Updated August 4th, 2020

You asked, **how much does a concrete slab cost?**

I can’t give an answer in a word.

Because there is no universal cost of a concrete slab.

There are many things involved.

But I can show you an easy process of calculating it.

Before that, let’s get some idea of a concrete slab.

## What Is A Concrete Slab?

A slab is a structural element of any structure. It can be a floor or a roof.

It’s supported by beams, columns, walls, or the ground.

If the concrete is used to construct a slab that is called a concrete slab. Often reinforcement is used in a concrete slab. When reinforcement is used that is also called an RCC (Reinforced Cement Concrete) slab.

The main ingredients of a concrete slab are **concrete **and **reinforcement**.

## Factors Affecting The Cost Of A Concrete Slab

As I told at the beginning of this post, there is no universal cost of a concrete slab.

Because there are many variables that can affect the cost of a concrete slab. You first need to understand those variables. Those are –

**Rate Of The Materials:**The rate of materials use to construct a concrete slab can differ in different places.

The materials price in my place isn’t the same as in your place. The price also varies in different seasons in the same place.

So the rate of materials used to construct a concrete slab has a big effect on the concrete slab cost.

**Rate Of Labors:**The rate of labors isn’t the same everywhere.

In some places, the rate of workers is much cheaper than in other places.

In a construction project, we normally don’t hire workers directly. We just hire a contractor.

The contractor provides manpower as needed. In that case, you need to know the unit rate for a concrete slab in your area.

**Centering And Shuttering Materials:**Besides slab ingredients, you also need some other construction materials for constructing a concrete slab. Such as formwork materials.

You can take them as rent or you can buy them.

If you buy, the concrete slab cost will be increased. If you take them from some rental service providers then the slab cost will be much less.

Buying or renting is totally depends on the size of your project.

If you are going to build just a concrete slab then renting is a wise decision.

But if you are constructing a new building project than buying these materials will reduce the cost of your project.

**Cost Of Machinery:**This is also the same, you can hire machinery or buy new depending on the size of your project.

**Location Of Your Project:**The project location also affects the cost. If your project is located in such a place where vehicles can’t access easily. Then the materials carrying cost will increase.

If the building materials and construction materials available near to your project then the carrying cost will less.

These things somehow affect the cost of a concrete slab.

## Step By Step Process For Calculating The Cost Of A Concrete Slab

It’s easy. You just need to go through the following steps:

### First, Estimate The Required Materials For The Slab

You’ll need to estimate the following things

- Required formwork materials
- Reinforcement
- Concrete volume

I’ve talked about how to estimate these materials before. Read the following posts –

How To Calculate Concrete Quantity For Slabs

How to Easily Estimate Shuttering Materials?

How to Estimate Beam Reinforcement?

How to make formwork for slab using only steel shutter material?

How to Calculate Materials For Different Ratio Concrete?

### Next, Collect Rates For The Materials

Collect rates for the following things –

**Formwork Materials:**Collect rates for the rent of formwork materials. Or the rates of formwork materials for buying.

**Collect Rate Of The Reinforcement**: Reinforcement is sold in tons or in kilograms. 1000 kilograms is equal to one ton. Collect the rate of a unit. If you’re going to construct just a concrete slab – not a building project- then you may want to buy the required size of rods. There are some companies that will supply rods as your required size and numbers. In that case, the rate may differ.

**Rate Of Concrete:**You’ll get ready mix concrete suppliers in your area. You can buy concrete from a supplier as a unit. The unit can be cubic feet, cubic yards, or cubic meters. Collect the rate per unit.

Sometimes, for some reason, you may want to prepare concrete on your project. In that case, you need to purchase concrete ingredients – Cement, fine aggregates, and coarse aggregates. Collect the rate of these materials individually.

**Rate Of Labor:**If you’re going to hire workers individually, you first need to estimate the required skilled workers, helpers, and unskilled workers for your project. And then, you need to collect the daily rate of them.

Another way is, you can hire a contractor for an area-base-unit basis. We normally hire contractors as square feet rate. In that case, you need to confirm the rate of the contractor per square unit.

You can also hire a contractor on a contractual basis. You just need to discuss a fixed amount for completing the task.

Here one thing you need to understand that when you hire a contractor on a contractual basis he’ll provide all the machinery required to complete the concrete slab. But if you hire workers individually you have to provide the machinery. So when you hire workers individually, you have to add the cost of machinery separately.

