Building a barndominium includes many stages, including preparing the foundation. Most barndominiums are built on concrete slabs. Although a slab is less expensive compared to a full basement, you still need to consider the cost.
So, how much does a 1500-square foot concrete slab cost?
The national average price for a concrete slab is $4 to $8 per square foot. The median price is $6 per square foot. Based on the national average, a 1,500-square foot concrete slab may cost $6,000 to $12,000.
The average cost is based on certain details. Here is what you should know to accurately estimate the cost of your concrete slab.
What Does the Typical 1,500-Square Foot Concrete Slab Include?
A 1,500-square foot concrete slab will often measure six inches thick and include several other common features. The typical concrete slab includes the following standard features:
- 3,000 PSI concrete with a thickness of six inches
- 2×6 lumber for the wood form that acts as a frame
- Rebar around the inner perimeter for support
- Fiber mesh for reinforcing the concrete slab
- A contractor, labor, and necessary equipment
The average cost of a concrete slab is determined based on a slab with certain features. Choosing a thinner slab or a slab with thickened edges will influence the price. Some of the factors that may result in a higher or lower cost include:
- The thickness of the concrete slab
- Adding extra features for increased strength
- The local cost of materials and labor
- The need for site preparation
The cost of labor and building materials is not the same everywhere. Higher prices are often found on the West Coast and in the Northeastern United States. Lower prices are typically found in the Midwest and the South.
Another concern is the condition of the land where you want to build your barndominium. Basic site preparation work is included in the average cost of a concrete slab but does not cover extensive prep work. Removing trees, bushes, and other vegetation may add to your costs.
How Much Does a 1500-Square Foot Concrete Slab Cost Based on Thickness?
The estimate of $4 to $8 per square foot is for a six-inch concrete slab. However, slabs are available in several thicknesses. To help you compare options, here is the average cost for materials for different thicknesses:
- Four-inch concrete slab – $2.83 per square foot
- Five-inch concrete slab – $3.20 per square foot
- Six-inch concrete slab – $3.57 per square foot
A four-inch slab saves money compared to a six-inch slab due to the need for less material. You can save about $0.74 per square foot, which would lower the cost of a 1,500-square foot slab by about $1,110.
What Is the Cost of Adding Extra Features to a Concrete Slab?
Lowering the depth of the concrete slab may lower your costs, but you also need to consider reinforcing the concrete to prevent cracking. Some of the extra features available include:
- Thickened edges around the slab – $1 per square foot
- Adding a vapor barrier – $0.50 per square foot
- Extra wire mesh reinforcement – $0.40 per square foot
Choosing to include all three of these features can increase the cost of a 1,500-square foot concrete slab by about $2,850. If you choose a four-inch slab instead of a six-inch slab with these features, you may spend about $1,740 more compared to a standard concrete slab.
Should You Hire a Contractor or Pour the Slab Yourself?
A DIY concrete slab may cost about $2.40 less per square foot compared to hiring a contractor. Instead of using $6 as the average cost, you can use $3.60 to create an initial estimate.
You may spend about $5,400, saving around $3,600 compared to hiring a contractor. Yet, 1,500 square feet is a relatively large area. If you do not have experience pouring concrete, you should consider hiring a contractor.