Bathroom Plumbing in Walnut Creek: Toilet, Faucet and Shower Valve Repair
We handle bathroom plumbing in Walnut Creek from the small stuff to the big jobs: running toilets, leaks at the toilet base, dripping faucets, shower valves that scald or won't shut off, slow drains, and new high-efficiency toilets, sinks and ADA fixtures. We've worked on Walnut Creek bathrooms since 1993, including plenty of original mid-century ones and aging-in-place upgrades in Rossmoor. A real person answers 24/7, estimates are free, and seniors get a discount. Call (925) 887-6347 and tell us what's going on.
- Open 24 hours, including holidays
- Licensed and insured since 1993
- Written price before any work starts
- Senior discount available
Bathroom plumbing in Walnut Creek: what we fix and install
We repair and install toilets, faucets, sinks, tub and shower valves, ADA fixtures and the drain, waste and vent piping behind them, for homes across Walnut Creek and the rest of Contra Costa County. If water is running where it shouldn't, or not running where it should, in your bathroom or laundry room, that's our work.
Bathrooms take more daily abuse than any other room in the house. A toilet gets flushed thousands of times a year, a shower valve gets cranked hot and cold twice a day, and the drains carry hair, soap, toothpaste and whatever else ends up in them. Most of what we see is ordinary wear. A good share of it, though, is mid-century plumbing that has simply reached the end of its life.
Toilet repair and installation
Running toilets, weak flushes, rocking bowls, leaks at the base, cracked tanks, and new high-efficiency low-flush toilets set on a fresh wax ring or seal with a properly anchored flange.
Faucets and sinks
Dripping lavatory faucets, worn cartridges, loose handles, new faucets, pedestal and vanity sinks, undermount and vessel sinks, plus the shutoff valves and supply lines under them.
Tub and shower valves
Shower valve repair and replacement, scalding or cold surprises, drips from the spout, stuck diverters, and new pressure-balancing or thermostatic valves during a remodel.
ADA and aging-in-place fixtures
Comfort-height toilets, lever handles, hand-held showers on slide bars, wall-hung or open-front sinks and other ADA-compliant installations for people who want to stay safely in their homes.
Drain, waste and vent (DWV)
The hidden piping that carries water away and lets sewer gas vent through the roof: slow drains, gurgling, sewer smells and replacing old cast iron or galvanized drain lines.
Fixture selection advice
Help choosing toilets, faucets and valves that fit your rough-in, your water, your budget and how you actually use the room, before you buy something that won't fit.
We also handle laundry rooms, which share a lot of the same plumbing: washing machine boxes, hookups and laundry sinks. That's covered in the faucet and sink section below.
Signs your bathroom plumbing needs a plumber
The short answer: call when water shows up somewhere it shouldn't, when a fixture won't shut off, or when a drain or toilet backs up more than once. The table below sorts the common symptoms by what they usually mean and how fast you should act.
| What you notice | What it usually means | How urgent |
|---|---|---|
| Toilet runs on its own or refills every few minutes | Worn flapper, fill valve or flush valve seal letting tank water leak into the bowl | Soon. It wastes water around the clock. |
| Water on the floor around the toilet base | Failed wax ring or seal, cracked flange, loose closet bolts or a cracked bowl | Soon. Hidden leaks rot subfloors. |
| Toilet rocks when you sit on it | Loose bolts or a broken flange; often the first step toward a base leak | Soon |
| Shower water suddenly scalds or turns cold when someone flushes | Older valve without pressure balancing, or a worn balancing cartridge | Soon, especially with children or older adults in the home |
| Tub spout drips after the shower is off | Worn valve cartridge, stem washers or seats | Moderate |
| Slow sink or tub drain | Hair and soap buildup in the trap or drain line; sometimes a vent problem | Moderate |
| Gurgling drains or a sewer smell | Dry trap, blocked vent or a damaged drain line | Soon. Sewer gas does not belong indoors. |
| Water stain on the ceiling below a bathroom | Leaking shower pan, valve, drain or supply line | Right away. Shut off water to that fixture if you can. |
| Toilet overflowing or several fixtures backing up at once | A blockage in the main drain or sewer lateral | Right away. Stop using water and call. |
If several drains in the house are slow or back up together, the problem probably isn't in the bathroom at all. That points to the main line, and our drain cleaning or sewer line repair pages explain what happens next.
