Concrete Slab

Whether you wish to install a concrete driveway, patio, or even sidewalks, you must correctly prepare the ground before laying the concrete. As such, ensuring the surface of a concrete slab remains level may be best done by correctly designing the subsurface. If this is done, you can avoid getting your concrete damaged rapidly and manifesting a variety of surface defects. To this end, several ways to properly level the ground require some fundamental equipment and effort.

So long as you find the time to level the ground and create a solid base, your concrete will withstand time without cracking or sinking. On the other hand, should you feel you aren’t up to the task, enlisting a seasoned Concrete Contractors Omaha, NE, professional is always prudent. Such a contractor can prepare the ground correctly to ensure your concrete will be built to last. With that fully understood, here is a step-by-step guide on leveling the ground before constructing a concrete slab.

Consult utility firms to determine if there are subterranean lines beneath your property.

Before doing anything else, first take the time to contact your electricity, gas, and water providers to alert them you wish to dig into your property. In most cases than not, reputable utility firms will be more than willing to dispatch someone to check for pipes or lines and notify you whether it is safe to dig. Should any pipes or tubes traverse the area you want to lay your concrete slab, consider choosing another location to avoid causing damage to such underground utility locating services.

Mark out a rough outline for the concrete slab

When you get the go-ahead to dig, take all the time you need to lay a rope on the ground to mark the area the slab will occupy. Whenever you arrive at a corner, bend the string and continue to outline the slab’s shape. Once this has been accomplished, drive stakes 1 foot away from every corner of the rope outline. This will ensure that the stakes remain aligned with one side of the system. Using a hammer, drive the stakes deeply into the ground and leave no more than 8” sticking out. Repeat this process for all outline corners to form a rectangular shape. When you place the stakes, you may remove the rope. Try as much as possible not to put the stakes at the places where the corners of your slab will be positioned. This is simply because you must level the ground beyond the slab’s perimeter to prevent it from sinking.

When it comes to preparing the ground for a concrete project, proper leveling is essential for ensuring a stable and long-lasting foundation. One company that has extensive experience in this area is Dobson Excavations Perth, which can provide expert guidance and services to ensure your project gets off to a strong start. By working with skilled professionals like them, you can ensure that your construction project is built on a solid foundation, setting the stage for success.

Tie a mason’s string around the stakes to outline your concrete slab’s perimeter.

Generally speaking, measure between 2” to 3” beneath the tops of the stakes and then tie some mason’s string around them. First, start by pulling the line straight towards the stake directly across the one you first tied to mark the concrete slab’s side. Next, use a new mason’s string and link the stakes on the other side, ensuring it will intersect the first piece of string you tied. The corner of the slab is where the 2 lines cross each other. Lastly, ensure you secure the series at a similar height on all stakes to allow them to remain level. If you need to do so, you can draw lines 2” to 3” down from the upper parts of the stakes to form a reference mark.

Slope the strings way from the foundation of your home.

Always try to avoid making the concrete slab flat if it is directly next to your house, as water might pool on its surface and cause damage to it. To which end, determine the length of the slab’s side in feet and then multiply the figure by 1/8 to arrive at the suitable slope in inches. Determine the 2 stakes which are further from your house, and then adjust the mason’s strings down by the measurement you reach. For instance, if the side of the slab is 14 feet, then multiple 14 x 1/8 is equal to 1¾ “.

Excavate the site where you want to install a concrete slab.

First, take as much time as you require to do away with the grass and sod in the area surrounded by the stakes. You may use a shovel to break the ground’s surface, which will allow you to remove the grass hassle-free. Then, drag the clumps off the ground to expose the soil beneath. Ideally, leave no less than 4” of grass between the stakes and the edges where you have dug. Continue to dig out the area until it is no less than 6” below the strings. Begin at the outer edges and work your way toward the center of the hole. This will go a long way in making it even easier to ensure the hole depth is consistent. Should there be tree roots or big stones within the soil, eliminate them too. As you proceed to dig, ensure the depth from the strings to the ground is no less than 6”. While the lines mark the outer edges of the slab, dig 6” out of them. This will ensure you create a more extensive base to avoid the slab sustaining damage with time. Next, rake the soil to fill low spots. Flip the rake upside down with the tines pointing upwards and proceed to drag it to flatten raised scars and fill in any holes you dug too deeply.

Compact the soil with a tamper.

Position the tamper in the hole's corners and press it flat using your weight. Also, move it over to ensure it overlaps the first section by at least 2” before pressing it down again. Work your way through the entire hole until its surface is even. If you fail to tamp the soil, your concrete slab might sink deep into the ground as it starts to settle. Lastly, determine if the earth is flat by using a level.


Fill in the sub-base.

Use gravel to fill in the hole and then spread it evenly across the perimeter of the hole. You may utilize a shovel or a rake to evenly distribute the gravel in the spot. Keep adding the stone until it is no more than 2” from the upper part of the hole. Next, use a garden hose to wet the stone. Doing this makes the more diminutive pieces of the stone sink deep, making the subbase more compact. You should then compress the subbase using a tamper. Finally, use a level to determine whether the subbase is perfectly centered. If not, continue pouring in more gravel and tamping it to raise the low spots. When the ground is level, you can then pour the concrete.