What Your Home's Pipes Are Made Of, and When Each Kind Fails

Burst Pipes

What Your Home’s Pipes Are Made Of, and When Each Kind Fails

Each time we ask house owners what their house is built from, they answer without hesitation, mentioning brick, fibro, weatherboard. However, when we ask them what materials their pipes are made of, they often stare at us, give no answer or stutter and say something else. Questions like these show us that there is a strange gap, because the materials in your house determine which plumbing system you can use. It also determines the kind of failure you will experience and how expensive your plumbing system will be.

For starters, it is important to note that every pipe in your house has a lifespan and they often present symptoms before dying. In fact, we call these symptoms their signature way of dying. In Sydney, homes were built in waves across the last 150 years, so you will find different pipes material in the mix

Here’s the field guide for you: how to identify the materials in your home, and signs to watch out for before they become problems.

Galvanised steel: the ticking clock

Era: This was the default pipe material used for water from the early 1900s until early 1970s. This type covers the inner-city terraces, interwar bungalows, federation homes and most of the post-war homes.

How it fails: It starts from the inside out. The galvanised pipe is stainless steel coated in zinc. The zinc coating is meant to corrode first, thereby forming a form of protection for the steel material in the pipes. However, the zinc coating eventually dissolves, and over the decades the rust starts. The rusting grows inwardly, builds up and chokes the water pressure, then spreads across the outward before getting through the wall until it is destroyed.

This process happens behind the wall: hence a pipe may look solid on the outside while its wall has become super thin. This damage gets to the pinholes, then splits, making the corrosion system-wide. Unfortunately, when one pinhole happens, more are coming.

The warnings: Watch out:

• Water pressure is significantly dropping.
• Brown or rusty water after no use for a prolonged time.
• Any previous pinhole or repair
• A flow that increases when you turn off a second tap
• Want to do a quick test? A sticking magnet to grey, threaded pipe confirms the material.

The verdict: Galvanised water pipes were made to last for decades, roughly 40-60years. Homes in Sydney haven’t installed them in about fifty years. Do the maths: it is a simple logic. If you have an original galvanized line in your home still working, it is living on borrowed time. This is not a point to panic; instead a call to plan. You must know how much time is left, where the galvanised pipe runs, and have a replacement plan. With galvanised pipes, the question isn’t if it can burst, it is when will it burst?

Copper: the long-serving professional

Era: Around the 1960s, copper pipes took over from galvanised pipes, and it became the standard for supply pipes across Sydney for the next decades. So, if your home was built between the 1960s and 2010, you certainly have a copper system.

How it fails: Copper rarely fails, but when it does, it is a massive failure. Here is why: copper is a genuinely excellent choice for house plumbing. It is rugged, corrosion-resistant and brings at least fifty to seventy years of service. This is to say that most copper piping outlast the homeowners. Plus, it will save you from unnecessary piping drama.

However, copper has a weakness and that is the pinhole. This happens when the water pressure washes off the protective layer of oxide inside the pipe. This typically happens downstream of elbows, in high pressure systems. Pinholes can be caused by either aggressive water flow, or stray electrical currents. The sign to look out for in this failure is a small green crust on exposed pipes or a patch of plaster on concealed pipes.

The meaning of a pinhole: Understanding pinhole is very important. The velocity, chemistry and pressure are all conditions that make up a pinhole. It is important to also note that pinholes come in groups .

One pinhole – simply fix it

Two pinholes – there is a pattern

Three pinholes – It is time to address the pressure and how to limit it, and plan a replacement.

A pinhole is copper’s polite call for attention before certain death, it gives home owners early warning. Galvanised materials do not give home owners such courtesy.

40–60 yrs

The estimated life expectancy for galvanized steel water pipe. Galvanized stainless steel pipes have not been installed in over fifty years. Every installed galvanized line in Sydney is long overdue. No surprise, galvanised replacement is what dominates the burst pipe market.

PEX and modern plastics: the new establishment

Era: These houses were built from the 2000s onward. They have flexible plastics, and cross linked polyethylene. They are mostly the standards in modern houses in Sydney, renovated spaces and bathrooms. PEX are used alongside copper in exposed sections.

Why it took over: Builders use it because it bends conveniently around the corners in the house. Instead of cutting joints of water pipes at every corner in the house, PEX offers flexibility and can be used.

PEX also tolerates freezing better than the copper pipe, especially in a place like Sydney that it freezes. Its installation is also easy; it can be installed without flames in wall cavities and its life expectancy is up to fifty years.

How it fails: PEX rarely fail in the pipes, rather at the fittings. One of the common cause of its failures is a crimped ring, connection that is under pressure from motion, or an early generation fitting. Moreover, PEX has one time enemy which is sunlight. Infact, if the pipes are exposed to a hot water unit, it will slowly brittle and start lagging.

It is also important to note this historical fact: Some plastics like polybutylene failed overseas several decades ago. Hence, the industry in Sydney learns from that, yet the truth remains failures with modern PEX often come from installation.

The supporting cast: Two things that confused home owners

Two things that cause confusion for home owners, PVC and flexi hoses.

