Side-by-Side Water Hardness Calculator

Compare Water Hardness

Analyze real-time PPM, Clark degrees, limescale risk, and dishwasher salt settings between any two UK postcode sectors.

Water Quality Comparison Analysis

Executive Summary: Sector BH25 5 vs Sector SW1A 1

Comparing tap water mineral concentration between Sector BH25 5 (South West Water) and Sector SW1A 1 (Thames Water) reveals a water hardness difference of 235 PPM. Sector BH25 5 has softer water at 40 PPM (Soft) compared to Sector SW1A 1 at 275 PPM (Hard).

Limescale risk and boiler heating efficiency vary based on these mineral levels. Households in Sector SW1A 1 experience higher heating element degradation and kettle scale accumulation due to elevated calcium carbonate density (275 PPM vs 40 PPM).

For home appliance setup, Bosch dishwasher water softener settings should be calibrated accordingly: Sector BH25 5 requires setting H00 (No Salt Required) whereas Sector SW1A 1 recommends setting H04.

NP

Sector BH25 5 has 235 PPM LOWER water hardness than Sector SW1A 1

Lower PPM indicates softer water, reduced limescale risk, and lower detergent usage.

Water Metric
Sector BH25 5Outcode: BH25
Sector SW1A 1Outcode: SW1A
Hardness (PPM)
40 PPM
275 PPM
Clark Degrees
2.8 °Clark
19.3 °Clark
Classification
Soft
Hard
Bosch Salt Setting
H00 (No Salt Required)
H04
Water Supplier
South West Water
Thames Water
Postcodes Covered
337 postcodes
66 postcodes