different job with a different sequence.
Rough-in, and the inspection nothing gets covered without
Rough-in is everything that will be invisible once the walls close. Supply lines, drain and vent, the shower valve body, the exhaust duct, circuits, and the blocking inside the wall that a grab bar or heavy mirror will need later.
Then the work stops and waits for an inspector. The Town of Flower Mound states the rule plainly in its residential construction packet: “Construction or work for which a permit is required shall be subject to inspection, and such work shall remain accessible and exposed for such purposes until approved.” No drywall, no backer board, no tile until that approval exists. That packet also shows plumbing rough and top-out as separately scheduled inspections, each with its own prerequisites, though the list it lays out is written for new construction. Which inspections land on a remodel permit is a question for your own city. Ask before demolition starts.
That pause is not slack in the schedule. It is the schedule. A contractor who offers to close the walls over the weekend and sort the inspection out afterward is handing you a problem and calling it a favor.
Rough-in is also the last easy moment for the things people ask about too late:
- Blocking for a grab bar is two pieces of lumber and ten minutes now, or a wall opened back up later.
- A shower niche has to miss the studs, the vent, and the plumbing, so it gets located now or not at all.
- Flower Mound requires GFCI protection on every 120 volt, 15 and 20 amp outlet in a wet location. If the outlet in your bathroom has no test and reset buttons, and nothing upstream of it has them either, that gets corrected here.
Ventilation gets settled here too. The Department of Energy’s Building America Solution Center puts bathroom local exhaust at a minimum of 50 cfm for a fan running intermittently, or 20 cfm running continuously, and says to vent it outdoors, not into an attic, crawlspace, or space between floors. Flower Mound’s packet says it in one line: “All exhaust fan ducts must extend to the outside.” A fan discharging into your attic is moving your shower’s moisture into your insulation.
There may also be a second fan you have not planned for. If your layout puts the toilet behind its own door, Flower Mound requires that “Where a water closet is separated from the shower area by a door, an exhaust fan is required in both the water closet area and the main bath area.”
Fixture specs lock here as well, so look at flow rates before anything gets installed. The EPA’s WaterSense program certifies labeled bathroom sink faucets to a maximum of 1.5 gallons per minute, against a standard flow of 2.2 gallons per minute.
Code editions are adopted city by city, not statewide. Flower Mound lists the 2024 IRC and the 2023 NEC among its adopted residential codes, effective 10.1.2025. Your city may sit on a different edition and run a different inspection list.
Waterproofing, the layer nobody ever sees again
Tile and grout both let water through. Behind them sits the actual barrier, either a pan liner or a bonded membrane, along with the way the corners, the curb, and the drain connection are treated. That assembly is the room’s entire defense against water, and once tile covers it nobody looks at it again.
It also gets tested. Flower Mound requires that test at plumbing top-out wherever tubs and shower liners go in: “All tubs, shower liners, and receptors shall be tested at this inspection.” The drain gets plugged, the pan gets filled with water, and everybody waits to see whether the level drops. Whether that test lands on your remodel permit depends on your city and your scope, so ask. If it is on the list, be home for it. It is the one inspection a homeowner can stand in the doorway and fully understand.
A failure here does not announce itself. The EPA’s guidance on mold and moisture states that “It is important to dry water-damaged areas and items within 24-48 hours to prevent mold growth,” and that “If you clean up the mold, but don’t fix the water problem, then, most likely, the mold problem will come back.” Water moving slowly behind tile does not get dried inside that window, and nobody can see it to know it is there. That is how a shower turns into a framing repair.
Three things to require in writing before anyone covers it:
- Which waterproofing system is going in, named specifically, and whether it is a pan liner or a bonded surface membrane
- How the curb, the corners, and the drain connection are treated, since those are where these assemblies fail
- Photographs of the rough-in and of the finished waterproofing before anything goes over them
Almost nobody asks for the photographs, and they are the easiest thing on that list to get. They also become the only record of what is inside your wall when you sell or file a claim.
Finishes, and the stretch where it looks like nothing is happening
Tile gets set, then grouted, then left to cure. Vanity, top, fittings, mirror, paint, and trim follow. Then the room looks finished and there is still a wait. Shower glass is normally measured after the tile is set, so it gets ordered at the point the room already looks done. That is the most common reason a job feels stalled at the end. The lead time could only start once the tile stopped moving.
