Commercial & multi-unit leak detection in Brisbane, CA

A water-loss problem in an office, warehouse or apartment building raises questions a house never does. An investigation usually begins with the meter and building layout, then narrows the likely source while accounting for tenant access and water shutoffs. Brisbane Leakmark takes commercial and multi-unit inquiries for buildings in Brisbane and the nearby communities shown on our service areas page.

Tell us your property type and what the usage data shows.

Call (415) 532-1415

How is commercial leak detection different from a home visit?

Commercial investigation has additional coordination needs for facility managers, property managers, HOA boards and business owners. The physical problem is the same as anywhere—pressurized water escaping from supply pipes—but the context changes the work.

More meters and piping

Mean more places a loss can hide.

Other people’s spaces

Need notice, access and sometimes permission.

Operations matter

A shutoff that’s a minor nuisance at home can stop a business.

Records matter

Owners, tenants and insurers may each want to know what was found.

What types of leaks affect commercial properties?

Losses in larger properties tend to come from a handful of places. These are examples to check, not a claim about what’s common in Brisbane buildings.

Property type	Places water loss often hides
Office building	Restroom cores, break-room supply lines, rooftop or mechanical equipment
Warehouse or light industrial	Long supply runs, process connections, exterior lines between buildings
Apartment or condo building	Individual unit fixtures, shared risers, laundry rooms, water heater connections
Retail or restaurant	Kitchen and prep-area connections, ice machines, restroom fixtures
Mixed-use	Any of the above, plus boundaries between commercial and residential systems

How can submeters help narrow a building leak?

Before anyone tests a pipe, it helps to know how water is measured on the property:

Utility meter(s): The City’s meter where water enters the property. Some sites have more than one.
Submeters (if present): Private meters that track individual tenants or units.
Common-area supply: Lobbies, landscaping, laundry, mechanical rooms and anything not on a submeter.
Tenant or unit plumbing: Fixtures and lines inside each leased space.

A mismatch alone does not establish a leak. A sketch of what each meter serves is valuable context.

Why might a commercial water bill rise unexpectedly?

A high bill at a commercial property is harder to read than at a house. Several normal patterns can look like a leak.

Pattern	What it might mean	What to compare
Steady rise over several bills	Slow leak, or added occupancy or equipment	Occupancy, new tenants, new equipment
Sudden one-period spike	Burst, stuck valve, or one-time use (cleaning, filling)	Event logs, maintenance records
High use in a closed or vacant period	Leak or always-on equipment	Overnight or weekend meter readings
Seasonal swing	Landscape irrigation or cooling load	Same period last year
Mismatch between utility meter and submeter totals	Different reading periods, unmetered use, meter differences or a possible leak	Align periods and units; map shared uses before assuming a leak

Brisbane bills water every two months, so a problem can run for weeks before it shows up. See why is my Brisbane water bill high?

Active leaks versus unexplained background use

Sorting the situation into one of three categories decides what happens first.

Active and visible

Water on floors, ceilings or pavement. Isolate the affected branch if you can, protect occupants and equipment, then trace the source.

Hidden but measurable

Flow continues during a genuinely quiet period after normal equipment uses are accounted for. Investigate promptly; hidden water can still damage the property.

Ambiguous

Billed use is higher than expected, but scheduled equipment, meter timing and occupancy have not been checked. Start with an accurate baseline.

Information facilities teams should collect

Meter locations and what each one serves
Recent bills or meter readings, ideally a year’s worth
Building drawings or plumbing plans, if available
Locations of main and branch shutoff valves, and whether they work
Occupancy schedule: when the building is busiest and quietest
Recent changes: new tenants, renovations, equipment or irrigation work
Known problem areas, past leaks or prior investigations
The person who can authorize access and shutoffs

Coordinating tenant and common-area access

Agree on the plan with the owner or manager: which areas, which days, who authorizes shutoffs.
Notify tenants or residents in line with the lease or HOA rules.
Consider accessible common areas and shared equipment first when the evidence supports it.
Plan entry into individual spaces with proper authorization and applicable notice when the evidence points there.
Report back so the manager can update tenants.

Protecting occupancy and business operations

Investigations can often be planned around the building’s schedule. Useful questions to settle in advance:

Can testing happen in sections, so most of the building keeps water?
Are there tenants who can’t lose water at all, such as food service or medical uses?
When are the quietest hours, for both access and acoustic conditions?
Who needs to be on site to open locked rooms or approve a shutoff?

System and branch isolation considerations

In a larger building, closing valves one zone at a time is often the fastest way to narrow down where the loss sits. It works only as well as the valves do. Older or seldom-used valves may not close fully, may leak at the stem, or may not be where drawings show them. That’s why isolation findings are treated as evidence to confirm, not a final answer.

Pressure testing in larger buildings

Pressure testing checks whether an isolated section holds. In a big building, it has practical limits:

Only sections that can be fully isolated can be tested.
Long or complex runs take longer to stabilize and read.
Occupied spaces may need water restored before a test can run long enough.
A failed test shows the section is losing water, not the exact point.

