Billing
Unexplained water bill spike
Your water usage hasn't changed but your bill jumped 20%+ month-over-month. The most common first sign of a hidden slab or underground leak — water is escaping somewhere you can't see.
Leak Detection · LA & San Diego · Non-Invasive
Find the leak without tearing up your home.
Electronic acoustic listening. Thermal imaging. Pressure isolation testing. Pacific Line's leak detection team pinpoints slab leaks, pinhole leaks, and underground line failures within inches — so when repair is needed, we open one small access point instead of guessing. Serving Los Angeles and San Diego since 2008. Insurance-ready documentation included.
- From $249 flat-rate
- Pinpoint accuracy within inches
- Insurance-ready documentation
- Same-day service available
4,200+Leaks detected
since 2008
since 2008
$249Flat-rate
diagnostic
diagnostic
±3 inPinpoint
accuracy
accuracy
0Floors torn up
unnecessarily
unnecessarily
Warning Signs
Seven signs you have a hidden leak.
Hidden leaks cause thousands in damage before they're discovered. If you're seeing two or more of these signs, book a detection visit this week — before the leak becomes a flood.
Sound
Running water when nothing's on
You hear the sound of running or hissing water when all faucets, toilets, and appliances are off. Most noticeable at night when the house is quiet — often from a slab leak or pinhole in a wall.
Temperature
Warm or damp spots on floors
Concrete floors with warm patches (hot water line leak) or damp spots that won't dry (cold water line leak). Tile grout that stays dark or soft spots in hardwood are red flags.
Structure
New cracks in tile or foundation
Water eroding soil under a slab creates voids that the concrete settles into — causing new cracks in tile, grout, or the foundation itself. Especially common in post-war LA and SD homes.
Air Quality
Mold or mildew smell
Persistent musty or earthy smell near floor level, in closets, or under cabinets — with no visible water source. Hidden leaks create the moisture mold needs to grow behind walls and under floors.
Pressure
Low pressure throughout the house
Sudden drop in water pressure at multiple fixtures — not just one sink or shower. Usually means a leak on the main supply line between the meter and your home, or on a shared branch line.
Water Heater
Water heater runs more than normal
Your water heater cycles on more often even though usage hasn't changed. A hot water line leak forces the heater to constantly replace lost hot water — driving up your gas or electric bill.
Meter
Water meter keeps spinning
Turn off every water source in the house, then check your water meter. If the dial is still moving, water is escaping somewhere — a quick at-home test before you book a detection visit.
Act Now
Seeing 2+ of these signs?
Don't wait. A $249 detection visit now prevents a $10,000+ slab repair or mold remediation bill later. Most California homeowner's policies cover sudden leaks — but not damage from deferred detection.
Book detection — $249 flat-rate
Our Technology
Three tools. No demolition.
Every detection visit uses the same three-tool combination — cross-validated to eliminate false positives and pinpoint the leak within inches.
Electronic acoustic listening
Ground microphones and pipe-mounted sensors amplify the sound of water escaping under pressure. We can hear a pinhole leak through 3 feet of concrete and distinguish it from normal water flow in adjacent pipes.
- ✓ Detects through concrete & tile
- ✓ Hot & cold line differentiation
- ✓ Underground line capable
Thermal imaging
Infrared cameras detect temperature differences as small as 0.1°F — revealing hot water leaks, cold water condensation trails, and moisture behind walls or under slabs that acoustic alone can't see.
- ✓ Sees through walls & ceilings
- ✓ Maps moisture spread area
- ✓ Documents for insurance
Pressure isolation testing
We isolate each branch line with precision pressure gauges and watch for pressure drops. The branch that loses pressure holds the leak — narrowing the search from a whole house to a single line.
- ✓ Isolates leak to one branch
- ✓ Rules out false positives
- ✓ Confirms active vs. old leak
What We Detect
Every leak type — under, in, and around your home.
