What is the Best Mix for Concrete UK?

The best concrete mix in the UK depends on your project’s load, exposure conditions, and whether you’re hand-mixing or ordering ready-mix. A concrete mix ratio of 1:2:4 (one part cement, two parts sand, four parts aggregate) suits most domestic jobs. For stronger applications like driveways and foundations, a C25 concrete mix with a 1:1.5:3 ratio delivers better performance.

Understanding UK strength grades helps you choose correctly. C10, C20, C25, and C35 refer to the concrete’s compressive strength in Newtons per square millimetre (N/mm²) after 28 days of curing. Higher numbers mean stronger concrete.

What is a Concrete Mix Ratio?

A concrete mix ratio tells you how much cement, sand, and aggregate to combine. The format is simple: cement: sand: aggregate. For example, 1:2:4 means one part cement, two parts sand, and four parts gravel or crushed stone.

The water-cement ratio also matters. Less water creates stronger concrete but makes mixing harder. More water improves workability but reduces strength. The sweet spot is adding just enough water to make the mix hold together without being soupy.

Concrete Mix Ratios Used in the UK

Different projects require different strength levels. The ratio you choose affects how well your concrete performs under load and weather exposure.

Common “General Purpose” Mixes

Here’s a quick breakdown of popular UK concrete mix ratios:

• 1:3:6: Light-duty nominal mix. Best for blinding, bedding, and non-structural work.
• 1:2:4: Medium-strength nominal mix commonly used for shed bases and patios. Strength varies based on materials and water content.
• 1:2:3: Stronger nominal mix for domestic floors and general groundwork where higher strength is needed.
• 1:1.5:3: High-cement mix suited to driveways and heavier domestic applications, though only ready-mix guarantees a specific grade.

Bagged all-in ballast combines sand and aggregate in one product. Mix it with cement at about 1 part cement to 6 parts ballast for light work, or 1 part cement to 4 parts ballast for stronger results.

For more information on What is the Best Mix for Concrete UK? talk to Pro-mix Concrete Ltd