PEX Pipe vs Copper Pipe

For both DIYers and plumbing professionals, choosing the right piping material is crucial for long-lasting, high-performance results. The two most common options for supply plumbing are crosslinked polyethylene (PEX) plastic tubing and traditional copper pipes. Both provide excellent capabilities, but each has pros and cons across factors like durability, cost, installation, and sustainability.

 

As a veteran plumber, I’ve worked extensively with both PEX and copper. In this comprehensive guide, I’ll compare PEX vs copper piping to help illuminate which solution may be ideal for your residential or commercial application based on priorities like budget, ease of installation, lifespan, corrosion resistance, and long-term value. We’ll examine differences in cost, performance, maintenance, cold weather usage, aesthetic appeal, and more between PEX and copper. My goal is to provide an unbiased expert perspective to help select the best plumbing material for your needs.

 

PEX Pipe Overview

First, a quick introduction to PEX tubing. PEX stands for cross-linked polyethylene, a specialized plastic piping material used for both supply plumbing and radiant heating systems. Its key characteristics include:

- Highly durable yet flexible tubing. Withstands freezing and resists corrosion and scale buildup.

- Simple push-fit, crimp, compression, or expander connections. No soldering or gluing is needed.

- Easy for DIYers to install. Can bend around corners, reducing connections versus copper.

- Three common grades available: PEX-A, PEX-B, and PEX-C, which vary in temperature/pressure ratings.

- Available in sizes from 1⁄4” to 2” for residential applications. 1⁄2” to 1” is the most common.

- Lifespan of 50+ years if properly installed. Maintenance-free.

- Inexpensive compared to copper, plus lower labor costs.

With its flexible tubing, simple connections, and corrosion resistance, PEX has gained immense popularity as an alternative to traditional metal piping. But how does it truly compare?

 

Copper Pipe Overview

Copper plumbing has been used for decades in residential and commercial buildings. Its defining characteristics:

- Rigid metal pipes instead of flexible tubing like PEX. Makes routing directly more challenging.

- Requires soldering copper fittings together for gas-tight seals. Installation skill intensive.

- Type K and Type L are the most common: Type K heavier walled, and Type L thinner walled.

- Excellent corrosion resistance. A smooth interior minimizes scale buildup.

- Available from 1⁄4” to 12” diameter. 1⁄2” to 3⁄4” standard for residential supply plumbing.

- The long lifespan of 30-70 years based on water chemistry. Prone to pinhole leaks over time.

- Expensive material, though the cost is partly balanced by recyclability. High labor costs.

 

With its proven performance but demanding installation, copper remains popular but requires weighing pros and cons versus simpler PEX.

 

Comparing Costs: PEX vs Copper

One major consideration for any plumbing material is cost, both in materials and labor:

 

PEX:
- Inexpensive polyethylene tubing, typically $0.50-$2.00 per foot.
- Low-cost fittings like crimp rings. Complete connections cost as low as $2.
- No specialty tools are required. Crimpers, expanders, and tubing cutters are inexpensive.
- Fast installation time due to simplicity.
- DIY friendly reduces labor costs.

 

Copper:
- Copper pipes alone are $2-$10 per foot, based on diameter and copper commodity markets.
- Solder and flux required to join copper fittings and valves.
- Professional soldering tools like torches are required.
- Intensive installation time to cut, deburr, flux, solder, and inspect joints.
- Requires skilled trades for installation, increasing labor costs.

Overall, PEX material and installation costs can be 50% or less than comparable copper plumbing. While the material cost differential narrows for larger-diameter commercial piping where copper prices per foot are lower, PEX retains installation speed and labor cost advantages. This makes it highly economical for large-scale plumbing applications.

However, copper provides value through:
- Scrap salvage/recycling offsets some material cost
- Fittings like valves are reusable if not overheated during soldering
- Does not require replacement as often due to longevity, lowering lifetime costs

For accessible above-grade supply plumbing conveying potable water, carefully weighing price against application factors guides material selection. Cost advantages vary based on scale, building lifespan, and other variables.

