C20 Concrete Mix Ratio

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C20 Concrete Mix

Among the lightweight mixes we handle, GEN 3 / C20 concrete is the most commonly used. C20 concrete mix finds its application in a variety of projects, particularly on uneven surfaces. It holds a strength of 20 newtons after 28 days, and it sees frequent use in residential projects, with potential in select commercial uses as well.

Being a lightweight blend, GEN 3 / C20 concrete contains the highest cement content compared to other GEN concrete mixes. This characteristic adds to its adaptability, making it an easy-to-handle option suitable for various tasks.

  • Paving pathways and patios

  • Creating bases for sheds and garages

  • Constructing garage floors

  • Making unreinforced strip footings

  • Forming foundations for walls and single-storey structures

  • Crafting internal floor slabs that will be concealed

  • Suitable for both commercial and domestic purposes

However, using C20 concrete for the foundations of larger structures, such as extensions or other buildings that demand a sturdier base, is not advisable.

Important: Avoid using GEN3 externally unless it’s fully covered or enclosed.

Mix Your Own C20 Concrete

For C20 concrete, the correct concrete mix ratio is as follows:

  • 1 part Cement

  • 2 parts Sand (fine aggregate)

  • 4 parts Gravel (coarse aggregate)

If using premixed ballast, the concrete mix ratio becomes 6 parts ballast to 1 part cement.For optimal results, water should be around 55 percent of the cement’s net weight if all materials are perfectly dry. However, materials are often slightly damp, especially sand. In such cases, you might need to adjust the water quantity accordingly.

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Get Your C20 Concrete From Pro-Mix Concrete

Our experts have formulated the C20 concrete mix ratio to cater for a construction project that demands a dependable and high-quality base.

At Pro-Mix Concrete, we’re ready to deliver this concrete mix in the exact quantity you need. We’re committed to ensuring your project starts promptly. Using our volumetric trucks, we provide an on-site mixing service which means you receive the precise amount of C20 concrete needed for your project. This approach allows you to pay solely for the concrete utilized, leading to cost savings and reduced waste.

If you’re uncertain about whether GEN 3 / C20 concrete suits your needs, don’t hesitate to reach out to our team today. We’re here to offer assistance and guidance.

Understanding C20 Concrete Strength

Concrete strength is gauged in PSI (pounds per square inch) and newtons, reflecting the minimal compressive strength the concrete attains 28 days post-pouring. C20 concrete registers a PSI of 2900 or 20 newtons after this period, making it an optimal choice for residential tasks that demand a light duty mixture.

GEN 3 Or C20?

C20 and GEN3 concrete possess identical strength levels. GEN3 stands for General concrete grade 3 and is the same as Grade C20 concrete in terms of strength. The two, GEN3 and C20, signify the same concrete grade. In contrast to other concrete types, a C20 comprises double the amount of cement, whereas a typical on-site mix requires just one part of cement.

The C20 label represents the Concrete’s Compression Resistance strength. Specifically, for C20, this strength measures at 20 N/mm2 per square meter after 28 days.

Concrete comes in various grades with distinct resistances, ranging from C7 to C40. Among these grades, C7 is the least robust, while C40 can endure the highest pressure over an extended period. C20 occupies a middle ground on this scale, making it suitable for both domestic and commercial ventures.

Follow the standard 4:2:1 ratio to determine the necessary concrete amount. Combine four parts of coarse aggregate with two parts of fine aggregate and one part of cement. This formula yields the fundamental composition of C20 concrete. If you’re personally handling the mixing and pouring of C20, you can adjust the strength and texture as desired. This flexibility is among the advantages of on-site concrete mixing.

Don’t forget; our concrete calculator can assist in estimating the concrete volume you might require.

Certainly, any concrete can be made sustainable with the right materials. The process is simple. By using recycled aggregates sourced from demolition sites, you can run these materials through an industrial crushing machine. This machine breaks down the rock into a specific grain size tailored to your desired outcome. The crushed stone can even be turned into a fine powder for use as cement. Gravel and coarse aggregate can also be obtained by recycling building materials from demolition projects.

C20 concrete is ideal for lighter foundations and small-scale residential tasks, whereas C30 concrete boasts higher strength. That means the latter is suitable for applications like paving, hard standings, and house extensions.