In this guide
- What is a flexi hose and where are they in your home?
- The four types of flexi hose (and their risk profiles)
- The five primary causes of a burst flexi hose
- Seven warning signs your flexi hose is about to fail
- What to do in the first five minutes if yours bursts
- Flexi hose replacement costs (2026)
- The holiday risk: when burst hoses are most devastating
- Flexi hoses and home insurance: what is and is not covered
- WaterMark certification and Australian Standards
- A complete prevention checklist
- FAQs
A flexi hose costs around $20 to buy. When one fails, the average repair bill is $30,000. That gap is why this is one of the most important maintenance items in any Australian home, and why most homeowners have never been told about it.
The problem is that flexi hoses are hidden. They sit inside closed cupboards under sinks, behind toilets, and in laundry cavities. Out of sight and out of mind, they age and corrode until one day they do not hold any more. If you are home when it happens, you catch it within minutes. If you are at work, asleep, or on holiday, it runs for hours.
What Is a Flexi Hose and Where Are They in Your Home?
A flexi hose (also called a flexible braided hose or flexible connector) is the short, bendable pipe that connects your water supply line to taps, toilets, appliances, and hot water systems. They are found everywhere in a modern home because they are cheap, flexible, and fast to install.
A standard flexi hose has three components: a rubber or PEX inner tube that carries the water, a braided outer sleeve (usually stainless steel) that provides structural support, and compression fittings at each end that connect to the supply line and the fixture.
How many flexi hoses does a typical home have?
| Location | Typical number of hoses | Connected to |
|---|---|---|
| Kitchen sink | 2 | Hot and cold tap inlets |
| Bathroom vanity (per basin) | 2 | Hot and cold tap inlets |
| Toilet cistern | 1 | Cold water supply to cistern |
| Laundry tub | 2 | Hot and cold tap inlets |
| Washing machine | 2 | Hot and cold machine inlets |
| Hot water system | 2 | Cold inlet and hot outlet |
| Dishwasher | 1 | Cold water inlet |
A standard three-bedroom home typically has 10 to 14 flexi hoses. Most homeowners have never looked at a single one of them.
The Four Types of Flexi Hose (and Their Risk Profiles)
Not all flexi hoses carry the same risk. The type installed in your home depends largely on when the plumbing was done. Understanding which type you have helps prioritise what to replace first.
The most common hose installed from the 1990s through to the mid-2010s. Black or grey rubber inner tube that expands under pressure. The rubber degrades over time, particularly under heat and humidity. When the outer braid corrodes, the expanded rubber bulges and eventually ruptures. Replace proactively at 8 to 10 years.
PEX (cross-linked polyethylene) inner tube is more dimensionally stable than rubber and expands less under pressure. More resistant to heat and chemical degradation. The outer stainless braiding can still corrode, which remains the primary failure mode. Better than rubber inner, but still needs periodic replacement.
The outer braid is polyamide rather than stainless steel, eliminating the corrosion failure mode entirely. Significantly more resistant to chemical fumes from cleaning products. Increasingly specified in premium installations. WaterMark certified versions are recommended for all new installations.
A single-wall corrugated stainless tube with no inner lining. No rubber to degrade. More rigid than braided hoses. Lower burst risk in most installations but can develop fatigue cracks at bends if kinked or repeatedly flexed. Common in commercial installations.
The Five Primary Causes of a Burst Flexi Hose
Corrosion of the stainless steel braid
The leading cause of burst flexi hoses in Australian homes. Small amounts of moisture enter the braid at the end fittings. Chloride ions in tap water react with the stainless steel strands, causing pitting corrosion. The braiding progressively weakens until it can no longer contain the pressure of the rubber inner tube, which has been slowly expanding. The inner tube then bulges through a weak point and ruptures. This process is accelerated dramatically by chemical fumes from cleaning products stored under the sink.
