CM13 Brentwood
Harder than the UK average. Expect visible limescale on kettles and taps.
At 388 ppm, Brentwood sits among the UK's hardest water areas — compare it against the softest areas.
What this means for your home
Based on 388 ppm in Brentwood (very hard water).
- Heavy limescale requiring frequent descaling
- Blocked showerheads and reduced water flow
- Substantially higher energy bills from boiler scale
- Dry, itchy skin and lifeless hair
- White crusty deposits on taps and surfaces
- Reduced lifespan of washing machines and dishwashers
Should you soften the water in Brentwood?
A verdict and running-cost estimate based on CM13's 388 ppm reading, for a typical 4-person household.
Water is hard to very hard, so appliance, scale and soap savings typically pay back a softener within a few years.
Appliance impact at 388 ppm: significant: elements fur up, expect earlier failures. Sized for a 4-person home; regenerates roughly every 9 days (estimate). Figures are conservative estimates and vary with household size and usage.
Hardness data for CM13
Sourced from Anglian Water's published water-quality reports and public records.
Hardness measurements
| Parts per million (ppm CaCO₃) | 388 |
| Degrees Clark (°Clark) | 27.2 |
| Degrees French (°fH) | 38.8 |
| Degrees German (°dH) | 21.7 |
| Calcium (mg/L Ca²⁺) | 156 |
Supplier and area
Read the hard water explainer then use the linked postcode checker to confirm if you are in a hard water area; the region averages very hard.
Other areas near Brentwood
Common questions about CM13
What is the water hardness in CM13 Brentwood?
Which water company supplies CM13?
Is the water in CM13 safe to drink?
How can I reduce water hardness in CM13?
What does 388 ppm water hardness mean?
What size water softener do I need in CM13?
How much does it cost to run a water softener in CM13?
Check another postcode
Compare hardness across areas before moving or buying a softener.