### Finally, Calculate How Much The Concrete Slab Cost

You now have everything to calculate the cost of your concrete slab. Take a piece of paper, a pen, and a calculator. Sum up the following things –

**Cost of Formwork:**Required formwork materials × unit rate = Amount**Cost of Reinforcement:**Required reinforcement × unit rate = Amount**Cost of Concrete:**Required concrete volume × unit rate = Amount**Labor Cost****Machinery Cost**(if required)

Sum up all these amounts and you’ll get the total cost of your slab.

As you know the total cost of your slab, you can now calculate the unit cost of the slab.

To do so, just divide the total cost of the slab with the total area of the slab.

If we want to express this with a mathematical term, it’ll be,

**The unit cost of a concrete slab = Total cost of the slab ÷ total area of the slab**.

Now let’s see…

## How Much Does A 12′x12′ Concrete Slab Cost?

Following the steps we outlined above…

### First, Estimate The Materials

**Formwork Materials:** Let’s say, we’ll take formwork materials from a rental service and they’ll charge as the slab-area-base unit. For example, They will charge **$1 **per square feet.

So, we don’t need to estimate the formwork materials individually.

But if you want to hire or buy these materials, you’ll need to estimate the materials individually.

**Reinforcement: **The reinforcement details of the slab is as the image below:

From the image,

Total number of bars,

= {(12′ ÷ 6″) + 1} × 2

= {(12′ ÷ ½′) + 1} × 2

= **50 nos**.

Length of a bar,

Let’s say 12 feet. If you want to calculate the more accurate way, you need to deep down. To keep this post short I took a simple way. I think you understand this.

So, the total length of the bars,

= 50 nos × 12′

= 600 feet.

= **114 kg**.

If you want to know how I convert the length of rods into kilograms, read the post – How to Calculate the Unit Weight of Steel Bars.

**Concrete Volume:**

From the above image –

The length of the slab, 12′.

The width of the slab, 12′.

And, the thickness is 6″.

So the volume of concrete of the slab is,

= 12′ × 12′ × 6″ [6″ = ½′]

= **72 cubic feet**.

### Next, Collect Rates For These Materials

Let’s say, we collected the following rates:

- Rate of Formwork – $1 per square feet of the slab

- Rate of Reinforcement – $0.75 per kilogram

- Rate Of Concrete: We’ll use ready-mix concrete and the rate is $3 per cubic feet.

- Rate Of Labor: Let’s say we hire a contractor to complete the concrete slab including, centering, shutting, reinforcement binding, and pouring concrete. The rate of all these work is $1 per square feet of the slab. The contractor will supply all the required machinery.

As we collected all the rates, let’s…

### Calculate How Much This 12′×12′ Concrete Slab Costs

- Cost Of Formwork: Slab area × unit rate = 12′×12′×$1 = $144

- Cost Of Reinforcement: Required reinforcement × unit rate = 114 kg × $0.75 = $85.5

- Cost Of Concrete: Required concrete volume × unit rate = 72 cubic feet × $3 = $216

- Labor Cost: Slab area × unit rate = 12′×12′×$1 = $144

So, the total cost of our example slab is,

= $144 + $85.5 + $216 + $144

= **$589.5**

Now let’s see…

## How Much Does This Concrete Slab Cost Per Square Foot

You can now calculate the cost of a slab per square feet.

Let’s take the above example.

The slab area is,

= 12′×12′

= **144 **square feet.

And, the total cost is,

= **$589.5**

So, the slab cost per square feet is,

= 589.5 ÷ 144

= $4.09

Say, **$4 **per square feet

You can also calculate the cost of slab per square meter.

Let’s see…

## How Much Does This Concrete Slab Cost Per Square Meter

In the above example,

The slab area is,

= 144 square feet.

= 144 ÷ 10.76 (1 square meter = 10.76 square feet)

= **13.38 **square meter

And, the total cost of the slab is,

= $**589.5**

So, the cost of this concrete slab per square meter is,

= $589.5 ÷ 13.38

= $44.06

Say, $**44 **per square meter.

**Conclusion**

Calculating the cost of a concrete slab isn’t a big deal. You first need to estimate the required materials, labors, and machinery and then collect their rates.

Once you have all these, you can easily calculate how much concrete slab costs.

Here I want to disclaim one thing that the rates I used in this post aren’t universal. I didn’t collect them from anywhere. So, you shouldn’t use those rates for calculating your slab cost.

But collecting rates isn’t difficult. You just need to visit materials suppliers or call them to collect rates.

*Now Your Turn*

*How do you calculate the cost of a concrete slab? Is there any easy way? Please share your experience in the comments below…*

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