From slab leaks in post-war bungalows to pinhole leaks in coastal condos, our detection team has handled every category of residential and commercial leak in California.
Most Common in CA
Slab leaks
Copper water lines buried in concrete foundations during post-war construction (1945–1975). Soil movement, corrosive clay, and aging joints cause pinhole leaks under the slab — detectable only with electronic tools.
Especially common in Silver Lake, Sherman Oaks, North Park, and any LA/SD neighborhood with post-war tract homes.
San Diego Speciality
Pinhole leaks (hard water)
Tiny corrosion holes in copper pipe walls caused by aggressive water chemistry. San Diego's 280–340 ppm hard water accelerates pinhole formation — especially in coastal condos and 1980s+ tract homes.
Common in La Jolla, Coronado, Point Loma, and any SD home with copper pipes. See our full hard water guide.
Wall & Ceiling
Wall and ceiling leaks
Leaks in supply lines running through walls or second-floor ceiling cavities. Show up as stained drywall, peeling paint, or dripping from light fixtures. Thermal imaging is the primary detection tool.
Common in multi-story homes, condos, and homes with recent remodeling where supply lines were rerouted through walls.
Detection: $249
Repair (if needed): $380 – $1,200
Includes drywall patching referral
Main Line
Underground supply & sewer leaks
Leaks in the main water supply line between the meter and house, or in the sewer lateral between the house and city main. Show up as soggy lawn patches, sinkholes, or unusually green grass.
Requires underground line locating add-on ($99) plus acoustic detection. Often coordinated with sewer line camera inspection.
Detection: $348 (with line locating)
Repair (if needed): $1,200 – $6,800
Trenchless repair available
Our Process
Detect. Locate. Document.
Every leak detection visit follows the same three-step process — designed to give you certainty, not guesswork. We don't leave until we've either pinpointed the leak or documented that no active leak is present.
Step One
Isolate & test
We isolate each branch line with pressure gauges, check the water meter with all fixtures off, and identify which branch is losing pressure — narrowing the search from the whole house to a specific line.
- Whole-house pressure test
- Branch-by-branch isolation
- Meter check with fixtures off
Step Two
Pinpoint with tools
Acoustic listening pinpoints the leak location within inches. Thermal imaging confirms with visual evidence and maps the moisture spread. Cross-validation between tools eliminates false positives.
- Electronic acoustic listening
- Thermal imaging survey
- ±3 inch pinpoint accuracy
Step Three
Document & recommend
You receive a written report with photos, thermal images, and a repair recommendation. If the leak is claim-worthy, the documentation is formatted for your insurance adjuster. Repair quote if needed.
- Written report with photos
- Insurance-ready format
- Repair quote (if applicable)
Transparent Pricing
Flat-rate pricing. No surprises.
Every detection visit is quoted flat-rate in writing. The $249 diagnostic is credited toward repair cost if you proceed with us. Detection itself is often covered by homeowner's insurance.
Detection fee is credited toward repair cost if you proceed with us. All prices include written report + insurance-ready documentation. View full pricing page →
Why Pacific Line
Why 327 homeowners rated us 4.9 stars.
01
No demolition, ever
We never tear up floors or walls to "find" a leak. Our three-tool approach pinpoints leaks within inches — so when repair is needed, we open one small access point, not your whole house.
02
Insurance-ready reports
Every detection visit includes thermal images, pinpoint location data, technician credentials, and adjuster-formatted documentation. We coordinate directly with your insurance company on request.
03
Detection credited to repair
If we detect a leak and you proceed with repair through us, the $249 detection fee is credited toward the repair cost. No double-charge, no bait-and-switch.
Leak Detection FAQ
Questions we hear every week.
Watch for: unexplained spikes in your water bill, the sound of running water when no fixtures are on, warm or damp spots on concrete floors, cracks in tile or foundation, mold or mildew smell near floor level, low water pressure throughout the house, or a water heater that runs more often than normal.
