Plumbing Rough-In Services in San Antonio, TX
Plumbing rough-in is the piping stage that happens before walls, floors and finished fixtures. Stark Plumbing Solutions installs underground, supply and drain-waste-vent rough-in for new homes, additions and remodels in San Antonio, then tests it and gets it through inspection before anything is covered.
What Is Plumbing Rough-In?
Plumbing rough-in is the installation of all the pipes you will never see again once the house is finished. It includes the underground drain lines under the slab, the water supply lines running to each fixture location, and the drain-waste-vent (DWV) pipes that carry water away and let air in. It is called “rough” because fixtures like toilets, faucets and sinks are not installed yet. Pipes are stubbed out at the exact locations where those fixtures will go.
If you are searching “what is rough-in plumbing,” you probably want three things: what is included, when it happens, and what it should cost. Here is the short version.
- What: Underground, supply and DWV piping, plus shower and tub valves, installed before walls close.
- When: Before the slab is poured and again before insulation and drywall.
- Cost: Often starting around $1,600 per bathroom in San Antonio, rising with fixtures, distance, slab cutting and materials.
Rough-in versus finish-out
| Rough-in | Finish-out (trim) | |
|---|---|---|
| --- | --- | --- |
| Timing | Before walls, floors, slab | After paint, tile, cabinets |
| Work | Pipes, vents, valves | Toilets, sinks, faucets, trim |
| Visibility | Hidden once covered | Visible daily |
| Inspection | Required before cover | Final check |
| Change cost | Low before closing, high after | Moderate |
Rough-in is a construction-stage service. It is different from repair work such as water line repair or leak detection, which fix pipes in a finished home.
Underground Rough-In Plumbing
The ground phase happens before concrete. We trench, lay the main drain and branch drains, set the sewer connection, and stub up every line at the fixture locations shown on the plans.
What must be right underground
- Slope: Drain lines need a consistent fall toward the sewer. A low spot, or “belly,” collects waste and causes chronic clogs.
- Location: Stub-ups must land within the wall or fixture footprint. Off by a few inches can mean moving a toilet flange after the pour.
- Bedding and protection: Rock, caliche and clay all stress pipe differently. We bed and sleeve pipe so movement does not crush or crack it.
- Cleanouts: Access points must remain reachable after finished floors and landscaping.
- Testing: The underground system is tested before it is buried and before the slab is poured.
If your project is a full new home, see our new construction plumbing page.
Water Supply Pipe Rough-In
Supply rough-in brings hot and cold water to every fixture, appliance and hose bib. We size pipe for the flow each fixture needs, plan shutoff locations, and run lines with enough support to prevent noise and movement.
Choosing pipe material
- PEX: Flexible, quick to install, good freeze tolerance, fewer joints.
- Copper: Proven and durable, higher material cost, great where heat or UV exposure is a concern.
- CPVC: Common in homes built in the 2000s. Works when installed correctly, but older systems can become brittle, so inspectors and buyers ask about it.
Design decisions that save headaches
- Place shutoffs where you can reach them
- Insulate supply lines in exterior walls and attics
- Plan for a recirculation loop if you want fast hot water. See hot water recirculation pumps.
- Add a pressure regulator if street pressure is high
- Leave blocking in walls for grab bars, pot fillers and wall-mount faucets
Tub and shower valves
We set rough-in valves at the correct depth for your tile thickness and match them to the trim you chose. Local rough-in prices for shower valves and kits are modest, but a mismatched valve means opening finished walls.
Drain-Waste-Vent Rough-In
Drains work by gravity, and vents let air in so water can flow. Together, DWV piping is the part of a plumbing system most often done wrong by rushed or unlicensed installers.
Common DWV mistakes
- Insufficient slope, which causes slow drains and clogs
- Missing or undersized vents, which cause gurgling and sewer gas smell
- Improper fittings, such as flat-turned wyes where long-sweep fittings are needed
- Wrong trap arms, which let siphoning pull water out of traps
- No cleanout access, which turns a simple clog into a major repair
How we install DWV
Every branch drain gets code-based sizing and slope. Vents tie in at proper heights and exit through the roof with correct flashing. We keep runs as straight as the structure allows and support them so they do not sag over time.
Kitchen and Bathroom Rough-In Work
Bathroom rough-in
Each bathroom needs supply stubs for toilet, sink and tub or shower, drains for each fixture, a vent system and a shower or tub valve. Primary bathrooms with double vanities, freestanding tubs or multiple shower heads add drains, supply runs and sometimes extra venting.
