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How Much Does a 20×30 Concrete Slab Cost? | Pricing Important Factors

How Much Does a 20x30 Concrete Slab Cost?

Constructing a barndominium involves many stages. After clearing the land, you can start work on your new barndominium. The first step is to pour a concrete slab, as you need a foundation for the frame.

With a 20×30 barndominium floor plan, you may need a 20×30 slab foundation.

So, how much does a 20×30 concrete slab cost?

The average concrete slab costs are between $2,400 and $4,800. The median price is about $3,600. However, the thickness of the slab and other features may increase or lower the cost. Here is a closer look at the costs involved in adding a 20×30 concrete slab.

What Does the Average 20×30 Concrete Slab Include?

Not all slabs are the same, which is why the cost of your foundation may not match the national average. People typically pay between $4 and $8 per square foot to hire a contractor to pour a slab foundation with the following features:

  • 3,000 PSI concrete poured to a thickness of six inches
  • Fiber mesh reinforcement to increase the strength of the slab
  • 2×6-inch lumber to create a wood form around the slab
  • Rebar for added support around the perimeter of the slab
  • A contractor and laborers to pour and finish the slab

If you choose a different thickness or add special features, the cost is likely to change. Some of the main considerations when determining the cost of a 20×30 slab include:

  • Thickness
  • Features
  • Region

The region that you live in has a significant impact on average costs. You pay more for labor and materials in certain states. For example, Hawaii, California, and Washington are among the most expensive states. Alabama, Oklahoma, Mississippi, and Nebraska offer some of the lowest prices.

How Much Does a 20×30 Concrete Slab Cost Based on Thickness?

The average cost of $4 to $8 per square is based on the cost of a six-inch-thick concrete slab. A four-inch-thick foundation may save close to $0.75 per square foot.

Here is the average cost for the material to pour concrete:

  • 4-inch slab – $2.83 per square foot
  • 5-inch slab – $3.20 per square foot
  • 6-inch slab – $3.57 per square foot

You may pay about $1,698 on material for a 20×30 slab that measures four inches thick. The material for a six-inch slab may cost closer to $2,142.

If you plan on hiring a contractor, the cost of a four-inch-thick slab is about $4 per square foot, resulting in a price of $2,400 for a 20×30 slab.

Average Cost of Extra Features for a Slab Foundation

The slab that you pour will likely hold more weight compared to a slab for a patio or walkway. To ensure that your foundation holds up for decades to come, you may include several extra features for increased strength, including:

  • Thick edges – an extra $1 per square foot
  • Vapor barrier – $0.50 per square foot
  • Reinforced wire mesh – $0.40 per square foot

These three features may add about $1.90 per square foot to your total costs. Yet, these features may also extend the life of your foundation.

For a 20×30 slab, adding thicker edges, a vapor barrier, and wire mesh may cost an additional $1,140.

vapor barrier for concrete slab

DIY Versus Hiring a Contractor for a 20×30 Concrete Slab

Choosing to pour the concrete slab yourself saves money, as you do not need to pay for labor. The cost of the material alone is between $1,698 and $3,282, depending on thickness and other features. To get an estimate of the cost of pouring concrete, you can use a concrete slab calculator to help determine costs.

Hiring a contractor to pour a 20×30 foundation with all the features listed above may cost up to $4,800. However, hiring professionals provides peace of mind, as you are less likely to experience cracks and other structural issues.

It is now easier to estimate the cost of a 20×30 Concrete Slab considering the different factors that affect its price. With that, we hope to have answered the question- How Much Does a 20×30 Concrete Slab Cost?