Why Walnut Creek bathrooms have the problems they do
A lot of Walnut Creek's housing went up in a hurry in the 1950s and 1960s, and many bathrooms still have original pipes hidden behind updated tile. The city grew from 9,903 people in 1960 to 39,844 in 1970, and much of that building boom is still standing in neighborhoods like Parkmead, Larkey Park, Walnut Heights and Rancho Paraiso.
Galvanized supply lines and cast iron drains
Homes from that era often have galvanized steel water lines, which corrode from the inside. The pipe slowly closes up, so you get low pressure at the shower, rusty water after a vacation, and leaks at threaded joints. Drains were commonly cast iron, which can crack or rust through along the bottom of the pipe where water sits. When we open a wall to replace a shower valve, we look at what's around it and tell you honestly whether those pipes have years left or should be replaced while the wall is open. If they're done, our water line and repiping team can take it from there.
Your water district matters for fixtures
Walnut Creek is split between two water suppliers, and which one you have depends on your address. East Bay MUD water is soft, in the range of 1 to 7 grains per gallon, so it's fairly easy on faucet cartridges and toilet fill valves. Contra Costa Water District draws mainly from the Delta through the Contra Costa Canal, and its quality changes with the season, with higher salinity in summer. Neither is bad water, but it is worth knowing which one you have when we talk about cartridges, aerators and how often parts wear out.
Long ownership, original fixtures
Many owners have been in their homes for decades. Long ownership is common in California, and it often means the toilets, valves and shutoffs are the same ones that came with the house. That's fine until the day a shutoff valve under the sink won't turn, or crumbles when it does. We replace those as a matter of course when we work on a fixture, because a shutoff that doesn't shut off is no help in an emergency.
Toilet repair and high-efficiency toilet installation
Most toilet problems are fixed with parts inside the tank, and we'll always tell you if a repair makes more sense than a new toilet. When the bowl is cracked, the toilet is very old, or parts aren't available, replacing it with a high-efficiency model is usually the better call.
Common toilet repairs
- Replacing flappers, fill valves and flush valves so the tank stops running
- Fixing weak or double flushes by adjusting water level and checking the rim jets
- Resetting a leaking or rocking toilet on a new wax ring or wax-free seal
- Repairing or replacing broken closet flanges so the toilet is held tight to the floor
- Replacing tank-to-bowl gaskets and bolts that weep onto the floor
- Clearing toilet clogs with the right auger, without scratching the bowl
- Replacing the angle stop and supply line so you can shut the water off when you need to
California's high-efficiency toilet rules
California Health and Safety Code section 17921.3 requires that, on and after January 1, 2014, toilets other than institutional ones be high-efficiency models. The law defines a high-efficiency toilet as one with an effective flush volume of no more than 1.28 gallons, whether it is single flush or dual flush. So any new toilet we install meets that standard.
People sometimes worry that a low-flush toilet means double flushing. Older early-generation low-flow toilets earned that reputation. Today's models are designed around the lower water volume, and fixture selection is where the difference shows up. We'll talk with you about bowl shape, height, flush style and how your drain line is pitched, because a toilet that suits the house will flush better than one picked only for its looks.
Selling your house: the water-conserving fixture law
California Civil Code sections 1101.1 and following, passed as SB 407, apply to homes built and available for use on or before January 1, 1994. That covers most of Walnut Creek. Under the law, a noncompliant fixture is a toilet made to use more than 1.6 gallons per flush, a urinal over 1 gallon per flush, a showerhead over 2.5 gallons per minute, or an interior faucet over 2.2 gallons per minute.