Kitchen rough-in
Kitchens need supply and drain for the sink, dishwasher and disposal connections, an ice-maker or refrigerator water line, and sometimes a pot filler or gas line. Islands are a special case. An island sink needs its own vent solution because the pipe cannot rise through a wall. See our kitchen remodel plumbing page for details.
Laundry and utility
Laundry boxes need a standpipe drain with proper trap and vent, and shutoff valves. Water heater locations need supply, relief valve drain and gas or electrical coordination.
Outdoor connections
Hose bibs, outdoor kitchens and irrigation tie-ins are best planned during rough-in. Freeze-protected hose bibs avoid cold-weather damage.
Pressure Testing and Inspections
Testing and inspection are what separate a clean rough-in from a hidden problem. Here is the usual sequence.
Visual check
We review all runs, fittings, supports, slopes and fixture locations against plans.
Supply pressure test
The water supply system is pressurized and held to confirm there are no leaks at joints.
Drain and vent test
The DWV system is tested with water or air as required by the adopted code to prove it is tight.
Photo documentation
We photograph rough-in before it is covered, which helps with inspections, warranties and future repairs.
City inspection
A permit-required rough-in must pass inspection before insulation, drywall or concrete covers it.
Release to next trade
Once approved, framers, insulators and drywall crews can proceed.
When is plumbing inspected before walls are closed?
For new construction, the City of San Antonio requires top-out plumbing, along with gas rough-in, mechanical, electrical rough-in and framing inspections, to pass before the next phase can proceed. Plumbing underground is inspected before the foundation pour. Remodels that involve permitted plumbing follow similar rules for exposed work. We confirm requirements for your scope and schedule inspections.
Which rough-in stage is your project in?
Pick your stage. We will show what to do now and what to avoid.
Tap an option above to see what it involves.
Rough-In Readiness Checklist
Run through this before your plumber arrives for rough-in.
What Rough-In Costs and Where Projects Go Wrong
Cost drivers
Bathroom count, fixture count, distance from the main drain, slab cutting, materials and accessibility all drive price. A typical San Antonio rough-in can start around $1,600 per bathroom, while shower valves and kits themselves run roughly $50 to $100 depending on brand. Whole-home figures vary, so we recommend itemized quotes.
Where projects go wrong
- Late fixture changes after rough-in, causing rework
- Unpermitted work that fails city inspection or an insurance review
- Covered before inspected, forcing tear-out
- Wrong or missing vents, causing slow drains and odors
- Pipes pinned or unsupported, causing noise or leaks
- Verbal quotes that change once the job starts
How we handle it
Written scope, per-bathroom pricing, change-order approval before extra work, photos before cover, and no cover-up until inspected.
San Antonio Seasons and Rough-In Timing
Winter: Plan insulation of exterior-wall supply lines and freeze-protected hose bibs. Rough-in is the ideal time to route pipes away from the coldest spots. Learn more about frozen pipe repair.
Spring and fall rain: Wet trenches and muddy sites delay ground phase. Keep stub-ups capped so debris does not enter lines.
Summer heat: Fast curing concrete and hot attics affect scheduling. Attic rough-in is best in early morning.
Drought and shifting soil: Clay contracts and slabs move. Proper sleeves and support guard against stress-related leaks later.
What Homeowners and Builders Ask About Rough-In
“Can I add a bathroom later?”
Yes, but it is far cheaper to rough it in during construction. Adding a bathroom to a finished slab home means cutting concrete and tying into the main drain. If you may want a future half-bath or wet bar, ask us to stub in drain and supply now.
“Do I need rough-in for a garage or casita?”
If you might add a utility sink, laundry or ADU later, planning a stub-out saves tear-out. We can rough in capped lines for future use.
“Why does the plumber need fixture model numbers so early?”
Because rough-in dimensions depend on them. Toilet rough-in distance (commonly 12 inches), shower valve brand and depth, and tub drain offsets all vary. A mismatch means moving lines.
“What is top-out?”
Top-out is the rough-in stage after framing, when supply, drain and vent lines run through walls and exit the roof. It is also called the in-wall or second rough-in phase.
“What if framers or electricians cut my pipes?”
It happens when trades work in the same space. We photograph rough-in, mark critical runs and test again after other trades finish if there is any doubt.
“Is rough-in the same for every home?”
No. Slab, pier-and-beam, multi-story, and metal-roof homes each need different routing and vent solutions.
How to Choose a Rough-In Plumber in San Antonio
Local search results are crowded with plumbers, and Facebook and Reddit threads are full of warnings. Here is how to filter.