Age and material breakdown
Flexi hoses are rated for 5 to 10 years. Past this point, the rubber inner tube hardens, cracks, and loses elasticity. The stainless braiding develops micro-fatigue from years of thermal expansion and contraction cycles. Many homes in Australia have original flexi hoses that are 15 to 20 years old. These are statistical failures waiting to happen. The absence of visible external damage provides false reassurance — internal rubber degradation is not visible without removing the hose.
Incorrect installation
DIY or unlicensed installation is a major contributing factor to premature hose failure. The most common installation errors: twisting the hose during fitting (creates permanent stress concentration at the twist), over-tightening the compression nut (deforms the sealing washer, creating a leak point that wets the braid), under-tightening (allows the fitting to weep, wetting the braid), and installing the hose with a tight radius bend (creates a fatigue point at the bend).
High water pressure and hydraulic shock
Flexi hoses are designed to operate at a maximum of 500kPa. Many Australian properties exceed this, particularly on steep blocks where the mains pressure is high, or where pressure-limiting valves have failed or were never installed. Hot water systems also build static pressure during heating cycles. Hydraulic shock (water hammer) creates sudden pressure spikes that stress the hose at its weakest points, particularly near end fittings where corrosion may already be present.
Extreme temperature exposure
Flexi hoses are rated for temperatures between negative 20 and positive 90 degrees Celsius. Hot water service hoses are particularly vulnerable to accelerated degradation when a tempering valve is absent or malfunctioning, allowing scalding water temperatures to reach the hose continuously. Over time, sustained high temperatures cause the rubber inner tube to lose flexibility and crack. Under-sink hoses in kitchens that also house a dishwasher are exposed to additional heat cycles during appliance operation.
Hidden triggers in the home environment Often overlooked
Three commonly overlooked contributors: chemical fumes from bleach, ammonia, and other cleaners stored under sinks attack the stainless steel braid from the outside in, compounding any moisture corrosion. Physical damage during renovations, even minor bumps from repositioning items in a cupboard, can create invisible stress concentrations in the braid. And humidity trapped inside sealed under-sink cabinets creates a perpetually damp microclimate that dramatically accelerates corrosion compared to hoses in ventilated locations.
Seven Warning Signs Your Flexi Hose Is About to Fail
Most burst flexi hoses give visible warning signals weeks or months before failing catastrophically. The problem is that these signals are hidden inside closed cupboards. You have to look for them.
Open every under-sink cabinet, lift the toilet cistern lid, and inspect the laundry cupboard. Do this now, then every six months. Here is what to look for and how urgently to act.
Bulging or swelling in the hose body
The rubber inner tube is pushing through a weakened section of the braid. The hose is under imminent failure risk. Do not run water until it is replaced.
Frayed or broken stainless strands
Individual steel threads of the braid are visibly broken or unravelling. The structural integrity of the hose is compromised and failure can occur at any time.
Active moisture or weeping at fittings
Any visible moisture around the compression fittings at either end of the hose — even a faint dampness on the fitting surface — means water is already escaping under pressure. This will not self-seal.
Rust spots or pitting on the braid
Brown discolouration or visible pitting on the outer braid indicates active corrosion. The braid is weakening. Combined with age, the risk of failure increases significantly.
Discolouration or staining of the plastic coating
Many modern hoses have a clear or white plastic outer coating. Yellow, brown, or black staining on this coating indicates moisture has penetrated the braid beneath it, causing corrosion you cannot see directly. The coating is masking the damage.
Twisted or kinked section
A visible twist or sharp kink in the hose creates a permanent stress concentration. The braid cannot flex uniformly at this point, making it the most likely failure location under pressure.
No expiry tag or unknown installation date
Licensed plumbers typically attach an expiry sticker when installing a flexi hose. If there is no tag, or if the expiry date has passed, the age of the hose is unknown. An uninspected hose of unknown age is a risk by definition.
What to Do in the First Five Minutes if Your Flexi Hose Bursts
Speed matters. A hose discharging at full mains pressure adds roughly 25 litres to the flood every minute. The difference between a $500 clean-up and a $30,000 insurance claim is often how quickly you shut the water off.
