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Leak Detection — Non-Invasive Thermal & Acoustic Methods
Delex Plumbing uses professional thermal imaging cameras and acoustic detection equipment to locate hidden water leaks inside walls, floors, and foundations without unnecessary demolition. Licensed plumbers, same-day service, and accurate diagnosis before any repair begins.
Non-Invasive Leak Detection — Find It Before You Fix It
A water stain on a ceiling or a wet patch on a wall tells you water is present. It does not tell you where the water is coming from. Cutting holes in drywall to chase a leak is expensive, disruptive, and often results in opening the wrong section of wall — missing the actual source while creating significant damage to the finish.
Non-invasive leak detection uses thermal imaging and acoustic equipment to locate the leak source before any wall is opened. Thermal imaging identifies temperature anomalies caused by wet insulation or active water movement behind surfaces. Acoustic detection amplifies the sound of water escaping under pressure inside a pipe. Together, these methods locate most hidden leaks to within a foot of their actual source.
Thermal Imaging Leak Detection
A FLIR thermal imaging camera detects surface temperature differences invisible to the naked eye. Active water leaks cool the surrounding material as the water evaporates; pipe runs behind walls show as temperature gradients against the ambient wall surface. A trained operator can trace the wet area back to its source, identify whether the moisture is active or historic, and distinguish between plumbing leaks and condensation.
Thermal imaging is most effective for supply pipe leaks behind walls or under floors, slab leaks in radiant heating systems, and ceiling leaks from the floor above. For intermittent drain line leaks, a sewer camera inspection is the more appropriate diagnostic tool.
Acoustic Leak Detection
Acoustic leak detection amplifies the sound of water escaping a pressurized pipe to a level that allows pinpoint location through floors and walls. A ground microphone placed on the floor above a buried supply line, or a contact sensor placed against a wall surface, picks up the characteristic frequency of water under pressure escaping through a small opening. This method is particularly effective for underground supply line leaks and slab leaks.
We use both methods together on complex leak locations, where thermal imaging identifies the general wet zone and acoustic detection pinpoints the source to minimize the size of any access opening required.
Slab Leak Detection
Slab leaks — supply pipe leaks inside or beneath a concrete slab — are among the most difficult plumbing problems to locate and repair. The sound of water running under the slab can often be detected when all fixtures are off; a significant increase in the water meter reading confirms active leakage. Thermal imaging of the slab surface, combined with acoustic detection, allows us to identify the leak zone before beginning any concrete work.
For confirmed slab leaks, repair options include spot excavation through the slab, rerouting the supply line through the walls or ceiling (avoiding the slab entirely), or epoxy pipe lining for appropriate pipe types. We present all options with cost and disruption comparisons before beginning work.
Water Leak Repair After Detection
Leak detection and repair are completed by the same licensed plumber in a single visit in most cases. After identifying the leak source, we open only the minimum access required — a small access panel rather than an entire wall section — make the repair, and confirm zero pressure loss before closing up. This approach significantly reduces repair cost and restoration work compared to conventional open-and-find methods.
Leak Detection Service Area
We provide leak detection services across all Mississauga neighbourhoods. For a full system check, book a plumbing inspection alongside the leak detection visit. Call 416-910-2550 for same-day leak detection.
Foundation & Basement Leak Detection
Foundation leaks — water entering through cracks in poured concrete or through porous block foundation walls — are often confused with plumbing leaks because the water appears in the same basement locations. The critical distinction is whether the water is present only after rain events (foundation leak) or whether it appears regardless of weather and corresponds to household water use patterns (plumbing leak). We differentiate these during the initial assessment before recommending any repair.
For suspected foundation leaks, we perform a simple isolation test: turn off all plumbing fixtures and monitor the water meter for movement over a 30-minute period. No meter movement confirms the source is external rather than a supply pipe. This test takes less than an hour and definitively separates foundation water entry from plumbing leaks, directing the homeowner to the appropriate repair contractor.
Active plumbing leaks behind finished basement walls are particularly damaging because they are contained within the wall assembly and have no visible path to drain. Water absorbed by insulation, framing, and drywall can persist for months before becoming visible as a stain or causing structural damage. Thermal imaging is the fastest and least invasive way to locate these hidden leaks — the moisture differential between wet and dry framing shows clearly as a temperature anomaly.
Water Meter Reading — Identifying Hidden Leaks
Your water meter is the first diagnostic tool for identifying a hidden leak. Turn off all fixtures and check the low-flow indicator — typically a small red or blue dial or triangle on the meter face. If this indicator is rotating with all fixtures off, water is flowing somewhere in the system. The rate of rotation gives a rough indication of the leak size: slow movement suggests a small leak such as a dripping faucet or toilet flapper; rapid rotation suggests a significant supply pipe leak.
