Does soft water damage copper pipes?

A frequently asked question. Does descaled water damage copper pipes? We would even go so far as to put it the other way round. Limescale-free water is particularly suitable for copper pipes. This has been extensively researched and demonstrated (by TNO. You can find the report by Googling ‘TNO 2012 r10424’).

So where does this myth come from? It’s quite simple. Soft water (low-calcium) water found in nature almost always has a high acidity (pH). And acidic water is corrosive and causes copper pipes to corrode (rust). However, your tap water is not acidic (pH-neutral) and a water softener does not alter the acidity.

So soft water produced by a water softener does not damage your pipes at all. In fact, the coarse limescale in hard water causes pipes to wear out more quickly than softened water, which keeps them clean and smooth.

See also: Is soft water corrosive and therefore bad for the pipes?