The debate of PEX vs. Copper has been raging on the internet and among the plumbing fraternity for quite a long time.
Honestly speaking, both these materials have their ups and downs. That said, it’s your personal preference and purpose of usage that decides the perfect material. So, which one should you prefer?
The answer depends on the type of installation you are going to do. You must consider what you are going to use every kind of installation for, either for the conduction of water in your home (plumbing or drinking) or for gas or heating purposes.
Once you know what the purpose of your installation is, then it would be easy for you to perfectly come to a conclusion.
PEX vs. Copper Comparison
For allowing you to choose the perfect material, we have compared PEX and Copper, head to head, under 15 different determining factors. So, without wasting any time, let’s unveil one by one-
Copper Wins in the Temperature Test
If you subject both pipes to a heat source, you will verify that copper has better resistance to a higher temperature than PEX. Copper resists up to a temperature of 600º centigrade as compared to 110 degrees of PEX.
Copper has Edge Over PEX in Pressure Test
PEX resists up to 75 bars of pressure without suffering any deterioration. Copper with a good solder resists up to 300 bars of pressure. Here again, the copper shows strength.
Tensile Test: Copper Wins
If both pipes were subjected to an external stretching force, PEX resists up to 35N / mm2 and copper up to 274N / mm2. Surprisingly, Copper has an edge over PEX on tensile strength as well. I, personally, didn’t expect that!
Dilation Test: Copper Again
By increasing the water temperature to 50ºC, the pipe undergoes a significant expansion more noticeable in PEX than in copper.
As can be observed copper has the upper hand in the properties mentioned above, but the game is not over yet; let’s continue analyzing some other important aspects. Remember, strength is not everything.
Since the introduction of cross-linked polyethylene (PEX) tubing in the residual plumbing market, copper tubing has steadily lost popularity. PEX and copper are plumbing options; however, the 2008 economic crisis forced potential homeowners, plumbers, and building contractors to economize without compromising quality.
In terms of materials, both copper and PEX have their advantages and disadvantages; Consequently, there are several factors to consider before making a final decision.
Material Cost: Copper Loses to PEX
Escalating copper prices, theft, storage, transportation, and labor costs all affect the price of copper tubing. Despite the added cost of required PEX tools, using PEX instead of copper shows a low cost when you make a point-by-point comparison. PEX’s low price does not mean that the manufacturers compromise quality, material durability, or safety.
However, some other factors also have an impact on your purse. The amount you spend on plumbing will depend on the number of fixtures you have in your home, including your sinks, bathtubs, showers, and toilets.
Other factors that determine cost include your home’s size, whether you have repaired or cut holes in the walls and ceilings, and ease of access to the areas where you will install the pipes.
PEX vs. Copper Plumbing Estimated Cost
PEX tubing or cross-linked polyethylene flexible plastic tubing for a house costs about $1,500 to $8,000, according to “CostHelper.” (All cost estimates in this article are based on the same source). For example, it costs about $1,500 to $2,500 with PEX for a bathroom. This estimate is based on standard or averages of distance, length, etc. However, you may get the basic idea.
The price of copper fluctuates, and therefore the price of a house with copper plumbing pipes also fluctuates. Plumbing with copper pipes costs $2,500 to $15,000. For example, using copper tubing in a two-and-a-half bath home with fixtures costs up to $5,000.
Additional Costs with PEX and Copper
You should include or expect to pay $600 to $2,000 for a water treatment system when installing PEX or copper pipes if you have toxic water in your home. Piping a house yourself is not recommended by most experts, but if you do, expect to spend $10 to $60 for 10-foot lengths of 1/2-inch to 1-inch-diameter hard copper tubing.
Special tools like pex clamper and expanders are needed to work with PEX tubing, which costs around $50 to $400 each. Another expense will be permit fees, which cost approximately $70 to $400. Also, you would have to spend $ 50 to $ 150 for the contractor to be present during construction or planning inspections from the local department.
Installation: PEX or Copper – Who Wins?
PEX is flexible and comes in 100 to 300-meter spools. Unlike rigid copper, it does not need to be cut into manageable lengths. It reduces transportation and storage costs. In addition to the possibility of installing long sections with 90-degree curves, it reduces installation time. PEX requires fewer in-line elbows and connectors.
In addition to the above, PEX clamps do not require soldering, corrosive fluxes, or glue. These factors represent a reduction in labor and material costs compared to copper. However, the tools and materials you need to braze copper cost less than the materials and tools to make the PEX connections.
Connections are where you join two tubing pieces and where you create a connection location for fittings and equipment. You make copper connections depending on whether it is hard tubing or soft tubing. Hard tube uses welded connections, while soft tube uses compression fittings.
On the other hand, you make PEX connections with compression fittings or compression pliers. Each type of clamp requires a unique tool. There is no open flame to deal with as with brazed copper fittings.
You can adapt PEX and copper pipes so that the pipes will connect with other types of plumbing material. In most cases, threaded adapters are used that use native connections from both types of tube or pipe.
Fittings are used for soft copper tube compression, and hard copper tube fittings welded connections. The tube and fitting are heated with a torch until the solder flows into the joint. The tube and fitting are joined when the solder hardens.
