Is it really worth switching from copper pipes to multilayer tubing?

Multilayer tubing has an advantage that's often not considered enough: it's much easier to install and modify! If you need to add a connection, make a diversion, or repair a section, with multilayer you work in shorter timeframes and with less damage to the walls. With copper, on the other hand, any modification becomes a more complex and expensive operation, especially if the pipes are already embedded.

But here's the real point: if your system is working, replacing everything isn't worth it from any angle. Copper lasts a lifetime! It only makes sense to switch to multilayer if you're already doing renovations and you have to open everything up anyway, or if you have serious corrosion problems that are causing continuous leaks. In that case, yeah, you take advantage of the moment to make the switch and save on the labor costs of tearing out and rebuilding.

Another thing that matters is space: multilayer has slightly smaller external diameters, so if you have tight piping or lots of runs behind furniture, it could come in handy. But honestly, if your copper pipes aren't giving you any trouble, just leave it alone!

One thing nobody mentions: composite tubing ages worse if exposed to UV rays or repeated high temperatures (like in an attic or near heat sources). Copper is practically immortal, composite has an outer layer that degrades over time and can develop invisible cracks before you even notice. If your copper pipes are hidden inside the walls and you don't have leaks right now, leave them alone - the cost and hassle of the work isn't worth it, seriously.

If you want to actually save on initial costs, multilayer piping is worth it especially if you need to do major work right now (new connections, renovations); but if the copper is still working fine, waiting makes sense because labor costs are what weighs on your wallet the most. One practical thing: copper holds up better over time, and multilayer can give you problems if it's installed in bad conditions, so think carefully about where the pipes will go before you decide.

What comes to mind for me is the maintenance thing over time: copper can develop a green patina (verdigris) which technically isn't a problem, but aesthetically it can be annoying if the pipes are visible 😅 Multilayer tubing stays clean, but like someone said it has its limits with prolonged heat. I'd say the switch is only worth it if you're already doing a serious renovation, otherwise it's an expense that really doesn't pay for itself.

The smartest choice is to check whether your pipes actually have problems before spending a fortune. If the copper is still working fine without leaks or visible corrosion, throwing it away is just a waste of money. Multilayer pipe has pros and cons that need to be balanced based on your specific situation, it's not a magic solution.

What struck me reading the other comments is that nobody pointed out: the real advantage of multilayer pipe isn't durability (which is lower than copper anyway), but practicality during installation. If you're already doing major work in your house and need to add new connection points or change the routing, multilayer pipe makes life enormously easier compared to copper. It costs less in labor too because it's faster to lay and doesn't require special skills for the joints.

But watch out: multilayer pipe suffers more than copper in extreme conditions (intense heat, direct light), so if you have pipes in the attic or next to heat sources, copper remains the better choice long term. Basically, switch to multilayer pipe only if you're already doing structural work; otherwise, keep the copper you have.