Why two scopes for the same bathroom are not the same job
A scope listing a vanity, a tile allowance, and a fixture package has described the visible half. A scope that also says what is being opened, whether the slab is being cut, which waterproofing system goes in, and which inspections close the permit has described the whole job. Those two will not match, and the lower bid is usually the one that decided less. More on how that gap opens in why renovation quotes balloon.
What to ask at each gate
- Before demolition, ask how anything found behind the wall gets billed, and whether the work stops for your signature first.
- Before rough-in, ask whether every fixture, valve, and fan is confirmed on paper, and have the niche, blocking, and outlet locations marked where you can walk in and look at them.
- Before the inspection, ask which city issues this permit and who schedules it. Ask who carries the re-inspection fee if it fails. Flower Mound’s packet states a re-inspection fee may be assessed, and lists an inspection scheduled before the work is ready as one trigger.
- Before the waterproofing gets covered, ask which system is going in, how the curb and corners are handled, and whether you can have photographs.
- Before final payment, ask which inspections closed this permit, and ask to see them.
Plumbing in Texas is licensed by the Texas State Board of Plumbing Examiners, whose consumer sheet states that “Licensed or Registered plumbers in Texas are required to carry their license cards with them while on a job site.” Asking to see one on the day your drain gets moved is normal.
Sources
- Town of Flower Mound, Residential Construction Information Packet. The inspection and concealment rule, plumbing rough and top-out as separately scheduled inspections, testing of tubs, shower liners and receptors at top-out, exhaust ducts terminating outside, the second fan rule, GFCI in wet locations, re-inspection fees. The packet is written for new residential construction, so this guide leans on its general concealment rule instead of treating its inspection list as a remodel’s.
- Town of Flower Mound Building Inspections. Adopted 2024 IRC and 2023 NEC, effective 10.1.2025.
- Building America Solution Center, U.S. Department of Energy. The 50 cfm and 20 cfm exhaust rates, and venting outdoors.
- U.S. EPA, A Brief Guide to Mold, Moisture and Your Home. The 24 to 48 hour drying window.
- U.S. EPA WaterSense, bathroom faucets. The 1.5 and 2.2 gallons per minute flow rates.
- Texas State Board of Plumbing Examiners, Always Hire a Licensed Plumber. License cards on a job site.
Nothing above tells you how long your bathroom will take or what your contractor will charge. Both turn on scope, foundation type, and your city’s inspection calendar, and neither could be sourced honestly.
Sources
- Residential Construction Information Packet Town of Flower Mound, Texas
- Building Inspections, adopted codes list Town of Flower Mound, Texas
- Bathroom Exhaust Fans resource guide Building America Solution Center, U.S. Department of Energy
- A Brief Guide to Mold, Moisture and Your Home U.S. Environmental Protection Agency
- WaterSense: Bathroom Faucets U.S. Environmental Protection Agency
- Always Hire a Licensed Plumber consumer sheet Texas State Board of Plumbing Examiners
Common questions
How long does a bathroom remodel take?
There is no honest single number, and any page that gives you one without asking about your house is guessing. What the answer turns on is whether the layout changes. A bathroom that keeps every drain where it is runs demolition, rough-in, inspection, waterproofing, tile, then finishes with no detours. Move a drain in a slab-on-grade house and you add a whole phase in front of that: cutting the slab, trenching, re-plumbing, an inspection while the trench is open, then patching concrete and letting it dry. Two other waits are built into the job, and neither one means the crew is slow. The first is the inspection, because nothing can be covered until it is approved. The second comes at the very end, because shower glass is normally measured after the tile is set, so it gets ordered at the point the room already looks finished. Ask your contractor for a schedule with the inspection dates and the glass lead time marked separately from the labor days, and the timeline stops feeling arbitrary.
What is a rough-in inspection, and what happens if it fails?
