Concrete slabs are common elements in almost any construction project. Whether you’re building a barndominium, shouse, pole barn, or shipping container home, you will most likely need to make a concrete slab. You can use a concrete slab as flooring, roof(deck), driveway, or footpath. Since there is a great possibility that you will make a concrete slab along the way, you must know how much it will cost to make one.
This article explains the cost of making a concrete slab and the various factors affecting its cost. We will also give you some amazing tips to help you minimize costs and save money during construction.
Table of Contents
How Much Does a Concrete Slab Typically Cost?
Per Size
The table above shows the costs of the various sizes of concrete slabs. The first and second columns show the size of the slabs and their total square footage, while the third column shows the estimated costs of each slab.
The estimated costs were computed by multiplying the total square footage of each slab by the cost of a square foot of concrete slab. We also added a 10% waste allowance on top of the computations to give you some wiggle room.
Per Project
The cost of a concrete slab can differ depending on your project. Here are some sample projects that require making concrete slabs.
Driveway
If you are making a driveway, you need a thick concrete slab. This can help ensure that your slab won’t crack with daily use. A 4-inch thick concrete slab driveway costs $5.35 per square foot. You can go for a thicker driveway using a 5-inch thick concrete slab costing $5.80 per square foot.
Patio
For a patio, a concrete slab that’s 6 inches thick should be enough to handle foot traffic. Expect to pay $6.20 per square foot of concrete.
Countertop
If you are making a countertop, you can use a concrete slab between 1.5 inches and 3 inches thick. You can top it off with granite or butcher block for reinforcement.
How Do You Calculate the Cost of a Concrete Slab?
There are several ways to calculate the cost of a concrete slab. The method you will use differs depending on how you plan on making the slab.
The first method you can use is when you want to calculate costs depending on the amount of concrete you will use. The most common thickness of concrete slabs for residential structures, like barndominiums and pole barn homes, is six inches. A six-inch thick concrete slab should be more than enough to support the weight of your barndo or pole barn home. You can use this calculator to determine how much concrete you need for any given project. Just input the length and width of the concrete slab, as well as its thickness.
Let us use a 50×50 concrete slab as an example. According to our calculator, a 50×50 concrete slab needs 46.296 cubic yards of concrete. To be safe, we will add a 10% waste allowance to this figure. Since you have an allowance, you will still have enough concrete to use, even if you accidentally spill some while making the slab. With the addition of the 10% waste allowance, the total wet concrete volume you will need is 50.93 cubic yards.
The National Ready Mixed Concrete Association estimates that a cubic yard of concrete costs around $137 per cubic yard. This means that 50.93 cubic yards of concrete will cost $6,977.41. This estimate is just for the cost of concrete and does not include labor costs and other materials, like rebar, wooden form, or wire mesh. Use this calculation only if you want to estimate the cost of concrete, such as if you are doing a DIY concrete slab or if you have a contractor providing you with the manpower.
If you plan on hiring a contractor to make the slab, you can compute costs on a per-square-foot basis. A six-inch thick concrete slab costs around $6.20 per square foot. Using a 50×50 concrete slab as a reference, the total square footage of your slab is 2,500 sq. ft. We will multiply the total area by $6.20, so it will cost you $15,500. We will increase this figure to $17,050 by adding our 10% waste allowance. Note that this computation includes labor and the cost of materials, so you should use this computation if you plan on contracting the slab construction.
What Factors Affect the Cost of Concrete Slabs?
Even if several concrete slabs are the same size, you will notice they might have different costs. This is because many factors affect pricing. This section will help you understand these factors and how they drive the costs of concrete slabs.
Type of Mixture
The type of mixture you will use will also affect the cost of your slab. For example, a 1:2:3 mixture contains 1 part cement, 2 parts sand, and 3 parts gravel plus ½ part water. You can increase or decrease the parts for sand and gravel, depending on the strength of the concrete you need and how you will use your concrete slab. It will be best to consult your contractor on the mixture type to use since they know which type will suit your needs best.
Size and Thickness
The size of a concrete slab is the most important factor when computing costs. A large concrete slab costs more to make because it uses more materials. Aside from concrete, you will need more rebar, wire mesh, and a larger wooden framework.
Receive Quotes from Multiple Barndominium Builders & Kit Providers Near You Today (It's Free!)
Fill in this 1-minute form below and receive estimates for your project without having to find them yourself! Let them do the work.
Thickness is another factor you need to consider. The thicker the concrete slab is, the more materials you need. However, while a thick slab is more expensive to make, it is also more durable and can last longer. This means that thick slabs might be more expensive to make, but you will be getting your money’s worth in terms of longevity.
We mentioned earlier that six inches is the usual thickness of concrete slabs. Why would you need a thicker slab, then? If the slab is intended to support much weight, you need a thicker one. For example, a thick slab is advisable if your garage houses large vehicles and heavy machinery. A thick slab can support the weight of your vehicle without cracking or deforming.
Another example is if you are making a concrete slab roof to have a functioning roof deck. A thick slab is required to support the weight of furniture on your roof deck and the people staying there. A thinner slab should be more than enough for non-load-bearing slabs like pavements and garden footpaths.