 

Performance Factors: PEX vs Copper

Beyond raw costs, performance factors also impact material comparisons:

 

PEX:
- Flexible tubing simplifies routing through joists and framing. Easier “rough in”.
- Zero risk of leaks from accidental torches or solder splatter.
- Up to 50% fewer fittings than copper due to flexibility.
- Easy to retrofit or modify existing plumbing.
- Quieter water flow compared to rigid copper pipes.
- Maximum 200°F temperature rating. Suitable for hot water lines.
- Can withstand up to 200psi pressure for 1/2” tubing.

 

Copper:
- Rigid pipes with elbow fittings require planning and skill for routing.
- Danger of accidental fire damage if soldering is mishandled.
- Flows exceptionally well when smooth and properly soldered. Low friction losses.
- Withstands up to 250°F if properly insulated. Ideal for solar thermal piping.
- Can last 50-70 years in ideal conditions. Outlasts most building elements.
- Strong pipes help reduce water hammer noise and damage.

For performance, weighing priorities around routing complexity, future flexibility, operating conditions, and application against the strengths of each material guides selections. PEX simplifies many installations, while copper maximizes longevity in the right conditions.

 

Installation Factors: PEX vs Copper

 

Ease and speed of installation also impact comparisons:

PEX:
- No special skills are required. Basic tools for cutting and connections. Good for DIY.
- Fast installation. Simply cut pipes, push-fit connections, and secure.
- Flexibility allows routing through framing gaps. No skill is needed for neat running.
- Push-fittings like Sharkbite allow quick connections without clamps/crimping.
- Fewer connections than copper due to flexibility.
- Expander tools make solid airtight joints.

Copper:
- Soldering skills essential. Years of practice are required for neat joints. Steep learning curve.
- Slow, methodical joint preparation is required before soldering.
- Rigid pipes require planning and skill for neat routing and bending.
- Soldering risks accidentally burning surroundings or self. Fire safety is critical.
- Sanding/cleaning to remove flux residue after soldering.
- Leak-testing and inspection of every joint is time-consuming.

For DIYers or anyone valuing simpler installation, PEX provides a much shallower learning curve. The flexible tubing and push-fittings enable fast connections without involving joint preparation or open flames. This allows for completing projects faster.

However, skilled copper soldering allows extremely neat professional results. Like welding, perfectly mitered and soldered copper joints are an art. And repairs or modifications are straightforward for experts by resoldering accessible joints. Tradeoffs exist between simplicity and craftsmanship.

 

Maintenance Comparison: PEX vs Copper

Once installed, maintenance requirements vary:

PEX:
- No maintenance required. Does not corrode or accumulate scale deposits over time.
- Costly leaks requiring repairs are very unlikely. Lasts 50+ years without issues.
- Flexible tubing more freeze resistant than copper. Less prone to winter breaks.

Copper:
- Periodic pinhole leak repairs are needed in older systems. Joints slowly corrode.
- Re-soldering accessible joints simple for copper repair work.
- Rigid pipes burst if water freezes. More winter draining/insulation is needed.
- Controlled acid flushing helps clear accumulated scale internally over decades.

If correctly selected and installed, PEX should serve reliably for its entire lifespan with no required maintenance beyond the replacement of worn fixtures. Only leaks stem from improper installation. This keeps ownership costs minimal.

With copper, periodic preventative maintenance helps maximize its longevity. And repairs for small pinhole leaks in older piping are eventually needed in all but the most ideal water chemistry. Accessibility makes repairs simple with copper, but costs add up.

 

Cold Climate Usage

For cold regions, material flexibility and freeze resistance matter:

PEX:
- Highly flexible tubing expands when water freezes instead of bursting like rigid copper.
- Less prone to major freeze breaks in less insulated areas like crawlspaces.
- Easier to fully drain down for seasonal home winterization. Flexible PEX has less interior holdup volume.

Copper:
- Rigid copper pipes burst at weak points if the water inside freezes, causing massive leaks.
- Prone to freeze damage in unheated spaces without diligent insulation or heat tracing.
- Can be difficult to fully blow out standing water for winterization in all pipes. Water remains in the elbows.
- Draining systems before freeze seasons is mandatory. Burst copper pipe repairs are expensive.

In harsher northern climates, PEX provides more freeze forgiveness thanks to its flexible composition. Failures requiring major repairs are far less likely. This provides peace of mind for seasonal homes or buildings with varying occupancy and insulation levels.