Rough-in is all the work that will be invisible once the walls close: supply lines, drain and vent, the shower valve body, the exhaust duct, circuits, and the blocking inside the wall. The inspection is the city looking at all of it while it is still exposed. The Town of Flower Mound states the principle in its residential construction packet: construction or work for which a permit is required is subject to inspection, and that work has to remain accessible and exposed for that purpose until approved. If it fails, the correction gets made and the inspector comes back. Nothing that would cover the work can go ahead in the meantime, so drywall, backer board, tile, and every trade behind them wait. Flower Mound's packet also states that a re-inspection fee may be assessed, and lists an inspection scheduled before the work is ready as one of the triggers. Ask about that before you sign, because most contracts are silent on who carries a re-inspection fee, and the answer tends to get decided in the moment otherwise.
What is a shower pan test and should I be there for it?
It is the simplest test on the whole job and the one a homeowner can most easily follow. The drain is plugged, the shower pan or liner is filled with water, and everybody waits to see whether the level drops or anything shows up below. Flower Mound requires it at plumbing top-out wherever tubs and shower liners are installed, stating that all tubs, shower liners, and receptors shall be tested at that inspection. Whether it appears on your remodel permit depends on your city and your scope, so ask which inspections are on your list before demolition starts. If it is on there, be home for it. It is the one moment in the project where somebody with no construction background can stand in the doorway and genuinely verify something. What it verifies is the only layer in the room whose failure you would not discover for years.
Can I move my shower or toilet if my house is on a slab?
Yes, and it is a different job from what most homeowners picture. In a slab-on-grade house the drain lines are cast into the concrete or run beneath it, so moving a toilet, a shower drain, or a tub waste more than a few inches means cutting the slab open, trenching, re-plumbing, getting that work inspected while the trench is still open, then patching the concrete back and letting it dry. None of that is difficult work, but it is a separate phase with its own inspection sitting in front of everything else in the schedule. In a pier-and-beam house those same lines hang below the floor joists, so the same change is a day spent under the house instead. Two constraints apply either way: drain lines need continuous fall toward the main, and the vent has to go somewhere, which is why a wall you assumed was empty sometimes cannot come out. Ask your contractor whether the slab work is a specified line item in the quote or a placeholder, because that single line is often what separates two bids on the same bathroom.
What usually gets found when a bathroom is opened up?
A bathroom hides more in a small footprint than any other room in the house, and the first two days of demolition are when the job learns what it really is. The recurring finds are a subfloor gone soft around the toilet flange from a wax ring that has been weeping quietly for years, a shower pan that was never really a pan, a cast iron or galvanized drain line that is sound in places and scaling shut in others, the vent stack sitting in the exact wall you wanted to open, framing that is no longer square because the house moved on clay soil, and bathroom wiring with no ground. None of that means you were quoted badly, because nobody can quote what they cannot see. It does mean that the paragraph in your contract about how a discovery gets billed is the most important paragraph in the document, and it is worth settling before demolition day rather than on it, when the wall is open and your leverage is lower.
Do I need a permit to remodel a bathroom in Dallas-Fort Worth?
If you are moving plumbing, adding or changing wiring, or altering walls, assume yes and confirm with your own city. Permits are issued by the city rather than the state, and Flower Mound, Southlake, Colleyville, Keller, Arlington, Fort Worth, and Dallas each run their own building department, their own inspection list, and their own adopted code editions. Flower Mound, for instance, lists the 2024 IRC and the 2023 NEC among its adopted residential codes, effective 10.1.2025, and a neighboring city may sit on a different edition entirely. That is why a contractor who says no permit is needed should be able to say why in a sentence, referring to your specific city. The consequence of skipping one is rarely immediate. It usually surfaces years later at resale, when an inspector or a buyer's lender asks about work that has no record, and by then it is the homeowner's problem, not the contractor's.
Can I use the bathroom while it is being remodeled?
No, not from demolition through final inspection. The fixtures come out on day one and the toilet does not go back until after tile, so plan on the room being unusable for the whole run instead of for a few days. If it is your only bathroom, that changes the project instead of merely inconveniencing you, so say so before anyone quotes. Two questions are worth putting to the contractor before the crew arrives. First, which days the water will be shut off to the whole house, not just to that bathroom, because re-plumbing and any slab work will require it. Second, whether the crew needs access to a working bathroom on site, since a house with its one bathroom under demolition does not have one. Get both answers into the written schedule before anyone starts, and you can plan around the shutoff instead of finding out about it at seven in the morning.
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