If you're renovating a bathroom, finishing a basement, or repiping an older home in Kamloops, one of the first questions your plumber will ask is whether you want PEX or copper. Both are excellent materials — but they perform differently, cost differently, and suit different situations. Understanding the trade-offs before work begins helps you make a confident decision rather than just deferring to whatever's cheapest on the day.

What Is PEX?

PEX (cross-linked polyethylene) is a flexible plastic tubing that has largely replaced rigid plastic and, in many applications, copper as the go-to piping choice for residential water supply lines. It comes in three main types — PEX-A, PEX-B, and PEX-C — which differ in how the cross-linking is done during manufacturing. PEX-A is the most flexible and easiest to work with, and it's what most plumbers in the Kamloops area prefer for interior supply work.

How They Compare on the Things That Matter

Freeze Resistance

This matters in Kamloops. Winters in the Thompson region regularly push below -15°C, and homes with poorly insulated crawlspaces, exterior walls, or garage-adjacent plumbing are genuine freeze risks. PEX has a significant advantage here: it expands rather than splits when water inside it freezes, meaning a frozen PEX pipe often survives intact where copper would crack and fail. This doesn't mean PEX is immune to freeze damage, but its tolerance is meaningfully higher. For any exposed or semi-exposed runs — crawlspace supply lines, pipes running through an unheated garage, or lines in exterior walls — PEX is the safer choice.

Corrosion and Water Chemistry

Kamloops's moderately hard water is relatively gentle on copper, but properties on private wells with more acidic water can see early pitting and pinhole leaks in copper supply lines. PEX is immune to corrosion entirely — it doesn't react with water chemistry. If you've had pinhole leaks in older copper and you're on well water, a full repipe to PEX makes a lot of sense.

Cost

PEX tubing itself is significantly cheaper per foot than copper, and installation labour is generally faster because flexible pipe can snake through walls and around obstacles without the fittings and soldering that rigid copper requires. For a full home repipe, PEX can come in 20–30% less expensive all-in. For a small targeted repair or a short run where copper is already in place, the cost difference narrows considerably.

Longevity and Track Record

Copper has been used in residential plumbing for decades and has an extremely well-understood service life — quality copper installations routinely last 50+ years. PEX has been widely used in North America since the 1990s and the evidence so far is very positive, but copper simply has more decades of real-world data behind it. For homeowners who plan to stay in a home long-term and want the longest proven track record, copper still has an edge on that front.

Where PEX Can't Go

PEX cannot be used outdoors in direct sunlight — UV exposure degrades the material over time. It's also not suitable for final connections to appliances like water heaters and boilers where temperatures consistently exceed around 93°C. In these situations, a short copper or CPVC stub-out bridges the gap between the PEX supply line and the appliance.

When to Choose Each

• Choose PEX for whole-home repipes, new construction, basement finishing, runs through crawlspaces or unconditioned spaces, and anywhere freeze risk is a concern
• Choose copper for exposed decorative runs (copper has an aesthetic many homeowners prefer), outdoor sections, connections to water heaters and boilers, or when extending an existing copper system where matching materials simplifies the job
• Mix both — most modern Kamloops homes use PEX for the bulk of supply runs with copper stubs at fixtures and appliances, combining the cost and flexibility advantages of PEX with copper's heat tolerance where it's needed

A Note on Fittings

The quality of PEX installations depends heavily on the fitting system used. Expansion fittings (used with PEX-A) are generally considered the strongest and least failure-prone. Crimp and clamp systems are also widely used and perform well when installed correctly. Brass push-fit fittings are convenient for repairs but shouldn't be used throughout an entire system. Ask your plumber what fitting system they're using and why — it's a fair question and a good plumber will have a clear answer.

Advanced Plumbing Kamloops works with both PEX and copper and will give you a straight recommendation based on your specific project, home, and budget. Contact us to discuss your renovation or repipe before the work begins.