Reinforcement
Reinforcing a concrete slab is a critical step if you want to ensure that it is durable and can support heavy loads. Reinforcement can help increase the tensile strength of a slab. The most common reinforcement for concrete slabs is reinforcing bars or rebar. You need to position reinforcing bars across the entire concrete slab at regular intervals and tie them together using reinforcement ties. Rebar costs between $1.40 and $1.85 per two feet.
A wire mesh is a suitable alternative to rebar for thinner concrete slabs. It can help increase the tensile strength of a thin slab to support the weight of a person, a garden chair, or a barbeque grill. Wire mesh costs $0.28 per square foot.
Labor and Equipment
If you don’t plan to make a DIY concrete slab, you need to consider labor expenses. A concrete slab can cost you $2 to $3 per square foot in labor costs. However, these estimates can change depending on your location because labor rates can vary from one location to another. Rates can also change depending on the credentials and qualifications of your contractor. Veteran contractors with years of professional experience and an impressive portfolio of projects often command higher rates than less-experienced contractors.
If you want to make a concrete slab, you need to arm yourself with the proper equipment. A cement mixer is one such piece of equipment. A cement mixer can help ensure that you can thoroughly mix concrete for your slab. In addition, using a cement mixer can help you work faster than manually mixing concrete. This can help you save time so you can complete the slab quickly. A one-bag cement mixer should be enough for smaller projects; you can rent one daily. If you have other construction projects planned, buying a cement mixer might be more cost-effective than renting.
Additional Features
Bare concrete slabs cost the same, provided they are of the same size and thickness. However, there are instances when you need additional features in your slab. The features will depend on how you want to use your slab. For example, if your floor plan includes a basement, you might consider adding vapor barriers.
Basements are notorious for being moisture magnets. This can lead to serious issues because moisture promotes the growth of mold and mildew. Fungal growth can lead to wood rot which can damage the structural integrity of your building.
Mold and mildew can also lead to health issues. Mold and mildew have spores that can trigger allergic reactions like watery eyes, sore throat, itchy skin, and runny nose. Prolonged exposure can also lead to more serious issues with the respiratory system, like asthma.
A concrete slab flooring is excellent if you want a cheap alternative to tiles or hardwood. If this is your plan, a bare concrete slab won’t be enough because it will look too plain.
The good news is that you have several options you can explore. One is to polish the concrete slab to make it smoother and shinier. Polishing will remove the rough surface of the concrete slab to make it more comfortable for walking. You should also seal the concrete slab flooring to make it resistant to liquid spills.
If you find the idea of having a concrete-looking floor unappealing, you can stain the slab to give it color. This will take the aesthetics of the slab a notch higher. Staining concrete costs between $2 and $4 per square foot, on top of the cost of the actual slab. Visit our Instagram account for design inspirations for your barndominium’s outdoor spaces.
For outdoor concrete slab flooring, you have several options you can explore. Stamping is the process of making the slab look like wood, brick, stone, or tiles. This makes the concrete slab look more attractive. Stamped concrete is an excellent option for the flooring of patios, driveways, and outdoor kitchens. Stamping concrete costs between $9 and $20 per square foot, inclusive of materials.
You can also go for an exposed concrete aggregate. This process involves removing the outermost surface of a concrete slab to expose the aggregates underneath. Common aggregates include pebbles, gravel, and small rocks. Exposed concrete aggregate is suitable for areas that always get wet, like pools, because it is a non-slippery surface. This makes it safer to walk on even when the area is wet.
Tips on How to Save On Concrete Slab Costs
Making a concrete slab can be expensive, so here are some tips to reduce costs.
Mix your own concrete
Ordering wet concrete can be expensive, and you can save money by mixing your own concrete. It can cost you more if the site is hard to reach because some suppliers have fuel surcharges of between $40 and $50 per truckload when delivering to locations beyond their usual delivery area.
Canvass suppliers
Get quotes from several suppliers before deciding. This will allow you to compare prices to get the best deal possible. If you think local suppliers’ prices are too steep, don’t be afraid to look into suppliers from another county. Just be clear about delivery rates so you can see if you are saving money or if it will be more cost-effective to just order locally.
Recycle
If replacing an old concrete slab, you can recycle it to save money. You can crush old concrete and screen it to remove dirt and particles. This will leave you with large and small aggregates to create a new concrete slab. You can also use crushed concrete as fill to level the site.
Final Thoughts
Knowing how to compute the cost of a concrete slab is a valuable skill. It will help you prepare a proper budget for your project. It can also help you scrutinize quotes from prospective contractors. Remember to follow our Facebook page for other articles about barndominiums, pole barn homes, and shouses.
Frequently Asked Questions
What is the price of a concrete slab?
The price of making a concrete slab depends on its size, thickness, and additional features. You can use the cost estimates we presented above as a guide to approximate the cost of your concrete slab. If the size of your slab is irregular, you can use the formula we outlined to compute costs.
Where to buy a concrete slab?
Check your local construction supply companies if you plan on using pre-cast concrete slabs. There are also suppliers online if you cannot find a local one.
Is it cheaper to lay concrete or pavers?
Pouring concrete is cheaper than installing pavers. However, one advantage of laying pavers is that they are easier to repair if a paver gets damaged.
