The classic 1:2:4 general-purpose mix. Fine for domestic paths, patios and non-structural slabs on well-prepared ground.
Mix ratio
1 : 2 : 4
Cement : Sand : Aggregate
Proportions & strength
M15 nominal concrete: proportions by volume, typical compressive strength and use.
Designation
M15
Ratio (by volume)
1 : 2 : 4
Cement
1 part
Sand
2 parts
Aggregate
4 parts
Typical compressive strength
2,175 psi · 15 MPa
Typical use
Paths, patios, shed and light slab bases.
Planning reference. Strengths are typical values for a well-made mix at 28 days, not a guaranteed design strength. Structural work must follow your local building code and a qualified engineer's mix design.
Where M15 is used
The classic 1:2:4 general-purpose mix. Fine for domestic paths, patios and non-structural slabs on well-prepared ground.
Nominal mixes like this are proportioned by volume on site and suit general and domestic work. Anything structural - reinforced, load-bearing or engineered - should use a design mix proportioned by weight from tested materials.
Need quantities? The volume calculators give the cubic yards, cubic metres and bag counts for the pour this mix goes into.