How Much Does a 16×20 Concrete Slab Cost in 2024?

A concrete slab is vital to most construction projects because of its versatility. You can use a concrete slab as flooring or foundation. You can also turn it into a base for your grill or bench. If you’re looking for flooring for a two-car garage, a workshop, or a shed, a 16×20 concrete slab is just the right size. 

Before making your 16×20 concrete slab, it is essential to know how much it will cost. The answer varies and depends on other factors, like how thick the slab is and if you want additional features. It would be best if you also considered the prevailing prices of building materials in your area, like cement, sand, gravel, and reinforcing bars.

In this article, we will tell you more about concrete slabs and also teach you how to compute the price of a 16×20 concrete slab so you can prepare an accurate budget.

What Factors Determine the Cost of a 16×20 Concrete Slab?

When computing the cost of a concrete slab, you need to consider several factors. The size of your concrete slab is the first thing you need to consider. A 16×20 concrete slab will have a total area of 320 square feet. It is not as large as a 15×30 concrete slab, so expect it to be cheaper. The size of your slab is important because it dictates the number of building materials you will use. 

Your location is another factor because you might be in an area where building materials are expensive. Aside from the cost of materials, your location also affects labor expenses. Some areas have higher labor rates, so you might need to pay more if you hire a contractor. 

How Much Does a 15×30 Concrete Slab Cost?

As mentioned earlier, the cost of your concrete slab may change depending on several factors, so let’s look at some sample cost estimates using different variables. 

Per Thickness

Concrete slabs don’t have a uniform thickness. Some slabs are thicker because they need to bear heavy loads like those used as driveways for pole barn homes  or barndominium foundations. Other concrete slabs can be thinner, like those used as walkways or as foundations for garden benches. Thicker concrete slabs are more expensive because they require more materials. 

Thickness	Cost per square foot
4 inches	$5.35
5 inches	$5.80
6 inches	$6.20
8 inches	$7

Inclusions

Concrete slabs have inclusions, and these can affect how much you need to spend on your 320 square foot concrete slab. Inclusions are those that you will need to create a basic concrete slab. An example of inclusion is the rebar you will use to reinforce the concrete slab.

To make the concrete slab yourself, you need a one-bag concrete mixer to help you work faster and thoroughly mix your concrete. You can rent a mixer from a local rental company. Buying one might be more practical if you have other DIY construction projects. 

Inclusion	Cost
Cement Mixer	Prices start at $439 (2)
Concrete Mixer Rental	$97 per day (3)
Concrete Rebar	$1.40 – $1.85 per 2 feet (4)
Wire Mesh	$0.28 per square foot (5)

With Additional Features

Although the most common concrete slabs are plain, there is also the likelihood that you will use a concrete slab with additional features. For example, if you plan on using a concrete slab as a walkway, it will be better to use a textured concrete slab since it is safer to walk on because it provides grip.

A textured concrete walkway is safer because it can prevent slips and accidental falls. Also, consider using stamped concrete since it looks better and can resemble natural stone, tile, or wood. If you use concrete slab flooring for your basement, adding a vapor barrier can prevent moisture, so your basement stays dry. 

Features	Cost
Vapor barrier	$0.50-$0.70 per square foot (6)
Stamped concrete	$9 – $20 per square foot, inclusive of materials (7)
Stained concrete	$2 – $4 per square foot, staining only (8)

16×20 Concrete Slab Cost Breakdown

Let’s take a look at the cost of the individual components of a 16×20 concrete slab. 

Concrete Bag Cost Estimate

Concrete mix is the primary component of a concrete slab. A bag of concrete mix can cost $4.50- $27 depending on the size of the bag and type of mixture ⁽⁹⁾. 

Labor Cost Estimate

Labor expenses can set you back around $2-$3 per square foot ⁽¹⁰⁾. You can save money by making the concrete slab yourself, but it is not advisable if you haven’t done it before. 

Truck Cost Estimate

Ordering wet concrete is an excellent alternative if you want to save time or don’t want to mix your own concrete. It can also ensure that you use the proper mix if you haven’t made a concrete slab before. Concrete delivery costs $125 – $133 per cubic yard ⁽¹¹⁾.

These rates are inclusive of the materials and the delivery fee. The amount of concrete you need will depend on the size of the slab indicated in your floor plan. 

How Do You Calculate the Cost of a 16×20 Concrete Slab?

Now that we’ve discussed everything you need to know about computing how much a 320 square foot concrete slab costs, let’s look at several price cost averages of a 16×20 concrete slab. These will give you an idea of the price range you will work on as you create a budget for your concrete slab. 

Using this calculator, you can see that a 6-inch thick concrete slab measuring 16×20 requires 5.926 cubic yards of concrete. We will add 10% to this figure to make up for wastage, so you’ll need 6.52 cubic yards of concrete for your 320 square feet concrete slab.

The average cost of concrete for 2022 is around $137/cubic yard, as per data from the National Ready Mixed Concrete Association ⁽¹²⁾. This means a concrete slab measuring 320 square feet should cost around $895. 

You can also compute the cost of your concrete slab on a per-square-foot basis. We’ve already established that a 16×20 concrete slab has a total area of 320 square feet. In addition, we already know that the average cost for a 6-inch thick concrete is $6.20/sq. Ft. ⁽¹⁾. This means that a 320 square foot concrete slab should cost you around $2,183, including the 10% waste allowance. 

Should You DIY or Hire a Contractor for Your 16×20 Concrete Slab Project?

Hiring a contractor is the best way to make your 16×20 concrete slab, especially if you haven’t poured concrete before. An expert can make sure that the concrete mixture is correct and that your slab will be durable. An expert builder can also complete the task quickly while you focus on other aspects of your construction project. 

Conclusion

Knowing how to compute the cost of a concrete slab is important, especially if you want to get an accurate picture of how much your shed, garage, or shop will cost. You can use the information above to check your 16×20 concrete slab’s cost if you want additional features. The computations above will also come in handy if you want to ensure that a contractor is not overcharging you for a 320 square foot concrete slab. Like and follow our Facebook page for more informative articles about, barndominium financing, insurance, and barndominium costs.

  

References

1. How Much Does A Concrete Slab Cost In 2023? Homeadvisor.
2. Cost Of A Concrete Driveway ConcreteNetwork
3. What Are Common Rebar Prices for Concrete Projects? Angi
4. How to Compare the In-Place Cost of Wire Mesh Versus Synthetic Fibers ABC Polymer Industries
5. How Much Does Crawl Space Encapsulation Cost? Angi 
6. Stamped Concrete Cost For Patios, Driveways & More ConcreteNetwork
7. Concrete Floor Cost – What You’ll Pay For Polished Or Stained Concrete ConcreteNetwork
8. How Much Does Concrete Cost? Angi
9. How Much Does a New Concrete Slab Cost? Angi
10. How Much Does It Cost to Have Concrete Delivered in Your Area? Fixr
11. Ready Mixed Concrete Industry Data Survey. NRMCA