For single-family homes, owners were required to replace noncompliant fixtures on or before January 1, 2017, and a seller must disclose in writing to the buyer the replacement requirement and whether the property has noncompliant fixtures. Multifamily and commercial properties had a January 1, 2019 deadline with their own disclosure rules. The law also makes replacing noncompliant fixtures a condition of final permit approval for many alterations and improvements. There are limited exceptions, including when a licensed plumber certifies that installing water-conserving fixtures isn't technically feasible.
If you're getting ready to sell, call us. We can check every toilet, showerhead and faucet in the house and replace the ones that don't comply, so your disclosure is straightforward. Your agent or the permit office can tell you exactly what paperwork your sale needs.
Faucet, sink and laundry hookup repair and installation
A dripping bathroom faucet is almost always a worn cartridge, washer or seat, and it's usually a quick repair if parts are available. If the faucet body is corroded, the finish is failing or parts are discontinued, a new faucet is often the smarter spend.
When we replace a faucet, we look at everything under the sink: the shutoff valves, the supply lines, the drain tailpiece and the P-trap. A new faucet on old, stiff supply lines is just moving the leak somewhere else. We also make sure the pop-up drain works, the trap is sealed, and nothing drips when the cabinet doors close on it.
Sinks we install
A tip from experience: before you buy a new vanity or faucet, check the hole pattern in your countertop and the space behind the sink. A widespread faucet won't go on a single-hole sink, and a vessel sink needs a taller faucet or a wall-mount spout. Call us with the model numbers and we'll tell you if it'll work before you open the box.
Laundry room plumbing: washer boxes, hookups and laundry sinks
We install and repair washing machine boxes, washer hookups and laundry sinks and faucets. A washer box is the recessed panel in the wall that holds the hot and cold valves and the drain standpipe, and it keeps everything tidy and accessible.
- New or replacement washing machine boxes with fresh valves and a proper drain connection
- Washer hookups when you move the laundry to a new room or garage
- Laundry sinks and faucets, including utility tubs in the garage
- Replacing stuck or leaking washer valves
- Tracking down leaks behind and under the machine
- Dryer gas hookups and gas conversions, covered on our gas lines and piping page
A practical tip: look at your washer hoses. Rubber hoses get brittle with age and can split under pressure. Braided stainless hoses are a common upgrade. If you'll be away for a while, turning off the washer valves is a cheap bit of insurance.
Shower valve repair and tub/shower valve replacement in Walnut Creek
If your shower drips, won't hold a steady temperature, or the handle is stiff or loose, the valve cartridge or stem is usually worn and can often be replaced without opening the wall. If the valve body itself is failing, or you want a different style, replacing the valve means opening the wall or working through an access panel.
Shower valve repair starts with identifying the brand and model, which isn't always easy on a valve that's been in the wall since the 1960s. We look at the trim, pull the handle, and check the cartridge. Many valves from major brands still have parts. Some older two-handle and three-handle valves use stems and seats that can be rebuilt. When they can't, we'll show you why.
Pressure-balancing vs thermostatic valves
A pressure-balancing valve keeps the hot and cold mix steady when someone flushes a toilet or starts the washer. A thermostatic valve holds a set water temperature and usually lets you control volume separately. Both prevent the sudden scald or cold blast that older single-control valves were known for.
| Option | Best for | Trade-offs |
|---|---|---|
| Replace the cartridge only | Valve body is sound and parts are available | Least disruption; trim stays the same |
| New trim kit on existing valve | You want a new look and the valve is from a brand that offers compatible trim | Limited to that brand's styles |
| New pressure-balancing valve | Old valve is failing or not repairable | Requires wall access; tile work may be needed |
| New thermostatic valve | Remodels, households with kids or older adults who want precise temperature | Typically more parts and more setup |
Replacing a valve is a good moment to check the shower arm, the tub spout, the drain and the overflow, and to look at the pipes feeding the valve. If they're galvanized and you're opening the wall anyway, it often makes sense to change them at the same time.
