When there is a burst pipe in a commercial building, do three things in this order: keep people away from water near anything electrical, shut the water off at the nearest valve you can reach safely, and call the building’s emergency contact and a commercial plumber. Everything else, including finding out why it burst, can wait until the water has stopped.
If water is coming through a ceiling or across a floor right now, use the checklist below and come back to the rest later. Call (866) 981-1310 if you need a plumber on the way while you work through it.
What to do first
- Move people out of the wet area. Water near outlets, lights, panels or equipment is the immediate danger.
- Do not touch electrical equipment while standing in water. If a breaker panel can be reached from a dry spot, a responsible person can switch off the affected circuits. If it cannot, leave it.
- Shut off the water. Use the valve at the fixture if the leak is at a fixture. Otherwise use the floor, zone or main building valve.
- Call the building’s emergency contact, property manager or facilities lead, and a commercial plumber.
- Protect what you can reach safely: move stock, files and equipment, and put containers under drips.
- Take photos and video of the leak and the damage before cleanup starts.
Stopping the water is not the same as fixing the pipe
These are two separate jobs, and the first one is yours.
Stopping the water means closing a valve upstream of the break. Once that valve is shut, the damage stops growing. Most of the cost of a burst pipe comes from how long the water ran, not from the pipe repair, so every minute saved here matters more than anything a plumber does later.
The U.S. Environmental Protection Agency’s water-efficiency guidance for commercial buildings gives a sense of scale: a broken distribution line flowing at 15 gallons a minute loses 21,600 gallons in a day.
Fixing the pipe means cutting out the failed section, replacing it, and testing the line under pressure before the water goes back on. That is a plumber’s job. A clamp, tape or sealant on a pressurized commercial line is a temporary measure at best, and it can let go without warning.
Finding the right shutoff
Commercial buildings have several levels of shutoff, and most staff have never been shown any of them. That is the single most common reason a small break becomes a large loss.
| Shutoff | Where it usually is | What it stops |
|---|---|---|
| Fixture stop | Under a sink, behind a toilet, at an appliance | Water to that one fixture |
| Branch or zone valve | Above a ceiling, in a chase or utility closet | A restroom group, a kitchen, one tenant space |
| Floor or riser valve | Mechanical room, riser closet, stairwell | One floor or one vertical riser |
| Building main | Where the service enters the building, often with the backflow assembly | All domestic water to the building |
| Water meter | In a box near the street or property line | Everything, if the building main fails or cannot be found |
Use the smallest valve that stops the leak, so the rest of the building keeps its water. If you cannot find it within a minute or two, go straight to the building main.
Two warnings. First, do not force a valve that will not turn. Old gate valves can seize or snap, and a broken valve stem makes things worse.
Second, the valve at the meter may belong to the water utility, and some utilities ask customers not to operate it. In a real emergency, call the utility or the plumber and ask.
Is it a domestic pipe or a fire sprinkler pipe?
This matters, because the two systems have different valves and different rules.
Fire sprinkler piping is usually red or labeled, runs at ceiling level and feeds sprinkler heads. Its control valves are chained, locked or monitored, and closing one takes fire protection away from part of the building. Do not close a sprinkler valve unless your emergency plan or the fire department tells you to. Call the building’s fire protection contractor and the fire alarm monitoring company, because water flowing in that system normally triggers an alarm.
Domestic water piping feeds sinks, toilets, water heaters and equipment. Those valves are yours to close.
Why pipes burst in commercial buildings
Nobody can tell you the cause from the wet patch on the ceiling. The failed section has to be seen. These are the usual causes, and more than one can be in play.
Corrosion. Older galvanized steel and copper thin from the inside over decades. The pipe finally gives at its weakest point, often at a fitting or a threaded joint.
Pressure problems. A failed pressure-reducing valve lets street pressure into piping that was sized for less. Water hammer, the shock when a fast valve slams shut, stresses joints again and again.
Failed fittings and connectors. Flexible supply connectors, push-fit fittings and soldered joints all have a service life. A braided connector under a breakroom sink is a common source of weekend floods.
Freezing. Rare in Sacramento, and it does happen in unheated spaces, exterior walls and rooftop piping during a hard cold snap. Water expands as it freezes and splits the pipe, and the leak shows up when it thaws.
Accidental damage. A screw through a wall, a forklift into an exposed line, a tenant improvement crew cutting the wrong pipe.