A sustained increase in your Peel Region water bill without a corresponding change in residential plumbing usage without a corresponding change in household water use is the most common way homeowners discover hidden leaks. Bills are issued every two months in Mississauga — an active leak can go undetected for 60 days before the billing pattern reveals it. We recommend checking the low-flow indicator monthly as a simple early warning practice.
Toilet leaks are the most common source of hidden water loss in Mississauga homes and the easiest to confirm. Place a few drops of food colouring into the toilet tank. If colour appears in the bowl within 10 minutes without flushing, the flapper is leaking — a repair that costs $30 in parts and 15 minutes of labour. An undetected flapper leak wastes approximately 200 litres of water per day or roughly 12,000 litres per billing period.
Same-Day Service — Mississauga's Most Responsive Plumbing Team
Same-day plumbing service in Mississauga is available when you call before 10 a.m. on weekdays. We confirm a two-hour arrival window during your call and send a text notification when the plumber is 30 minutes away. If any scheduling change affects your window, our dispatcher calls you proactively — we do not leave clients waiting without information.
Our service vehicles are stocked with the 50 most commonly needed repair parts and materials. For the majority of Mississauga residential plumbing calls, this means the repair is completed on the first visit without a parts run to the supplier. On the rare occasion where a specialized part is required, we have established same-day supplier relationships and can typically complete the repair the same day in most cases.
Evening and weekend appointments are available for non-emergency work by advance booking. We schedule these appointments at the same flat-rate pricing as weekday service — no premium for Saturday or early evening availability. For clients who cannot take time off work for a plumbing appointment, we provide the weekday scheduling flexibility that makes routine service accessible without using vacation time.
Our service area covers every Mississauga postal code, from L4T in Malton to L5J in Clarkson, and from L5A in Cooksville to L5B in the Square One district. We do not charge additional fees for properties at the outer boundaries of our service area — Mississauga is our home territory and all points within it receive the same response standard.
Why Mississauga Homeowners Choose Delex Plumbing
Delex Plumbing has built its reputation across Mississauga through 10 years of consistent service — same-day response, flat-rate pricing with no surprise charges, and licensed master plumbers on every job. Our 384 verified five-star Google reviews reflect the cumulative experience of homeowners from Port Credit to Meadowvale who called us once for a routine repair and have called back for every plumbing need since.
The three things our clients most consistently cite in their reviews: we arrived when we said we would, the invoice matched the quote, and the plumber left the work area clean. These are not exceptional standards — they are baseline professional standards that should characterize every service business. We treat them as the floor rather than the ceiling of what our service delivers.
Our flat-rate pricing policy means the quote we provide before touching anything is the amount on your invoice when we leave. No overtime charges for after-hours calls. No travel fees for distances within our service area. No material markups disclosed after the job is done. Transparent pricing is how we have maintained a 5.0-star rating across 384 reviews — clients who receive exactly what they were quoted do not leave one-star reviews.
We back every job with a written labour warranty. If something we installed or repaired fails within the warranty period, we return and fix it at no charge. No runaround, no dispute about scope. The warranty documentation is included with the invoice and specifies the exact duration and scope of coverage. For fixture and material warranties from manufacturers, we register the installation and provide the registration confirmation so warranty claims go smoothly without paperwork obstacles.
Licensed & Insured — Leak Detection by Certified Professionals
Every plumber on the Delex team holds a valid Certificate of Qualification from the Ontario College of Trades. This licence is not a formality — it is the legal prerequisite for performing plumbing work in Ontario, and it represents a minimum of 9,000 hours of apprenticeship training plus a journeyman examination that tests both technical knowledge and code compliance.
Full liability insurance protects your property if any accidental damage occurs during our work. Bonded coverage protects you from any dishonesty by our employees while on your property. WSIB coverage protects you from any liability if a worker is injured on your property. These are not optional additions to our service — they are standard protections that every legitimate plumbing company carries and that unlicensed operators routinely lack.
We pull permits for all work that requires them. Ontario Building Code requires permits for new plumbing installations, changes to drain and vent systems, and water heater replacements. A job done without a required permit leaves you without a legally completed installation — a disclosure obligation in real estate transactions and a potential coverage issue in insurance claims. Our permit fees are included in the project quote rather than added as a surprise at the end.
Frequently Asked Questions About Emergency Plumbing
Q: How much does leak detection cost in Mississauga?
A: Leak detection using thermal imaging and acoustic equipment typically costs $250 to $450 as a standalone diagnostic service. When followed by a repair on the same visit, the detection fee is often credited against the repair invoice. Call 416-910-2550 for a free estimate.
Q: I hear water running but all taps are off — is this a leak?
Q: Can you detect a leak without opening my walls?
A: In most cases, yes. Thermal imaging and acoustic detection locate leaks to within a foot of their source in most standard wall and floor configurations. Only a small access opening is needed for the repair — not the entire wall section. This minimizes drywall repair and paint matching.
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Every leak detection job starts with a free estimate. Call 416-910-2550, contact us online, or request service for same-day detection.
