Hardness and scale · Whole-home
Ion-exchange water softener
A plumbed system that exchanges hardness minerals for sodium, mainly to reduce scale and improve lathering rather than to make public tap water safer.
Back to finderWhat it may fit
- reducing scale
- changing hard-water behaviour in appliances and washing
Key attributes
- primary job
- hardness
- installation
- whole-home
- no professional installation
- false
What to check or avoid
- Using softened water to prepare baby formula
- Removing the separate unsoftened drinking-water supply without advice
Safety note
The Inspectorate advises retaining an unsoftened kitchen supply for drinking and cooking because softening can add sodium and alter taste.
Evidence note
What the signal means here
The Drinking Water Inspectorate describes ion exchange as the common softening process and notes there are no health-based guidelines for water hardness.
Sources and further reading
- Domestic water filters and softeners — Drinking Water Inspectorate Checked 2026-08-31