Slab leaks are especially common in post-war Southern California homes (1945–1975) where copper water lines were buried in concrete foundations. If you're seeing two or more of these signs, book a detection visit this week — before the leak becomes a flood.
We use three non-invasive tools: electronic acoustic listening devices that amplify the sound of water escaping under pressure (we can hear a pinhole leak through 3 feet of concrete), thermal imaging cameras that detect temperature differences from wet spots behind walls or under slabs, and pressure isolation testing that narrows the leak to a specific branch line.
Combined, these tools pinpoint leaks within inches — so when repair is needed, we open one small access point instead of tearing up an entire floor.
Our standard leak detection diagnostic is $249 flat-rate, which includes acoustic listening, thermal imaging survey, and pressure isolation testing — plus a written report with photos for your records or insurance claim. Add-ons like underground line locating ($99) or extended thermal surveys for large homes ($149) are quoted upfront.
If we proceed to repair with us, the $249 diagnostic is credited toward the repair cost — so you don't pay twice.
Most California homeowner's policies cover sudden, accidental water damage from plumbing failures — including slab leaks and pinhole leaks. They typically don't cover gradual leaks from deferred maintenance or pre-existing conditions. Leak detection itself is often covered as part of the claim investigation.
We provide detailed, insurance-formatted documentation including photos, line-item scope, material receipts, and technician license info — and we can coordinate directly with your adjuster.
A slab leak is any water line leak that occurs beneath a concrete foundation slab — usually in copper pipes buried during original construction. A pinhole leak is a specific type of leak where corrosion eats a tiny hole through the pipe wall, often caused by hard water chemistry (especially common in San Diego's 280–340 ppm water).
Pinholes can happen in slab lines, wall lines, or ceiling lines. Both require electronic detection to locate without demolition. See our San Diego hard water guide for pinhole specifics.
Most residential leak detection visits take 90 minutes to 2 hours on-site — including acoustic survey, thermal imaging, pressure testing, and the final written report with photos. Large homes, multi-story properties, or complex slab configurations can take 3–4 hours.
We don't leave until we've either pinpointed the leak or documented that no active leak is present. Rushed detections are how you end up paying for a repair in the wrong spot.
Related Services
Once we find the leak — we can fix it.
Repiping
When multiple pinholes are found — or when your home has polybutylene or deteriorating galvanized pipes — a whole-home PEX-A or copper repipe is the permanent fix.
Learn moreSewer line repair
When the leak is on your sewer lateral — camera inspection, trenchless CIPP lining, or pipe bursting. No digging up your yard or driveway.
Learn moreWater heater service
If the leak is at your water heater — tank, supply line, pressure relief valve, or drain fitting — we diagnose and repair same-day.
Learn more
Expert Guides
Read before you book.
Written by our licensed technicians — the same people who'll show up at your door.
Los Angeles · 14 min read
The Complete Guide to Slab Leak Detection in Los Angeles Homes
Post-war LA bungalows from Silver Lake to Sherman Oaks hide a ticking time bomb under their concrete slab foundations. Our founder breaks down how electronic detection works and what repair actually costs in 2026.
Read the guideSan Diego · 11 min read
San Diego Hard Water: What Every Homeowner Needs to Know
At 280–340 ppm, San Diego has some of California's hardest water. Our SD lead tech explains how that mineral load causes pinhole leaks in copper pipes — and which water softener actually works.
Read the guideDecision Guide · 9 min read
PEX vs. Copper Repiping: The California Homeowner's Decision Guide
After 800+ repipes across LA and SD, here's our honest take: when copper is still the right call, when PEX-A wins on every metric, and the specific situations where we spec each material.
Read the guideHear running water? See the signs?
Book a detection visit — find the leak today.
Call for same-day dispatch, or submit the form for a scheduled visit within 48 hours. $249 flat-rate, insurance-ready documentation, credited toward repair if you proceed with us.