How Many Bags of Concrete Do I Need for a 10x10 Slab?

Bag and Cost Calculations

A 10x10 slab poured at 4 inches thick requires about 1.25 cubic yards of concrete. Since one cubic yard equals roughly 45 80lb bags, you’ll need around 56 bags for the full slab. If you use 60lb bags, you’ll need closer to 74.

The cost depends on bag size and location. At an average of $6 per 80lb bag, the material cost is about $330. If you hire a contractor, labor and finishing can bring the total to $750–$1,000 or more. For larger pours, it may be cheaper to order ready-mix concrete instead of hauling dozens of bags.

Mixing this many bags by hand is labor-intensive. Equipment like a 6 cu ft concrete mixer helps speed up the process, allowing you to blend multiple bags at once and keep the pour consistent.

Reinforcement and Structural Needs

Many DIYers ask if rebar is needed for a 10x10 slab. For small patios or walkways, wire mesh or fiber reinforcement may be enough. Rebar is recommended for heavier loads, such as driveways or shop floors, to help prevent cracking.

Not all slabs require rebar, but reinforcement increases durability. Bagged mixes like Quikrete are just as strong as standard ready-mix when cured properly, reaching 4,000 PSI or more depending on the blend. The key is ensuring proper thickness and curing practices.

Slab Preparation

Proper preparation is essential for slab performance. A compacted gravel base helps with drainage and prevents shifting. Most slabs need 3 to 4 inches of crushed stone as the foundation.

Using a vapor barrier beneath your slab is highly recommended, especially for indoor or moisture-sensitive projects. A heavy-duty moisture barrier prevents ground water from weakening the slab over time.

To prepare the ground, clear vegetation, compact the soil, and lay the gravel base before setting forms. Skipping this step can lead to cracks and uneven settling later on.

Thickness and Design

For patios and walkways, a 4-inch slab is standard. Driveways often need 5 to 6 inches for added strength. Thinner slabs may save material costs but risk early cracking under weight.

Design also matters. Slabs should have slight slopes for water drainage. For pads used under sheds or HVAC units, a standard 4-inch slab is usually enough.

DIY vs. Professional Pouring

Yes, you can pour a 10x10 slab yourself, but it requires planning and labor. You’ll need tools like a mixer, screed, and finishing trowels. If you’re inexperienced, the job may take longer and result in uneven finishes.

Pouring new concrete over old slabs is possible but not always recommended. The old surface must be roughened and bonded properly, or the new layer may crack or separate. In many cases, it’s better to remove old slabs and start fresh.

Cost Comparisons for Larger Slabs

A 12x12 slab costs slightly more—around $500 for DIY and up to $1,200 professionally. Larger slabs like a 50x100 can cost tens of thousands of dollars due to volume, reinforcement, and finishing labor.

At that scale, contractors almost always use ready-mix delivery. For smaller slabs like a 10x10, bagged mixes remain a cost-effective choice, especially when paired with efficient mixing equipment to save time and effort.