 

Visual Appeal Differences

Aesthetics may matter for exposed installation locations:

PEX:
- Available in red, blue, white, and other colors by request for color coding.
- Tubing limits customization due to standard sizing. But flexible.
- Push-fittings don’t offer decorative options like polished chrome.

Copper:
- Prized for the beautiful patina finish when natural copper color was allowed to age.
- Standard plastic-coated copper offers a crisp uniform look.
- Wide range of decorative copper fittings and valve handles available.
- Can be cleanly bent by skilled trades into custom curved routing.

For exposed lines where visual appeal matters, copper provides more aesthetic options through finish selection and decorative components. This allows for matching other metallic architectural features for a cohesive look. PEX offers a simpler standard appearance.

 

Recyclability Comparison

 

Both materials are highly recyclable at the end of life:

PEX:
- Tubing itself is 100% recyclable. Recycled into drainage composite piping.
- Fitting metals like copper and brass are fully recyclable.
- Recycling programs improving with demand. Check for PEX recycling locally.

Copper:
- Extremely high scrap value makes copper piping recycling profitable.
- Tubing and fittings are easily recycled into new copper products. Over 80% of US copper pipes are recycled.
- Provides resource efficiency through almost perpetual recyclability.

Recyclability gives both materials strong sustainability advantages. PEX recycling networks are growing to reclaim components at the end of life, adding to their green merits. But copper’s inherent value and extensive recycling infrastructure keep the environmental impact minimal despite higher initial resource demands.

 

Ideal Applications: PEX vs Copper

Based on the factors above, ideal applications align as:

PEX:
- Hot and cold potable water plumbing lines
- Radiant floor heating systems
- DIY home plumbing
- Renovating old metal plumbing inaccessible for repairs
- Trench burial with fewer connections
- Challenging routing situations through framing
- Corrosive water conditions impacting copper

Copper:
- Exposed architectural supply plumbing with decorative fittings
- Solar thermal heating systems with very high temperatures
- Sensitive medical gas piping where zero leeching critical
- Commercial plumbing systems where copper already standardized
- Straight routing patterns requiring little flexibility
- Skilled tradesmen installation for artisan quality joints
- Environments where copper naturally passivates

By matching strengths to needs, both materials can excel in the right contexts. Weigh factors like temperature, pressure, water chemistry, installation skill, and aesthetics for an ideal fit.

 

Common Myths About PEX and Copper

Despite strengths, some false perceptions about PEX and copper persist:

PEX Myths:
- PEX gets "plasticized" and brittle over time - False - PEX is a thermoset plastic that does not degrade with heat exposure.

- PEX tubing bursts easily - False - PEX is highly durable for its lifespan with good installation. Failures result from faulty connections or gross over-pressurization, not the tubing.

- PEX requires expensive proprietary tools - False - Basic PEX installation requires only simple, inexpensive crimpers and cutters available anywhere.

- PEX kinks easily - False - PEX is highly flexible but resistant to kinking under normal handling during installation.

Copper Myths:

- Copper leeches into drinking water - False - Copper alone does not leech harmful contaminants when used for potable plumbing. High water acidity and standing water do slowly corrode copper.

- Plastic pipes like PEX are safer than copper - False - Approved copper has no known leeching or health issues. But wrong flux types can be problematic.

- Copper pipes fail after 20-30 years - False - Properly installed and maintained copper can last 50-70 years or more. Pipe failures result from improper installation or aggressive water conditions.

By busting myths, we enable selections based on actual merits. Both materials play important roles.

 

 

In closing, while newer flexible PEX has gained popularity for its installation simplicity, traditional copper remains excellently suited for long-lasting plumbing systems in the appropriate applications. There is no universally “best” choice between PEX and copper. Carefully weighing project needs against the strengths of each material based on factors like cost, performance, lifespan, aesthetics, and installation requirements guides selection for the ideal fit. In the right setting, both PEX and copper can provide decades of reliable service by matching robust capabilities to application demands. I hope this detailed plumber’s perspective on weighing PEX versus copper assists you in making the most informed choice when planning your next residential or commercial plumbing project. Please don’t hesitate to reach out with any additional questions!