How to Pour Concrete: A 10 Step Guide

Step 1 - Prepare the site

Taking the time to prepare the site carefully is a crucial part of the concrete process. It not only makes concrete placement easier but also ensures that the slab cures evenly and has uniform support.

Start by clearing the area of grass, roots, rocks, and debris to create a clean, stable surface. Excavate to the required depth, keeping the subgrade level and well-compacted to prevent concrete settling or cracking.

For sidewalks, driveways, and patios, add a 4-inch layer of gravel or crushed stone to improve drainage and provide extra support, then compact the subbase thoroughly with a hand tamper or plate compactor to ensure long-term stability.

Read more about subgrades and subbases for concrete slabs.

Step 2 - Install formwork

Once the base is prepared, install sturdy concrete forms to define the shape and dimensions of the pour. Position boards or reusable forms along the slab perimeter, anchoring and bracing them securely to withstand the pressure of wet concrete. Fasten the forms with stakes and screws, checking often with a level to ensure proper alignment and grade. Properly installed formwork not only defines the slab’s boundaries but also helps control thickness and slope for effective drainage.

Attention to detail at this stage pays off in the finished product. Gaps or misaligned forms can lead to uneven edges, bulging, or water pooling, while tight well-fitted joints produce clean lines and a professional appearance.

Step 3 - Add reinforcement

For most load-bearing slabs, reinforcement is essential for strengthening concrete and preventing cracks caused by shifting and settling. Steel rebar or welded wire mesh is commonly used to provide tensile strength, helping the slab resist stresses that plain concrete can’t handle on its own.

Distribute the reinforcement evenly across the prepared subbase, supporting it on chairs or blocks so it sits within the slab rather than directly on the ground. This positioning allows the concrete to fully encase the steel, protecting it from moisture and corrosion.

In addition to enhancing long-term performance, proper installation of rebar or mesh reduces the risk of costly repairs by helping the slab better withstand traffic, weather extremes, and everyday use.

Step 4 - Mix the concrete

For small DIY projects such as patios, walkways, or posts, using a bagged concrete mix is often the most practical choice. It comes preblended with cement, sand, and aggregate, requiring only the addition of water.

You can use a wheelbarrow, bucket, or portable mixer for mixing concrete, but consistency is key. Add water gradually and blend until the mixture has a uniform, workable texture. Too much water will weaken the finished slab and increase the risk of cracking, while too little makes placement difficult. (Learn more about the importance of using the right water-cement ratio.)

For larger jobs such as driveways or foundations, ready mixed concrete delivered by truck is the better option. Professionally batched at a plant, it ensures consistent quality and can be customized with admixtures for specific conditions. Ready mixed concrete saves time and labor, but should be placed promptly since it begins setting once batched and delivered.

Step 5 - Place the concrete in the forms

Once the concrete is mixed, shovel or pour the concrete directly into the forms until it reaches the top of the form boards. For larger projects, wheelbarrows, chutes, or concrete pumps can be used to move the material more efficiently. As you place the concrete, use a square shovel or a come-along (a specialized concrete rake) to spread the mix evenly and eliminate voids or air pockets.

Step 6 - Level and float the concrete

After concrete placement, strike off or screed the surface with a straight board or metal screed to bring the slab to the proper grade and ensure uniform thickness. Screeding compacts and consolidates the concrete while beginning the smoothing process, laying the foundation for all subsequent finishing steps.

Next, use a float to further compact the slab, fill voids, and even out high or low spots. A bull float is ideal for covering large areas quickly, while smaller hand floats work best for edges, corners, and detail work. Floating also draws a thin layer of paste to the surface, which helps create a smooth, workable finish. Read more about tools and techniques for concrete finishing.

Step 7 - Cut control joints

At this stage, while the concrete is still plastic but firm enough to hold its shape, cut control joints with a groover to help manage cracking. At the same time, run an edger along the slab’s perimeter to create clean lines.

Cutting control joints while the concrete is still plastic ensures that they form cleanly without tearing the surface. If you delay jointing until after the slab has hardened, the joints must be saw-cut instead. This is typically done within 6 to 18 hours of placement, before shrinkage cracks have a chance to develop.

Step 8 - Trowel the surface

Once the concrete has set enough to support your weight without leaving deep footprints, you can begin troweling to smooth and densify the slab. The exact timing depends on factors such as humidity, temperature, and the concrete mix. But if the slab is allowed to harden too much, effective troweling becomes nearly impossible.

Using a steel hand trowel or fresno (a steel trowel attached to a long handle) work in sweeping, overlapping strokes to create a uniform finish. For large projects, such as long driveways or commercial slabs, power trowels can be used, moving in overlapping passes to ensure consistent coverage.

The troweling process is typically repeated several times, with pressure reduced on each successive pass to refine the surface. Because troweling is as much an art as a technique, using the right tools and methods is essential to achieving a durable, professional-looking finish.

Step 9 - Perform final finishing

Once troweling is complete, the final finish can be applied to the concrete. The type of finish often depends on the slab’s intended use and should balance appearance, durability, and safety:

• A smooth steel-troweled finish produces a dense, polished surface that works well for interior floors but may be too slippery for outdoor slabs.
• For exterior applications such as sidewalks, patios, and driveways, a broom finish is often preferred because it adds texture and slip resistance.
• If a more distinctive look is desired, consider applying a decorative finish, such as exposed aggregate or stamped concrete, to create greater visual appeal.

Step 10 - Allow the concrete to cure

In the first week or so after concrete is poured, it’s essential to maintain the proper temperature and moisture to ensure full hydration. Without adequate curing, the slab can dry too quickly, leading to surface cracking, reduced strength, and long-term durability problems.

There are several effective curing methods you can use to maintain optimal moisture levels for proper curing, including wet curing, coverings that trap moisture, and the application of a curing compound. The best approach often depends on project conditions, the climate, and practicality.

While it generally takes about 28 days for concrete to fully harden and attain maximum strength, the most critical period for curing is the first 7 to 10 days.