Moisture mapping across occupied spaces

When water shows up on finishes, moisture readings help trace its spread. In offices and apartments, readings are taken around furniture, flooring and fixtures that tenants are using. Readings show where materials are wet. They don’t, on their own, prove the water came from a supply pipe rather than a drain, roof or condensation. Learn more in how leak detection methods work.

Mechanical-room and supply-line issues

Mechanical spaces concentrate the equipment where water can escape. Possible sources worth checking include:

Pressure-reducing and backflow assemblies
Booster pumps and their connections
Water heaters, boilers and their supply and relief lines
Cooling equipment make-up water connections
Valve packing and fittings on larger-diameter pipe

Private backflow preventers at businesses must be inspected each year, with results reported to the San Mateo County Cross Connection Control Program—a separate requirement from leak detection.

Commercial irrigation and exterior mains

Larger landscapes and buried lines between buildings can lose water outside, where it soaks away unseen.

Buried supply lines: see underground water line leak detection for how buried lines are investigated
Landscape water budgets: the City points commercial and large landscape accounts to Waterfluence
Turf rules: California AB 1572 phases in restrictions on potable-water irrigation of nonfunctional turf, 2028 for commercial sites and 2029 for HOA common areas

Irrigation investigation is available only if the agreed scope includes it.

What an investigation summary may contain

Areas and systems examined, and dates
Meter readings and isolation results
Methods used and their limitations
The likely leak location or zone, with a confidence level
Areas not accessed and why
Recommended next steps

Detection planning versus repair execution

Stage	Main question	Typical decision-maker
Plan	Which areas and what access?	Facility or property manager
Investigate	Where is the water escaping?	Leak detection provider
Decide	Repair now, schedule, or get bids?	Owner or manager
Repair	How is it fixed and tested?	Licensed repair contractor
Close out	Is use back to normal?	Manager, using meter reads

Our leak detection vs repair guide explains the distinction.

When after-hours work might matter

Some investigations work better when the building is empty: quieter conditions help acoustic listening, and shutoffs disrupt fewer people. Whether evening or weekend work is possible depends on appointment details confirmed by phone. Ask on the call rather than assume it’s available.

Working with building managers and HOAs

Clear communication avoids most delays. Questions worth agreeing on up front:

Who is the single point of contact on site?
Who approves access to each unit or tenant space?
Who can authorize a water shutoff, and for how long?
How will findings be shared, and with whom?
Who arranges the repair once the leak is found?

Brisbane’s Sierra Point and Crocker Park context

Brisbane’s commercial districts sit in different City water districts. Per the City, Sierra Point is part of the Brisbane Water District, and Crocker Park falls under GVMID. Meter, billing and main questions for either go to the City’s Public Works department at 415-508-2130. That tells you which district your building is in, not anything about its plumbing.

Comparing proposals for complex investigations

Criterion	What a clear proposal states
Scope	Which systems, floors and areas are included
Method plan	Which tests, in what order, and why
Access needs	Shutoffs, units entered and how long
Disruption	Expected impact on tenants and operations
Deliverable	Verbal findings, written summary or both
Limits	What the investigation can’t confirm
Repair handoff	Whether separate repair work is available and who is responsible
Licensing	Ask for licensing details, then verify the contractor through the CSLB

Follow-up monitoring or repeat-use patterns

After a repair, meter observations under comparable low-use conditions can help check whether unexplained flow persists, but they cannot prove that every leak is resolved.

Read the meter during a closed period soon after the repair.
Compare the next two bills with the same period last year.
Keep a log of meter reads alongside occupancy changes.
Watch for the same pattern returning, which may mean a second leak or wider pipe wear.

FAQ

Commercial leak detection FAQs

What records should a building manager prepare?

Gather recent bills or meter readings, ideally for a full year, along with a list of meters and what each serves. Add building drawings if you have them, shutoff valve locations, the occupancy schedule and any recent renovations or equipment changes.

Can different tenants create misleading water-use patterns?

Yes. A new tenant, a change in business hours or added equipment can raise use in ways that look like a leak. Comparing submeters, where they exist, against the utility meter and the occupancy schedule helps tell the difference.

How is a commercial water meter tested?

The usual first step is reading the meter when the building should be using no water, such as overnight, and checking whether it still moves. Testing the accuracy of the City’s meter itself is a City matter, so ask Public Works.

Does investigation require shutting off water to the building?

Not always. Many investigations isolate one zone or branch at a time, so most of the building keeps water. Some tests need a short shutoff of a section.

Can an occupied multifamily building be tested in stages?

Often, yes. Common areas and shared risers are usually checked first, and individual units are entered only where the evidence points. Appropriate tenant notice may be required.

What information belongs in an inspection report?

A useful summary lists the areas examined, meter and isolation results, methods used and their limits, the likely location with a confidence level, areas not reached and next steps.

Is commercial repair handled separately from diagnosis?

Usually. Detection locates the problem; repair may involve separate repair work, permits, materials and scheduling around tenants.

Do you schedule work around business operations?

Scheduling and appointment availability should be confirmed by phone and the building’s access arrangements. Call with your quiet periods and any tenants who can’t lose water.

Call to discuss a commercial water-loss concern

If the meter, the bills or a wet ceiling suggest your building is losing water, a short conversation can sort out whether it needs an investigation. Have your meter list and recent readings handy.

Call (415) 532-1415