Concrete grades
Grades run from C15 to C60. Strength is the typical result after 28 days. The office confirms the mix for the pour. Prices are not listed.
C15
15N/mm²
Strength at 28 days
Mix. 1 part cement, 2 parts fine aggregate, 4 parts coarse aggregate
Where it is used. Blinding, pathways, and plain mass concrete that is not structural.
C20
20N/mm²
Strength at 28 days
Mix. 1 part cement, 2 parts fine aggregate, 4 parts coarse aggregate
Where it is used. Light domestic work: patio slabs, garden walls, shed bases, hot tub bases, and other non-structural elements.
C25
25N/mm²
Strength at 28 days
Mix. 1 part cement, 1 part fine aggregate, 2 parts coarse aggregate
Where it is used. Flooring, foundations, footings, trench fill, roadworks, and groundwork for domestic and commercial jobs.
C30
30N/mm²
Strength at 28 days
Mix. 1 part cement, 1.5 parts fine aggregate, 3 parts coarse aggregate
Where it is used. Pathways, paving, pavements, driveways, industrial floors, and places with heavy traffic.
C35
35N/mm²
Strength at 28 days
Mix. 1 part cement, 1 part fine aggregate, 2 parts coarse aggregate
Where it is used. Structural piling, external slabs, walls, and commercial work that needs high strength.
C40
40N/mm²
Strength at 28 days
Mix. 1 part cement, 1 part fine aggregate, 1.5 parts coarse aggregate
Where it is used. Commercial construction, foundations, beams, and structures that need exceptional strength, including roadworks.
C45
45N/mm²
Strength at 28 days
Mix. Design mix, proportioned for the pour
Where it is used. Precast elements, long spans, and work in a marine or severe exposure.
C50
50N/mm²
Strength at 28 days
Mix. Design mix, proportioned for the pour
Where it is used. High-rise structure and other work that needs high strength with low permeability.
C55
55N/mm²
Strength at 28 days
Mix. Design mix, proportioned for the pour
Where it is used. Marine and other structures in severe exposure.
C60
60N/mm²
Strength at 28 days
Mix. Design mix, proportioned for the pour
Where it is used. High-rise cores and heavy pavements where the load is extreme.