Concrete Mix Ratios | Understanding All Mixes for All Concrete Projects. Whether you’re a DIY expert looking to learn more about concrete mix ratios to line your driveway, garage or workshop, or a seasoned concrete contractor looking for the best mix ratios, Concrete Flooring Solutions has the answers to both needs.
Understanding concrete mix ratios is essential to ensure you’re creating the right mix for your environment and project. This will help you get the msoe use out of your flooring or structure and ensure a long-lasting and safe structure.
What is the best concrete mix ratio?
We’ll go into the ins and outs of mix ratios in more detail below, but to simplify, a good concrete mix ratio for a concrete floor is:
1: cement 2: sand 4: coarse aggregates (for concrete slabs)
When mixing, it’s important that the concrete is placed within half an hour to ensure consistency and easy placement. This should be done using a square-headed shovel for ample placing and a smooth finish.
What is a Concrete Grade?
Simply put, concrete grade is the absolute minimum strength the concrete must harbour 28 days after its construction. You will need to understand the acronyms behind the grading formula to understand your mix ratios. We’ve simplified this for your convenience below:
- M – stands for mix
- MPA – MPA stands for megapascal, which measures the compressive strength of the concrete. Concrete contractors will measure MPA to understand how much pressure can be applied to the concrete without it cracking or failing. Simplified, MPa tells us the overall strength of the concrete.
- PSI – all concretes come with different strengths, compositions, applications and types. We measure a concrete’s compression in pounds per square inch (PSI). most concrete compositions have a PSI range of between 2,500 and 5,000.
Putting it into practice:
Let’s use this in an example, for M5 concrete, the mixing proportion would be 1: (cement) 5: (sand) 1: (coarse) 0: (aggregates). The mix will always consist of cement, sand, water and aggregates.
Base Concrete provide a helpful table that outlines all concrete mix ratios:
| Concrete Grade | Mix Ratio (cement : sand : aggregates) | Compressive Strength | |
| MPa (N/mm2) | psi | ||
| Grades of Concrete | |||
| M5 | 1 : 5 : 10 | 5 MPa | 725 psi |
| M7.5 | 1 : 4 : 8 | 7.5 MPa | 1087 psi |
| M10 | 1 : 3 : 6 | 10 MPa | 1450 psi |
| M15 | 1 : 2 : 4 | 15 MPa | 2175 psi |
| M20 | 1 : 1.5 : 3 | 20 MPa | 2900 psi |
| Standard Grade of Concrete | |||
| M25 | 1 : 1 : 2 | 25 MPa | 3625 psi |
| M30 | Design Mix | 30 MPa | 4350 psi |
| M35 | Design Mix | 35 MPa | 5075 psi |
| M40 | Design Mix | 40 MPa | 5800 psi |
| M45 | Design Mix | 45 MPa | 6525 psi |
| High Strength Concrete Grade | |||
| M50 | Design Mix | 50 MPa | 7250 psi |
| M55 | Design Mix | 55 MPa | 7975 psi |
| M60 | Design Mix | 60 MPa | 8700 psi |
| M65 | Design Mix | 65 MPa | 9425 psi |
| M70 | Design Mix | 70 MPa | 10150 psi |
Breaking Down Each Design Mix
In order to get the most out of your construction project and concrete floor, you must understand what design mix is the most suitable and appropriate for your needs. Below, we have separated each concrete mix by the settings in which they’re used in (domestic or commercial).
Choosing the right concrete mix ratio is essential in order for you to not only get the most out of your concrete, but to ensure it lasts the test of time and looks aesthetically-pleasing in its environment.
Concrete mixes for commercial settings
So what can these grades be used for and which is best for the job at hand? Below is a list of a few of the initial concrete grades and what they are best used for.
C10 Concrete
Environment: Domestic & commercial
What is C10 concrete used for? Predominantly patio slabs, pedestrian pathways and domestic outdoor work
C15 Concrete
Environment: Domestic and commercial
What is C15 concrete used for?: Most C15 concrete is used to line curbs and floor bindings and is typically used in domestic settings but can be used in small commercial projects.
C20 Concrete
What is C20 concrete used for?: C20 is a fantastic option for contractors looking to build strong and durable floor foundations. C20 has a high strength level and is able to support the weight and abuse of everyday foot traffic, machinery and heavy duty working. This makes it ideal to line garages, driveway and workshop floors.
Environment: Mostly domestic
C25 Concrete
What is C25 concrete used for?: One of the most versatile concrete mix blends. C25 can be used in almost any concrete construction requirement but is most commonly used in building foundations and flooring.
Environment: Both domestic and commercial
C30 Concrete
What is C30 concrete used for?: the lowest grade concrete use in the construction of roads, driveways and heavy duty flooring. C30 concrete is designed to withstand constant vehicle traffic as well as weather. This type of concrete lines motorways in the UK.
Environment: Commercial
C35 Concrete
What is C35 concrete used for?: again a very durable concrete that is hard-wearing and able to withstand and support constant pressure. Unlike C30, C35 is mainly used to create external walls to support buildings and structural pilings. C35 concrete can be found supporting multi-storey car parks.
Environment: Commercial (usually large scale projects)
C40 Concrete
What is C40 concrete used for?: C40 is used to create strong, supporting beams and foundations for huge buildings and heavy traffic roads. C40 concrete is the strongest and most durable mix and for good reason townhomes for sale san diego. It can handle almost any abuse, including withstanding corrosion, making it ideal for farm-based and laboratory environments.
Environment: Commercial (usually large scale projects)
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