Heat and age at water heaters. Connections and relief lines at water heaters fail more often than cold-water pipe elsewhere.
The cause decides whether the repair is one fitting or a wider problem. If one section of galvanized pipe has corroded through, the rest of that run is the same age.
What to tell the plumber
A plumber who knows what to expect brings the right material and gets to the valve faster. Have these ready when you call.
- The address, and where in the building the leak is.
- Whether the water is off, and which valve was used.
- What the pipe looks like if you can see it: copper, steel, plastic, and roughly how big.
- Whether it is hot or cold water, and whether it looks like a sprinkler line.
- What is below and around the leak: electrical rooms, server rooms, tenant spaces, stock.
- How to get in: gate codes, keys, who will meet the crew, where to park.
- Whether any part of the building has to stay open.
Our emergency commercial plumbing service answers 24 hours a day, and a real person takes those details and sends a plumber.
After the water is off
Start drying quickly. Wet carpet, drywall and ceiling tile hold water. The EPA’s guidance on mold in commercial buildings says to clean and dry wet materials within 48 hours to prevent mold growth. Large losses need a water damage restoration company with extraction and drying equipment. That is a different trade from plumbing.
Have the electrical system checked. If water reached panels, outlets, light fixtures or equipment, an electrician should inspect them before power is restored to that area.
Tell your insurer and your landlord. Report it promptly and keep the photos. In a leased space, the lease decides who repairs what, so notify the landlord in writing.
Notify affected tenants. Tell them which areas have no water and when you expect it back.
Ask what else is at risk. Once the failed section is out, ask the plumber what caused it and whether the same condition exists elsewhere on that line.
What not to do
Do not walk through standing water to reach a panel or a valve. The Centers for Disease Control and Prevention’s guidance on electrical hazards is direct: never turn power on or off, or use an electric tool or appliance, while standing in water.
Do not try to patch a pressurized line and turn the water back on. A failed patch on a two-inch line can release more water than the original break did.
Do not use an ordinary shop vacuum or plug in fans in a flooded area until the electrics have been checked.
Do not turn the water back on to “see if it holds” after a repair you did not make. Pressure testing is part of the repair.
Do not throw the failed pipe away. It is the evidence of what went wrong, and an insurer may ask to see it.
Be ready before it happens
Most of the damage in a burst pipe event is decided before it starts, by whether anyone on site knows where the valves are.
Walk the building once with whoever handles maintenance and find every shutoff in the table above. Tag them. Put a one-page valve map where night staff, security and cleaners can find it.
Operate the main valves once a year so you know they turn. Give after-hours staff the authority to shut the water off without calling anyone first.
A pipe that leaks before it bursts often gives warnings: a stain that comes back, a drop in pressure, a meter that turns when the building is empty. Our guides on the signs of a slab leak in a commercial building and on why a building’s water bill is so high cover those early signs.
Frequently asked questions
What should I do first if a pipe bursts at work? Get people away from water near electrical equipment, shut off the water at the nearest valve you can reach safely, then call the building’s emergency contact and a commercial plumber. Take photos before cleanup.
Where is the main water shutoff in a commercial building? Usually where the water service enters the building, often in a mechanical room or near the backflow assembly. There may also be valves for each floor, riser or tenant space. Find and label them before you need them.
Should I turn off the electricity when a pipe bursts? Only if the panel can be reached from a dry location by someone responsible. Never operate electrical equipment while standing in water. If water has reached a panel or equipment, keep people away and call an electrician.
Can I repair a burst pipe myself until the plumber arrives? Shutting off the water is the correct temporary measure. Improvised repairs on pressurized commercial piping can fail suddenly. Leave the water off for that section until the pipe is replaced and tested.
Who do I call for a burst pipe in an office? Call the property manager or facilities contact and a commercial plumber. For a burst pipe in an office you lease, notify the landlord in writing as well. If a fire sprinkler line is involved, call the fire protection contractor and the alarm monitoring company.
The valve is the whole game
A burst pipe is a bad day that gets worse by the minute until someone closes a valve. The repair itself is routine. Knowing which valve to close, and having someone on site who is allowed to close it, is what separates a wet floor from a closed building.
We repair burst and leaking pipes in commercial buildings across Sacramento, at any hour. Go to the Commercial Plumber Sacramento home page for the full list of what we cover, or call (866) 981-1310 and tell us whether the water is off.