ADA fixtures and aging-in-place bathrooms, including Rossmoor
We install ADA-compliant fixtures and simpler aging-in-place upgrades so a bathroom stays safe and easy to use as needs change. Taller toilets, lever handles, hand-held showers and easy-reach controls make a real difference, and many of them can be done without a full remodel.
Rossmoor is the clearest example in Walnut Creek. The community was built from 1963 in the Tice Creek Valley, is home to about 9,800 residents in 6,676 homes, and is a 55-plus community managed by the nonprofit Golden Rain Foundation. Most homes are co-ops and condos, and many are in garden-style buildings of two to four units or in mid-rise and high-rise buildings. That means a lot of bathrooms that are decades old, pipes shared with neighbors, and owners who want the room to keep working for them for years.
Comfort-height toilets
A taller bowl is easier to sit down on and stand up from. We match the toilet to your rough-in so it fits the existing drain.
Lever handles and single-control faucets
Easier for hands with arthritis or limited grip than round knobs. A simple swap in most bathrooms.
Hand-held showers and slide bars
Let you shower seated and aim the water where you need it. We mount them where you can reach them comfortably.
Safer shower valves
Pressure-balancing or thermostatic valves help prevent scalding, which matters more as reaction time slows.
In Rossmoor and other condo or co-op buildings, plumbing in walls and floors may be shared between units, and your mutual or homeowners association may have rules about who can work on it and when. Before we schedule, check with your building manager or board. We're happy to talk with them about the scope of the job.
Grab bars and wall reinforcement are usually carpentry rather than plumbing, so if your project needs them we'll say so and work around that trade. Our part is getting the fixtures and valves right. For the rest of the house, a whole-house plumbing inspection is a sensible starting point.
Drain, waste and vent systems behind the bathroom
Every sink, tub, shower and toilet connects to a drain line that carries water away and a vent that lets air in and sewer gas out through the roof. When drains are slow, gurgle or smell, the trouble is often in that DWV system rather than the fixture itself.
Each fixture has a trap, a bend that holds water and blocks sewer gas. A P-trap under a sink is the one most people know. If a fixture isn't used for weeks, like a guest bathroom shower, the water in the trap can evaporate and let sewer odors in. Running water for a minute usually fixes it. If the smell comes back quickly, there may be a vent problem or a leak in the drain.
Vents matter more than most people think. A blocked vent can make a toilet flush poorly, cause sinks to drain with a glugging sound, or siphon traps dry. Older homes sometimes have vent configurations that wouldn't pass today, and remodels sometimes cut vents without replacing them properly.
When drain lines themselves are failing, we can replace sections of old cast iron or galvanized drain pipe with modern piping during a remodel or as a repair. For a closer look at what's inside, we use inline drain and sewer video inspection so we're not guessing. Leaks under floors or in walls can also be tracked down with our electronic leak detection.
How a bathroom plumbing visit works
You call, a real person answers, and we get a technician to your home to look at the problem and give you a written price before any work starts. Here's what that looks like step by step.
- You call (925) 887-6347Tell us what's happening: the fixture, the symptom and how long it's been going on. We'll tell you if there's anything to do right away, like closing a shutoff valve.
- We set an arrival windowWe schedule a time that works for you and let you know when the technician is on the way. We're open 24/7 for problems that can't wait.
- Diagnosis at the fixtureWe find out what's actually wrong: worn part, failed seal, clogged drain, vent issue or something in the wall. We'll show you what we found.
- Written price firstYou get a clear written price and your options, such as repair vs replace, before work begins. Estimates are free.
- The workWe protect floors, shut off water to the area, and do the repair or installation with quality parts. Shutoff valves and supply lines get checked or replaced as needed.
