QA

Quick Answer: How To Lay A Concrete Slab

What do you put under a concrete slab?

You do need gravel under a concrete slab, footing, or patio. Gravel provides a solid foundation for your concrete as it can be compacted. It also improves drainage, preventing water from pooling beneath the concrete.

Can you pour concrete over dirt?

Long story short, yes you can pour concrete over dirt.

Should I put sand under concrete slab?

Pour concrete over a solid, well-drained base Because concrete slabs “float” on the soil, soft ground or voids underneath may cause unsupported areas to crack under heavy weight like vehicles. Pack about 4 in. of sand or gravel over clay and other poorly draining soils to provide even support.

Is it cheaper to pour your own concrete?

Whether you’re pouring concrete countertops or a patio out back, it may be cheaper to pour concrete yourself rather than hiring someone. Whether you’ll save much in doing so depends largely on the amount of concrete needed and the amount of time you have to invest in your concrete project.

How much concrete do you need for a 10×10 slab?

Regarding this, “how much concrete do i need for a 10×10 slab?”, generally you will need 1.23 cubic yards of premixed concrete for a 10×10 slab at 4 inches thick, at 5 inches thick you will need 1.54 cubic yards of concrete and at 6 inches thick – 1.85 cubic yards of concrete.

What’s the best base for concrete?

What is the Best Base for a Concrete Slab? Most people build a driveway or a patio so in that case, a good choice would be a mix of coarse and fine aggregate which will create a compactable base. Overall, a mix of crushed stone and stone dust is the best base material for any concrete flatwork.

How thick should a concrete slab be?

Standard concrete floor slab thickness in residential construction is 4 inches. Five to six inches is recommended if the concrete will receive occasional heavy loads, such as motor homes or garbage trucks. To prepare the base, cut the ground level to the proper depth to allow for the slab thickness.

Is sand a good base for concrete?

Simply put, sand isn’t sturdy enough to work well as a subbase for something like a driveway. It is also difficult to maintain a level sand surface when pouring concrete, and therefore difficult to maintain a uniform thickness of the concrete slab.

Does a 4 inch slab need rebar?

Rebar is not necessary for every concrete project. The general rule of thumb is that if you are pouring concrete that is more than 5 inches in depth, you are probably going to want to add in some rebar to help reinforce the entire structure.

How many bags of cement do I need for 12×12?

To determine how many bags of concrete you will need, divide the total cubic yards needed by the yields, at 4 inch thick, for a 12×12 slab you will need 1.76 yards of concrete, so number of 80lb bag of concrete = 1.76 ÷ 0.022 = 80 bags, No. of 60lb bag = 1.76 ÷ 0.017 = 104 bags & No.

Is sand or gravel better for concrete?

The Importance of Gravel and Sand in Concrete More volume means less air and a stronger product. The size of the gravel also helps to determine the concrete’s strength. Though larger pieces of gravel produce more friction and make it harder to mix, they also make a stronger concrete.

Will concrete crack without rebar?

Without rebar reinforcement, concrete is highly prone to cracks due to tension forces. Rebar helps prevent cracks from growing wider largely by preventing cracked slabs from moving apart.

Can you lay concrete over gravel?

Laying a concrete driveway over an existing gravel one is possible, but it is not generally recommended. However, if the gravel in your driveway is small enough, it is possible to create a cement driveway over the existing one.

How much does it cost to pour a 24×24 slab of concrete?

A typical 24×24 garage slab costs between $3,057 and $5,944 with prices ranging from $5.31 to $8.31 per square foot for a 4” reinforced slab of concrete, and $6.83 to $10.32 per square foot for a 6” slab of reinforced concrete.

How many 80lb bags of concrete make a yard?

One 80lbs bag of Quikrete Concrete Mix will yield approximately . 60 cu ft. So it will take 45 bag to equal one cubic yard of concrete.

How much does a 30×50 concrete slab cost?

The base cost of material for a 30×50 concrete slab is between $2.83 and $5.47 per square foot. The total cost may range from $4,245 to $8,205. However, hiring a contractor may cost between $6 and $8 per square foot, bringing the price range to $9,000 to $12,000. The biggest cost is the material.

How many square feet is a yard of concrete 6 inches thick?

One Cubic Yard of Concrete: 4-inches thick – covers 81 square feet. 5-inches thick – covers 65 square feet. 6-inches thick – covers 54 square feet.

How much area can one bag of cement cover?

How many square feet will a 60 lb bag of concrete do? @ 2″ thick a 60 lb bag of concrete will fill 2.7 sq. ft. @ 4″ thick a 60 lb bag of concrete will fill 1.35 sq.

How much does it cost to pour a 10×12 concrete slab?

Cost of concrete per square foot Slab Size Square Feet Average Cost 10×10 100 $600 10×12 120 $720 10×20 200 $1,200 12×12 144 $864.

How thick should a concrete base be for a garage?

So what constitutes a good garage base? The base itself should be 4″ thick in the main and 8″ thick around the outer edges. Underneath the concrete there should be a minimum 4″ of compacted hardcore. The edges of the base should be troweled off or chamferred to allow any water to drain off.

Is it hard to pour concrete?

On a small scale, concrete is fairly easy to work with, but installing an entire patio can be a challenge. It is possible to build an attractive concrete patio yourself, but careful planning and preparation is necessary. Once concrete is in place, you’re stuck with it forever; replacement is costly and difficult.

Can I use gravel as a sub base?

If your builder uses the gravel he may find it will dissipate too easily into the ground and will spend more time and money to get the levels needed. I would not advise using the gravel. A well constructed base means your drive will never get sink holes.