When using compression fittings, you slide a nut and gland onto the tube, insert the tube’s end into the fitting and then tighten the nut onto the fitting. It compresses the bushing and creates a tight seal.
PEX fittings are made of brass, and they slide into the end of the tube and are clamped. Compression-type PEX fittings use the same principle as compression fittings for copper. PEX compression fittings are made of plastic. However, the difference arises here.
PEX requires a skilled hand for the fittings and additional precautions. In many instances, the PEX fittings start to leak earlier compared to copper, which is more reliable in this context. The leakage means drainage of water or contamination from external sources.
The pipe and fittings must be free of dirt, dust, debris, and copper burrs to achieve a good fit. There are several ways to clean copper water pipes, and all are equally effective.
Distribution of Tubes
Plumbers distribute hard copper tubing by joining lengths and solder fittings at the corners. Depending on your need, you can also do it to branch or split the lines. You continuously distribute the soft copper tubing by bending it at the corners, using compression couplings and tees to extend or split a line.
PEX tubing in a continuous stroke, without any accessories when turning corners or changing direction. You can use couplings in a very long series, and when you need a single line branch from two lines, you need a tee.
Hard copper tubing connections cost less in materials and tools than PEX, but it takes more skill to make them. Soft copper tubing connections are similar to PEX in cost and require roughly the same skill.
The copper tube is a weldable material, is easily repairable, and at the same time, easier to install in places where we have many bends and crosses.
Lifespan: Copper or PEX?
Most manufacturers cover PEX pipes and fittings with a 25-year limited warranty. Unlike copper, PEX will not corrode when exposed to low pH water or buried in acidic soils.
Additionally, scale build-up and long-term clogging are eliminated with the use of both PEX and copper; therefore, the water flow and pressure will remain constant over the years.
However, PEX deteriorates in direct sunlight; you cannot use it outdoors. UV rays are PEX arch enemy. On the other hand, copper can be used outdoors and can be designed to have a beautiful look.
As mentioned above, copper resists temperature up to 600 degrees Celsius. PEX loses its sheen, and after six months of exposure to sun rays, it deteriorates.
However, copper plumbing is prone to rupture during freezing conditions; PEX resists freezing due to its flexibility and compensates for expansion caused by ice water. It avoids the added cost and hassles of blast pipes.
You can see one is good for winters and one is good for summers. Depending upon your usage and temperature zone, you have to choose which is the better option.
While PEX has a smaller inside diameter than the same size copper pipe, tests on a residential piping system showed that it still offers the same flow rate as copper.
Copper does not burn, does not excite combustion, and does not emit volatile gases in a fire. PEX must be protected from excessive ambient heat.
Reliability: Copper or PEX
PEX plumbing requires 50 percent right angle fittings as compared to Copper. The reduced number of right angles in PEX reduces the number of potential leaks.
On the other hand, copper is also reliable. According to the Copper Development Association, since 1963, seamless copper piping has been installed in approximately 80% of all buildings in the United States.
The biggest challenge to its reliability is the potential for pinhole leakage. Corrosion of copper tubing is rare but can be costly.
Both copper and PEX pipes are widely accepted in building codes. Copper has a long history of use in homes. There are cases in which copper develops leaks due to the materials in the water, and in other cases, it is in contact with acid soils that have high concentrations of carbonates.
PEX faults are related to earlier stages of clamps failing, installations not following manufacturer’s specifications, and faulty accessories.
Comfort in Use & Installation
Since copper has thermal conductivity, hot water on its way to the shower or kitchen sink must heat the pipes. PEX, on the other hand, does not drain heat energy easily. It means that when a kitchen or shower faucet is turned on, hot water is delivered much faster than in a copper-based installation.
Also, because PEX tubing is flexible, it helps absorb sudden surges in water pressure, which can cause metallic water hammer noise in copper tubing.
However, MTBE or T-Butanol chemicals in the making of PEX piping cause the water to react with the material. It is harmful, so you have to make sure to flush the water two or three times before usage.
Health Considerations and Safety
Copper is known to resist the growth of bacteria for long periods. However, since PEX has been used in plumbing installations for a relatively short time, its resistance to bacterial growth is unknown.
On the positive side, PEX has been approved for use with drinking water, hospital plumbing, and medical equipment manufacturing, such as heart-lung kidney and dialysis machines.
PEX is likely to emit plastic particles over time. However, this also applies to FDA-approved food and beverage containers. Copper is eco-friendly as it can be recycled, while PEX canopy is recycled and contains chemicals harmful to the environment.
Copper, on the other hand, can contribute to health. Food and Nutrition Board recommends a daily intake of 1 to 3 mg of copper. When copper comes into contact with water, it creates a copper oxide film that prevents the proliferation of bacteria or fungi in the water and comes into contact with our body.
Plumbers use copper tubing because it allows water to flow freely without mineral build-up of scale, providing a tasteless and odorless water supply. Cleaning copper water pipes is an important step when adding or upgrading existing plumbing.
What you have read above is factual and true; it largely depends on your requirement and your plumber to carry out the installation.
If the installation does not take much of the pipe, it will depend on the plumber’s ability to work with one material or the other.