Concrete Mixes & Strengths – A Full Guide

Concrete is used across a wide variety of projects, from domestic DIY jobs to construction work. Each application requires a specific mix and strength to ensure you get the right results. 

Understanding concrete mixes can seem tricky, but this month at Madmix, we’ll explain the common concrete strengths and mixes, along with their use and some technical details to help you when placing your order. And, if you’re still unsure, just reach out to our team who will be happy to help you decide on the right mix for your purposes.

Concrete strengths and their uses

C10 Concrete

• What is C10 ideal for? C10 concrete is ideal for creating non-load-bearing walls, foundations for steps or for filling trenches and cavities. This makes it perfect for drainage works and for simple garden applications.
• Suitability: Suitable for domestic and commercial projects
• Technical strength: 10N/mm2 – 10 Newtons per square millimetre after 28 days of curing

C15 Concrete

• What is C15 ideal for? C15 concrete is ideal for flooring without embedded metal, foundations for small walls and sheds, and for any paving when laying steps and paths.
• Suitability: Suitable for domestic and commercial projects
• Technical strength: 15N/mm2 – 15 Newtons per square millimetre after 28 days of curing

C20 Concrete

• What is C20 ideal for? C20 concrete is ideal for foundations on a wide range of projects, from walls to house extensions and conservatories. It is one of the most commonly used mix types and works well as a base for sheds and garages.
• Suitability: Suitable for domestic and commercial projects
• Technical strength: 20N/mm2 – 20 Newtons per square millimetre after 28 days of curing

C25 Concrete

• What is C25 ideal for? C25 concrete is ideal for the aforementioned foundations and flooring, but can also be used for trench filling. This means it is applied widely in groundworks and some roadworks.
• Suitability: Suitable for domestic and commercial projects
• Technical strength: 25N/mm2 – 25 Newtons per square millimetre after 28 days of curing

C30 Concrete

• What is C30 ideal for? C30 concrete is ideal for constructing pavements and a wide range of bases. A common, medium-strength mix, it can be used on driveways, garages and even patios.
• Suitability: Suitable for domestic and commercial projects
• Technical strength: 30N/mm2 – 30 Newtons per square millimetre after 28 days of curing

C35 Concrete

• What is C35 ideal for? C35 concrete is ideal for reinforced bases on commercial buildings as well as light storage areas in the commercial and agricultural sectors.
• Suitability: Suitable for domestic and commercial projects
• Technical strength: 35N/mm2 – 35 Newtons per square millimetre after 28 days of curing

C40 Concrete

• What is C40 ideal for? C40 concrete is ideal for creating septic tank foundations and for strong paving that can withstand heavy goods vehicles, farm vehicles and heavy traffic.
• Suitability: Suitable for commercial, agricultural and industrial projects
• Technical strength: 40N/mm2 – 40 Newtons per square millimetre after 28 days of curing

C45 Concrete

• What is C45 ideal for? C45 concrete is ideal for harsh environments, such as agricultural yards, slurry pits and HGV parks.
• Suitability: Suitable for commercial, agricultural and industrial projects
• Technical strength: 45N/mm2 – 45 Newtons per square millimetre after 28 days of curing

C50 Concrete

• What is C50 ideal for? C50 concrete is ideal for even the most extreme environments, withstanding abrasion and chemicals. This is a specialist mix for specific industrial sectors when stable foundations, roadworks and flooring are needed.
• Suitability: Suitable for commercial, agricultural and industrial projects
• Technical strength: 50N/mm2 – 50 Newtons per square millimetre after 28 days of curing

Talk to Madmix about concrete for your project

Whatever you need concrete for in Cambridge, St Neots, Huntingdon and the surrounding areas, don’t hesitate to talk to us if you need advice on the right mix for your application. We have over 20 years of experience so you don’t need to worry if you aren’t sure what technical strength you need — we’ll be able to make a recommendation and arrange for concrete delivery in your area.

For reliable concrete strengths and mixes from a trusted, independent company, get in touch today.