Verify before you trust
- Texas plumbing license status for the responsible plumber
- Proof of insurance
- Reviews that mention rough-in, not just drain cleaning
- Willingness to provide a written scope
Ask for specifics
- How do you test supply and drain systems before inspection?
- Do you schedule inspections, and how quickly do you fix failures?
- How are price changes handled?
- Can you work around other trades?
Watch for warning signs
- Large upfront cash requests
- No written scope
- Pressure to skip permits
- Quotes that ignore your plans
- A plumber who cannot explain top-out or ground phase
What we promise
Honest scope, tested work, documented rough-in and no covering before inspection. If a project is not a fit, we will say so.
Rough-in stages at a glance
| Stage | Where | Key risk |
|---|---|---|
| --- | --- | --- |
| Ground phase | Under slab | Wrong location, slope, cracked pipe |
| Top-out | Walls, attic | Cut pipes, poor vent routing |
| Remodel rough-in | Open walls | Old pipe tie-ins, hidden damage |
| Trim-out | Visible fixtures | Leaks at connections |
Materials, Code and Pipe Sizing
Pipe sizing
Pipe size determines flow and pressure. Undersized supply lines starve showers and appliances. Oversized drains can fail to carry solids. We size pipe by fixture units and code tables, not by habit.
Common materials
| Use | Typical pipe |
|---|---|
| --- | --- |
| Underground drains | PVC or ABS |
| Supply, in-wall | PEX, copper, CPVC |
| Vent | PVC or ABS |
| Gas | Black iron or approved flexible gas pipe where allowed |
Hangers, supports and protection
Pipe must be supported at regular intervals so it does not sag. We use approved hangers, nail plates where pipes pass near framing edges, and sleeves where pipes pass through concrete.
Insulation and noise
Drain pipe in walls can carry sound. Wrapping or using sound-damped drain pipe near bedrooms and living areas makes a noticeable difference. Supply lines should be isolated from framing so they do not tap or knock.
Future access
Leave access panels for tub valves and cleanouts. A concealed valve with no access can force you to cut tile for a repair.
Why Rough-In Is Not a DIY Project
Homeowners can help by choosing fixtures, keeping the site clear and asking for photos. The work itself belongs to professionals who can pull permits, test and stand behind it.
- Safety: Gas lines and venting errors can be dangerous.
- Code: Slope, sizing, venting and materials are regulated.
- Resale: Unpermitted plumbing complicates inspections and sales.
Plumbing Rough-In FAQs: Straight Answers for San Antonio Homeowners
What is included in plumbing rough-in?
Underground drains, water supply lines, drain-waste-vent piping, shower and tub valves, and stub-outs for each fixture, all installed before walls, floors and finished fixtures.
What is the difference between rough-in and finish-out?
Rough-in is the hidden piping installed before walls and floors close. Finish-out, also called trim-out, is the visible work after finishes, such as setting toilets, sinks and faucets.
When is plumbing inspected before walls are closed?
Underground plumbing is inspected before the slab is poured, and top-out plumbing is inspected after framing and before insulation and drywall. Remodels with permitted work follow similar rules.
How much does plumbing rough-in cost in San Antonio?
Local rough-in often starts around $1,600 per bathroom, but the real total depends on layout, slab cutting, materials and fixtures. We provide written itemized quotes.
How long does rough-in take?
Many bathrooms can be roughed in within a day or two, but whole-home projects take longer and depend on framing, weather and inspection scheduling.
Can I change fixtures after rough-in?
Sometimes, but it can mean rework. Choose fixtures and valves before rough-in to avoid delays and extra cost.
Do I need a permit for rough-in?
New rough-ins, major remodels, repiping and sewer or water line installations generally require city permits. We confirm requirements for your project.
Who schedules the inspection?
The licensed plumbing contractor typically requests plumbing inspections, coordinated with your builder or remodeler.
What if rough-in fails inspection?
We correct the issue and request re-inspection. Catching problems before walls are covered is the main purpose of inspection.
How do I get a rough-in quote?
Call (210) 898-9754 or send plans and fixture counts through our contact page.
Find Stark Plumbing Solutions
Stark Plumbing Solutions
1011 Ada St, San Antonio, TX 78223
(210) 898-9754
We rough in plumbing for projects across San Antonio, from new builds on the Northwest and Southside to remodels and additions in older central neighborhoods.
Related services:
Need rough-in done right the first time?
Send your plans or describe your project. We will give you a written rough-in scope, a realistic schedule and inspection coordination.