• PVC is not a water pipe. It is that white or grey plastic you see in your sewer pipe. This plastic can get blocked or cracked.
• Flexi hoses are also not pipes. They are for fittings. Today, you find them under every, toilet, sink and basin in the house. They have a life span of five to ten years and they are also a major cause of household flooding. Flexi hoses need frequent replacements

Not sure what’s in your walls — or how long it has left?

Get a conditioned assessment for your home. We let you know the material, its condition and the next plan. And it bursts at 9pm, we are just a call away. We’ve got Sydney covered 24/7

Talk to a Burst Pipe Repair Plumber →

Dating your own pipes: the five-minute audit

You don’t need to open your walls to know what material is in there. Look at the exposed spaces: the kitchen sink, where the service enters the house, hot water unit, the subfloor. What you are looking for in these open spaces:

• Galvanised steel is a grey metal with threaded joints. If it is a galvanised steel, a magnet will stick to it.
• Copper is an orange-brown metal, with soldered joints and green crust at its joints. It is best to take a photo of the green crust, that’s a sign that a weeping is starting.
• PEX is usually white, blue or red, and it is a flexible plastic held with metal rings.

The next is to apply the era logic: If your home was built before 1970, and there are no visible evidence of repiping, then it should be assumed that it is galvanised pipes in the walls. Even if you can see copper pipes visible in the walls – many home owners engage in partial upgrades of their pipes especially at accessible points. So, if you judge based on a visible copper pipe, it could be misleading.

Check the renovation history of the house: Not many home owners replace pipes whenever they change the interior of their bathroom and kitchen. This explains why a modern looking tap still brings out brown water or suffers a pinhole after two years of installing a new tap.

What this means street by street

Match the materials of the house, while noting its year of construction and you get the pattern.

The terrace and federation belts: If the house hasn’t been completely renovated, then assume it still has galvanised water steel pipes in its walls.

The mid-century suburbs: Houses in this era used copper, and most of its systems are aging. These houses have pinholes as their signature for failure ehen pressure gets high.

The estate suburbs: These houses were built in the last 20years, and they are all PEX systems. Their pipes are fine, things to watch out for includes: the fittings, if any pipe is exposed to sunlight or the quality of installation.

None of the information provided above replaces the need for expert assessment of your house. These information are to tell you the right questions to ask, and warning signs you shouldn’t ignore during your routines.

Questions we're often asked about pipe materials

1. My house is old but the pipes I can see are copper. Am I safe?
   Maybe. This is one of the most common mistakes we see. Visible pipes often gets replaced quickly, because the problems are easy to detect, but copper pipes aren’t that easy. Copper pipes at the sink, or hot water unit do not show what’s hidden behind the walls or under the floor. If you live in a pre-1970s home, it is safe to assume there is a concealed galvanised unit until a plumber proves otherwise. The real clues to a concealed pipe includes: constant low pressure, and brown water after no use for a long time. Any of these signs shows that there are still old pipes in the home.
2. Is it worth replacing galvanized pipe before it fails?
   Yes, but we often advice home owners to do it strategically. Full preemptive repiping makes sense if you are already renovating the house, and the walls are open, or if you have had massive failure after a few repairs. If you are not in the above category, it is best that you use this approach: firstly assess the pipe system. Then analyze the pipes based on the highest risk to the lowest risk. Replace the highest risk section first: the concealed pipes above the living areas and the buried section, then move to rest.
   What doesn’t make sense and we also don’t advice is paying for repeated patch repairs on pipes that needs to be replaced.
3. Copper versus PEX for a repipe- which should I choose?
   Both choices are excellent, however the quality of the installation significantly affects the installation of these materials. We advice home owners to hire only experts, because the installer matters more than the material.Here are a few comparisons:
   • Copper has proven to be rugged, provides longevity and is great for exposed runs.
   • PEX provides flexibility as it offers fewer joints, hence it can be pulled through walls with minimal damage. This makes its great choice in case of repiping. It is also immune to corrosion and metal pitting.

   Most modern repipes leverage on both materials: PEX for buried sections and copper where exposed. Whatever you choose is still dependent on quality fittings and how experienced the installer is. Infact, a licensed installer determines how your repiping story goes.

4. Do Flexi hoses count as part of my “pipe system” to maintain?
   Yes! Flexi hoses usually have the shortest life expectancy. They often only provide five to ten years of service, and less number of years in coastal salt areas or places with household flooding. So, regardless of whatever materials were used for your walls, the toilets, hoses under the sinks, hoses connected to the washing machine and dishwasher deserves to be cleaned annually and replaced frequently. These hoses before your PEX or copper does.

The bottom line

If you are wondering how aged your house is, take a look at the pipes, except they have been changed in recent times. Moreover, the life expectancy of each material is different from each other. Galvanised steel often age from the inside without notice. On the other hand, copper can stay within the walls for decades but it announces trouble in pinholes that always bring relatives. What many people fail to understand is that modern PEX doesn’t fail on its own. It fails at two things: its fittings and its shade.

Spend five minutes identifying what you’ve got. Do the maths and you will discover what you need: if it is a quick fix, or a warning sign that that shouldn’t be ignored. Your discovery can also be a pointer to the fact that your pipes have outlived their warranty and they need a change.