- Test and clean upWe run every fixture we touched, check for leaks, show you how things work and leave the bathroom clean.
Permits, cost and fixture selection advice
Simple repairs like replacing a flapper, a cartridge or a faucet usually don't need a permit. Bigger jobs, such as moving drains, adding fixtures or remodeling, generally do. Inside city limits, permits go through the City of Walnut Creek planning and building office at 1666 North Main Street, (925) 943-5800. Unincorporated areas like Saranap use Contra Costa County.
What affects the price
- Repair vs replacement, and whether parts for your fixture are still available
- Access: an open vanity vs a valve behind tile with no access panel
- The condition of the pipes, shutoffs and flange we find when we open things up
- The fixture you choose, and whether you supply it or we do
- Whether a permit is needed for the job
- After-hours emergency timing
Estimates are free, and we offer a senior discount. We accept Mastercard and Visa.
Fixture selection advice before you buy
Fixture selection advice is one of the services we offer, and it saves a lot of returns. A few things we check: the toilet rough-in (the distance from the wall to the drain), the valve brand behind your shower, the countertop hole pattern, and whether a fixture uses a cartridge you can get locally. We can also tell you which parts tend to hold up in your water.
Bathroom plumbing you can safely do yourself, and when to call
Some bathroom fixes are fine for a handy homeowner. Others are easy to make worse. Here's where we draw the line.
Usually fine to do yourself
Plunging a toilet with a flange plunger. Cleaning a faucet aerator. Pulling hair out of a pop-up or tub drain. Running water in an unused shower to refill the trap. Replacing a flapper if you're comfortable with it. Learning where every shutoff valve is.
Better to call a plumber
Anything that involves opening a wall, replacing a shower valve, moving a drain, setting a toilet on a damaged flange, or a shutoff that won't turn. Also any leak showing up on a ceiling below, and repeated clogs.
One more habit worth having: don't flush wipes, even ones labeled flushable. Central San, which handles sewer service in Walnut Creek, lists wipes among the causes of sewer blockages. Toilet paper and human waste only.
Why Walnut Creek calls us for bathroom plumbing
We're a family business that has served Contra Costa and Alameda Counties since 1993, working out of our North Main Street shop. Owner Mo Williams grew up in the Bay Area and learned plumbing and construction products and installation at Simon's Hardware in Walnut Creek and Home Depot in Concord, so fixture selection is in his background.
We're a California licensed C-36 plumbing contractor, licensed and insured, open 24/7, and a real person answers the phone. Our Google rating is 4.7 from 251 reviews as of October 2026. One customer said Kevin solved their problem and fixed their water leak in a timely manner, which is the kind of review we like best. Planning a bigger project? See our kitchen plumbing page too.
A family business led by Mo Williams since 1993
We are a Walnut Creek family business run from our North Main Street shop. Owner Mo Williams grew up in the Bay Area and learned plumbing products and installation from the inside out at Simon's Hardware in Walnut Creek and Home Depot in Concord. His wife Ann runs the books as CFO. We're rated 4.7 on Google from 251 reviews (October 2026). Meet Mo
Frequently asked questions
How much does toilet repair cost in Walnut Creek?
Toilet repair cost depends on what's wrong, so we give you a free written estimate after we look at it. A worn flapper or fill valve is a smaller job than resetting a toilet on a broken flange or replacing the toilet entirely. Access, parts availability and whether it's an after-hours call also matter. We offer a senior discount and accept Mastercard and Visa. Call (925) 887-6347 to describe the problem and set up a visit.
Should I repair or replace my old toilet?
Repair makes sense when the bowl and tank are sound and parts are available, which covers most running and leaking toilets. Replacement makes sense when the porcelain is cracked, parts are discontinued, the toilet clogs often, or it is an older model that uses more than 1.6 gallons per flush. New toilets sold or installed in California must be high-efficiency models using no more than 1.28 gallons per flush.
