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

How Much Does a 30x30 Concrete Slab Cost

Most barndominiums are built on concrete slabs. A slab foundation costs less compared to other types of foundations but may still add several thousand dollars to the total construction costs.

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

Pouring a concrete slab may cost between $4 and $8 per square foot, with an average cost of $6 per square foot. Based on the national average, a 30×30 (900 square feet) concrete slab may cost about $5,400 (900 times 6 = 5,400).

What Do You Get with the Typical 30×30 Slab?

The average price of $6 per square foot is based on a concrete slab with the following features:

  • A wood form made from 2×6-inch lumber to support the slab
  • Six inches of 3,000 PSI concrete with 3/4-inch crushed stone
  • Fiber meshing in the concrete for extra reinforcement
  • A row of rebar added around the inside perimeter of the slab
  • Labor to pour and finish your concrete slab

Yet, the concrete slab costs may vary depending on where you live and whether you decide to pour the slab yourself.

How Much Does a 30×30 Concrete Slab Cost?

Building cost factors

The average cost includes material and labor. However, not everyone uses the same material or hires labor. The main factors that determine the cost of a 30×30 slab include:

  • The thickness of the slab
  • Site preparation
  • Extra features
  • Local costs for material and labor

The thickness of the slab influences the total cost, as a thicker slab requires more material. Here is the base price for concrete based on thickness:

  • 4 inches – $2.83 per square foot
  • 5 inches – $3.20 per square foot
  • 6 inches – $3.57 per square foot

You may also need to perform extra site preparation work, such as leveling the ground or removing tree stumps. The average cost to prepare the area under the slab is about $0.60 to $1.25 per square foot.

Instead of a basic slab, you may choose to include extra features. Here are some of the features that may increase the price of pouring a 30×30 slab:

  • Reinforced wire mesh – $0.40 per square foot
  • Thicker edges – $1 per square foot
  • Styrofoam layer under the slab – $2 per square foot
  • Vapor barrier – $0.50 per square foot
  • Textured or colored concrete – $4 per square foot

Reinforced wire mesh, thicker edges, and vapor barriers are common features for barndominium foundations. Reinforced wire mesh and thicker edges increase the strength and longevity of the slab. A vapor barrier protects the slab from moisture, which also helps increase its life.

Material and labor are typically evenly divided. The national average of $6 per square foot includes about $3 for material and $3 for labor. However, the cost of material and/or labor vary across the country.

For example, the cost of labor is up to twice as high in coastal states compared to areas of the southeast. Massachusetts, New York, Washington, and California have some of the highest labor and building costs.

How Much Does a DIY 30×30 Concrete Slab Cost?

If you decide to pour the slab yourself, you may cut the average cost by up to 50%. A four-inch slab costs $2.83 per square foot. If you decide to add wire mesh, thick edges, and a vapor barrier, you may pay about $4.83 per square foot for the material.

At $2.83 per square foot, a 30×30 concrete slab costs $2,547. At $4.83 per square foot, a 30×30 concrete slab costs $4,347. To get an estimate of the cost of pouring concrete, you can use a concrete slab calculator to help determine costs.

High and Low Estimate for Installing a 30×30 Concrete Slab Foundation

The lowest price for a 30×30 concrete slab is about $2,547 if you decide to build it yourself. Hiring a subcontractor to install a concrete slab with a vapor barrier, mesh, and thicker edges may cost up to $7,200.

The factors that affect the pricing that were given in this article should help guide the builder and/or owner to answer the question ‘How Much Does a 30×30 Concrete Slab Cost?’.