Do not panic — act in this order. Every second the water runs, it spreads further under flooring, through walls, and into ceiling cavities below. Your first priority is the water supply, not the contents of the room.
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1Find and close the isolation valve on the burst hose
This is the small tap or lever directly on the hose, between the wall outlet and the hose end. Turn it clockwise (or lever 90 degrees perpendicular to the pipe) to close. If this stops the water, the rest of your home still has supply.
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2If the isolation valve does not close, go straight to the mains stopcock
This also applies if the valve itself is the source of the leak. In most homes the stopcock is in the meter box near the front boundary or at the side of the house. Turn it clockwise to shut off all water to the property. Do this without hesitation.
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3Turn off your hot water system
An electric hot water system left running with no cold water supply will overheat its element. A gas system will fire continuously against a closed system. Both can be damaged. Switch the HWS off at the isolating switch or breaker.
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4Move valuables, electronics, and documents off the floor
Get them out of the flooded area. Water spreads rapidly along the subfloor and can travel several metres from the source.
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5Take photos before cleaning up
Document the burst hose, the flooding extent, and any visible water damage. You will need this for your insurance claim.
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6Call SPS Plumbers on (02) 9072 0760
Call before 10:30am for same-day service. Our vehicles carry replacement flexi hoses as standard stock. We will also check every other hose in the property while on-site.
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7Contact your insurer
Notify them of the damage before any clean-up or repair work begins beyond what is necessary to stop further water ingress. Most policies require prompt notification.
If you are away when it happens: Give a trusted neighbour or property manager a key and show them where your mains stopcock is. A hose that bursts while you are on a two-week holiday runs for days. The difference between $30,000 in damage and $150,000 in damage is often one person knowing where the stopcock is.
Flexi Hose Replacement Costs (2026)
The cost of replacing a flexi hose is modest relative to the damage a burst causes. Here is an honest breakdown of what a licensed plumber charges in Australia in 2026.
| Scope of work | Typical cost (2026) | Notes |
|---|---|---|
| Single flexi hose replacement | $180 – $350 | Includes labour, new hose, and testing. Does not include call-out if charged separately. |
| Two hoses (e.g. under one sink) | $250 – $450 | Per-hose cost reduces when doing multiple in one visit |
| Full home replacement (all hoses) | $800 – $2,000 | Typical 3-bed home with 10 to 14 hoses. Best value — plumber is already on-site. |
| Emergency after-hours replacement | $400 – $900 | After-hours call-out (evenings, weekends) attracts significant surcharge |
| Flexi hose + isolation valve installation | $250 – $450 per point | If no isolation valve exists at the hose — strongly recommended for all toilet and sink connections |
SPS pricing: SPS Plumbers charges a flat rate per job, not by the hour. The price quoted before work starts is the price on the invoice. Members pay no call-out fees. The most cost-effective approach is to replace all flexi hoses in a single visit rather than replacing them one by one as they show signs of wear.
The Holiday Risk: When Burst Hoses Are Most Devastating
Suncorp claims data consistently shows that the cost and severity of burst flexi hose insurance claims peaks during holiday periods. Christmas and Easter school holidays, long weekends, and extended overseas trips all correlate with larger claims, for an obvious reason: when nobody is home, there is nobody to turn off the water.
A hose that bursts at 11pm while the household is asleep runs for six to eight hours before anyone notices water seeping under bedroom doors. A hose that bursts while the family is away for two weeks runs for 336 hours. The volume of water discharged in those two scenarios differs by a factor of roughly 40. So does the damage.
- Before any trip away, shut the mains stopcock. This takes 30 seconds. If something fails while you are gone, the water that escapes is only what was already in the pipes, not what would have been pumped in at full mains pressure for days.
- Consider a smart water leak detector under every sink and at every appliance hose. Wireless sensors that alert your phone cost $25 to $80 each and activate within seconds of water contacting the floor. For homeowners who travel regularly, these are one of the highest-ROI home protection investments available.