Why does my shower suddenly get hot or cold?
A sudden temperature swing usually means your shower valve can't balance pressure when someone uses water elsewhere in the house, like flushing a toilet. Older single-control valves often lack pressure balancing, and newer ones can have a worn balancing cartridge. Replacing the cartridge or upgrading to a pressure-balancing or thermostatic valve fixes it. This matters most in homes with young children or older adults, who are more at risk from scalding.
Can you repair a shower valve without opening the wall?
Often, yes. If the valve body is sound and parts are available, we can usually replace the cartridge or rebuild the stems from the front after removing the handle and trim. If the valve body is cracked, corroded or obsolete, or you want a different valve type, replacing it means opening the wall or working through an access panel. We'll tell you which situation you're in before any work starts.
Do I have to replace old toilets before selling my house in California?
California Civil Code 1101.1 and following, from SB 407, cover homes built on or before January 1, 1994. Single-family owners were required to replace noncompliant fixtures, such as toilets using more than 1.6 gallons per flush, by January 1, 2017, and sellers must disclose in writing whether noncompliant fixtures remain. We can check and replace fixtures before you list. Your agent can confirm the paperwork for your sale.
Do you install ADA fixtures in Rossmoor?
Yes. We install ADA-compliant and aging-in-place fixtures throughout Walnut Creek, including Rossmoor, such as comfort-height toilets, lever-handle faucets, hand-held showers and safer pressure-balancing or thermostatic shower valves. Because many Rossmoor homes are co-ops or condos with shared plumbing, check with your mutual or building manager about any rules first. We offer free estimates and a senior discount.
Why does my bathroom smell like sewer gas?
The most common cause is a dry trap in a fixture that isn't used often, like a guest shower or floor drain. Running water for a minute refills the trap and usually stops the smell. If it comes back, the cause may be a blocked vent, a loose toilet seal, or a cracked drain line. Sewer gas shouldn't be in your home, so call if the odor keeps returning.
Do you hook up washing machines and laundry sinks?
Yes. We install and repair washing machine boxes, washer hookups, laundry sinks and laundry faucets, and we track down leaks around laundry equipment. If you're moving the laundry to a new location, we can run new supply and drain lines. Dryer gas hookups and conversions from electric to gas are handled by our gas line team. Call (925) 887-6347 for a free estimate.
Do I need a permit for bathroom plumbing work in Walnut Creek?
Simple repairs like replacing a cartridge, flapper or faucet generally don't need a permit. Remodels, moving or adding fixtures, and changes to drain or vent piping generally do. Inside city limits, permits go through the City of Walnut Creek building office at 1666 North Main Street, (925) 943-5800. Unincorporated areas such as Saranap go through Contra Costa County. We'll tell you whether your job needs one.
Can you help me choose a new toilet or faucet?
Yes, fixture selection advice is one of our services. Before you buy, we check your toilet rough-in, countertop hole pattern, shower valve brand and available space so the new fixture actually fits. We'll also tell you which models have parts that are easy to get later. Call us with the model numbers you're considering and we'll give you a straight answer.
Other ways we help Walnut Creek homes
Call a Walnut Creek plumber for bathroom plumbing
A real person answers 24 hours a day, 7 days a week. Tell us what's happening and we'll give you an honest arrival window and a free written estimate before any work starts.
Call now, day or night
(925) 887-6347- Licensed plumber, not a salesperson
- Free written estimate before work begins
- Senior discount, ask when you call
- Mastercard and Visa accepted
- Non-urgent questions: balzaparis@gmail.com
Water or sewage spreading? Shut off the fixture or main valve, then call. Smell gas? Leave first and call PG&E at 1-800-743-5000 or 911 from outside.
2108 N. Main Street, Suite F
Walnut Creek, CA 94596
Phone: (925) 887-6347
Email: balzaparis@gmail.com
Open 24 hours, 7 days a week