Concrete Slab Leak Detection & Repair

Having a leak in pipes buried beneath the concrete foundation of a property can be a big concern. Breaking through a concrete slab and digging in the hope of finding the leaky pipe could mean a large bill for little return.

Our slab leak detection experts use non-invasive methods to find these leaks without needing to dig. This trace and access approach is usually required by insurance to process an escape of water claim.

Call our team today to book a leak detection specialist. We’re available 24/7 and can send a tradesperson within 1-hour for an emergency attendance.

Getting slab leaks fixed promptly could protect your property from structural damage. In extreme cases, external water supply pipe leaks can erode soil to such an extent that it can result in damage to foundations.

In addition, not reacting quickly may result in an insurance claim being rejected. Read more about how to make a successful claim in our knowledge article.

To find a slab leak, our leak detection experts follow a logical procedure. The first part of the investigation is confirming the presence of a leak. For this, they’ll do a series of tests:

1. After turning off the indoor stop valve, a water meter reading will be taken. If there’s a continuous flow of water, there might be a leak.
2. A pressure test will be done on isolated parts of the system. A decrease in pressure is an obvious sign of a leak.

Locating slab leaks

Non-invasive techniques are used along the line the water supply pipe runs:

Acoustic testing:

• Highly sensitive acoustic equipment captures tiny vibrations caused by water escaping pipes.
• Even very small leaks several inches below a concrete floor can be found with this technique.
• A microphone above ground amplifies the vibrations as sounds.

Tracer gas method:

• Pipes are drained and injected with tracer gas, a safe mixture of hydrogen and nitrogen.
• This gas doesn’t cause damage and is completely non-hazardous.
• A specialised device detects the gas as it escapes the pipework, precisely locating the leak.
• The gas can penetrate solid floors such as concrete.

Indoor slab leaks:

• Occasionally, slab leaks occur indoors beneath an internal floor.
• In such cases, thermal imaging might also be used to aid the leak detection process.

Find out more about how we carry out underfloor leak detection.

After our experts pinpoint the likely location of the leak, they’ll dig a small hole to expose it for visual confirmation. The next step will be arranging for repairs.

When we provide an estimate for the repair work, we’ll also include the cost of reinstatement.

Repair work will often involve breaking and removing parts of the concrete slab to mend the broken pipe. After, we’ll reinstate the affected area to the condition it was in before the work began.

NB: We won’t expose a leak that isn’t your responsibility. If the pipe is outside of your property boundary, you should contact your water company for pipe repairs. Read more on which external pipes are your responsibility.

Slab leaks are often inevitable and usually caused by faults in plumbing systems. This can be the result of:

1. Pipe materials: many older homes have cast iron pipes. Unprotected, they can be corroded over time by minerals and water in the soil. Hot water lines made from copper can also decompose over time, allowing for leaks.
2. Movement of soil: some soils expand when wet and shrink when dry. This puts pressure on pipes that can eventually lead to them bursting.
3. Temperature changes: the pipes themselves can also expand and contract in shifting temperatures, resulting in cracks and leaks.
4. Accidental damage: weak spots will result in leaks over time.
5. Electrolysis: sometimes when different metals are in contact (like copper pipes and steel rebar in concrete) it causes electrolysis which increases the likelihood of corrosion.

The signs of a slab leak are not always obvious, but symptoms can include:

• Unexplained water damage including mould and mildew
• High water bills
• A decrease in mains water pressure
• The sound of running water when no appliances are being used
• Cracks in the concrete slab foundation or walls
• Wet patches surrounding the property

You can usually find out if you have a leak by following a simple meter test.