- Have your flexi hoses inspected before a long trip rather than after. A licensed plumber can assess every hose and replace anything borderline in a single visit.
Flexi Hoses and Home Insurance: What Is and Is Not Covered
This is the area where Australian homeowners are most commonly surprised. Understanding your policy before a burst happens is the difference between a covered claim and an out-of-pocket catastrophe.
- Sudden water damage caused by the burst hose to floors, walls, ceilings, and contents
- Temporary accommodation costs if the home becomes uninhabitable (check your specific policy)
- Professional drying and remediation of water-affected areas
- Mould remediation if caused directly by the water damage event (not pre-existing mould)
- The cost of the replacement hose itself — treated as maintenance, not insured damage
- Damage attributed to gradual leaking rather than a sudden burst — insurers will look for evidence of prior weeping, moisture staining, or cabinet damage that preceded the event
- Claims where the hose was installed by an unlicensed person — this is explicitly excluded in many policies, and insurers actively check installation records when large claims are submitted
- Claims where the hose was visibly deteriorated and the homeowner can be shown to have been negligent in not replacing it
The unlicensed installation exclusion is real and frequently applied. If a homeowner or unlicensed handyperson replaced a flexi hose and it subsequently burst, the insurer can deny the claim on the basis that the work was not compliant. The financial exposure in this scenario is the full $30,000+ average claim cost, personally. Always use a licensed plumber for flexi hose replacement.
WaterMark Certification and Australian Standards
All flexi hoses installed in Australian plumbing systems must carry WaterMark certification under AS/NZS 3718 (Water supply — tapware) and related standards. WaterMark certification confirms that the product has been independently tested and approved for use in a water supply system in Australia.
- The WaterMark symbol, a capital W inside a water droplet, should appear on the hose or its packaging
- An 8-digit WaterMark licence number must also be present for the certification to be valid
- Non-certified hoses (including many sold cheaply through online marketplaces from overseas sources) do not meet Australian Standards, may fail prematurely, and can void your home insurance
- Always ask your plumber to confirm the hose they are installing is WaterMark certified
The recommended upgrade for new installations is a polyamide-braided hose with a PEX inner carrying WaterMark certification. These eliminate the corrosion failure mode of stainless steel braiding, are more resistant to chemical exposure, and have demonstrated lower failure rates in Australian conditions.
A Complete Prevention Checklist
Follow this checklist to reduce your flexi hose burst risk to near zero.
- Inspect every flexi hose in your home every six months. Open all under-sink cabinets, check behind the toilet cistern, look in the laundry cupboard. Look for rust, fraying, bulging, or moisture. It takes under 10 minutes for the whole house.
- Replace all flexi hoses at or before the 10-year mark regardless of visible condition. Internal rubber degradation is not always externally visible. Proactive replacement is significantly cheaper than reactive emergency repair.
- Have your water pressure tested. If your supply pressure regularly exceeds 500kPa, a pressure-limiting valve is warranted. High pressure accelerates hose wear across every fitting in the home.
- Install isolation valves on all toilet, sink, and appliance connections if they do not already exist. An isolation valve lets you cut water supply to a single fixture in seconds during a failure, without shutting off water to the whole property.
- Never store bleach, ammonia, or caustic cleaning products directly under sinks where flexi hoses are installed. The fumes accelerate stainless steel corrosion. Store them in a ventilated location away from hoses.
- Use only WaterMark-certified hoses installed by a licensed plumber. Cheap hoses from hardware stores or online marketplaces may not meet Australian Standards. The extra cost of a quality hose is trivial compared to insurance excess and repair costs.
- Shut the mains stopcock before going on holiday for more than two to three days. This single habit eliminates the catastrophic holiday-period claim scenario entirely.
- Install a smart water leak detector under each sink and at each appliance connection. They alert your phone within seconds of a failure and cost $25 to $80 each.
- Keep records of flexi hose replacement dates and the licensed plumber who did the work. If you ever need to make an insurance claim, this documentation protects your claim from being denied on grounds of negligent maintenance.
