Can You Pour Concrete Over Grass? (Find Out Now!)

What Happens When You Pour Concrete Over Grass?

To motivate yourself to put in those few extra hours of work to clear the area before you pour, here’s what can happen when you rush the job and pour concrete directly over grass:

If Not Grass, Then What?

Pouring concrete over grass can cause problems. So, what should the surface look like before pouring? When pouring a slab, three factors are imperative:

If these factors aren’t true of your surface, there are ways to make an ideal surface for your concrete pour.

How to Prepare the Ground for Concrete

Here are some steps to follow to prepare your ground before you pour your concrete.

Step 1: Remove the top layer of grass and dirt.

Generally, you want to have 2 to 3 inches of your slab below ground level and 1 to 2 inches above ground level. To do this, you will want to remove at least 3 to 5 inches of topsoil. If your ground is clay or the dirt tends toward moisture, you will want to remove another 2-4 inches to leave room for a layer of gravel or sand.

Step 2: Smooth the surface.

Using a rake, smooth out the surface of your newly cleared ground.

Step 3: Make sure the area is level.

You can use a leveler in key areas to check. Fill in any lower areas with dirt.

Step 3: Tamp down the soil.

Using either a hand tamper or a mechanical tamper, tamp down the soil. The soil needs to be well packed to ensure a stable surface for pouring concrete.

Step 4: Frame the edge.

Add a wooden frame for nice straight edges.

Step 5: Pour a layer of gravel.

When the area is cleared and tamped down, pour 2 inches of gravel on top. Tamp down the gravel layer for a smooth surface.

Step 6: Use rebar.

Add rebar to make your concrete as strong as possible.

Pouring Your Concrete

After you have prepared your ground, you are ready to pour your concrete. Most building codes nationwide agree that concrete slabs should be at least 3.5 inches thick. Many people choose to pour their slab thicker than the minimum standard for extra support. Here are some tips for pouring a concrete slab that will withstand years of wear and tear.

Step 1: Prepare and pour your concrete.

Follow the directions to make the proper concrete to water ratio. If your concrete is too thin, it can easily crack. If it is too thick, it can have difficulty setting up.

Step 2: Smooth the surface with a finishing trowel.

When you no longer see water on the surface of the concrete it is time to smooth it with a trowel. Move quickly so you can smooth the surface before it hardens.

Step 3: Allow your concrete the proper time to cure.

Concrete is stronger when it is allowed to cure slowly. It is important to allow the concrete to cure properly before using it. Most concrete will cure after 1 week.

Things to Consider Before Pouring a Concrete Slab

Concrete can be fairly straightforward if you are working on small projects. When it comes to larger projects, however, the stakes are greater. Before you decide to DIY a larger concrete slab or patio, here are some things to consider.

Not all concretes are created equal. Choose the right kind of concrete for the job.

There are many different kinds of concretes on the market that are used for different purposes. Make sure you are getting the right concrete for the job.

Make sure you have all the tools you need.

It can be expensive to buy concrete laying tools. See if you can borrow tools if you don’t own them.

Mix your concrete in the correct proportions.

Many factors go into the right water to concrete ratio including the heat index, humidity level, and more. Generally, it is better to err on the side of making thicker concrete.

Use steel reinforcement, especially for larger areas.

Large areas will usually need to be strengthened with rebar for lasting durability.

Use a moisture barrier when needed.

For outdoor areas, (such as patios and driveways) you generally will not need to lay down a plastic moisture barrier. If you plan to pour a slab for an enclosed structure, you will need to use a moisture barrier.

Count the costs.

After you add up the costs of concrete, rebar, wood frames, and tools, you can decide if it is best to DIY a large concrete project or to hire a professional.

Measure twice, pour once.

After pouring a layer of concrete, it will be there for a long time for better or for worse. Make sure to hammer out all the details before pouring to prevent expensive adjustments or replacements.