Menu Close

how much does concrete weigh banner pic

How Much Does Concrete Weigh?

Concrete is one of the most versatile building materials in the world. It’s very strong, durable and easy to work with. And it’s simple to make. Concrete is a mix of sand, cement and stone aggregate mixed together. When you add water it hardens and then cures for around 28 days to achieve it’s full strength. The strength of concrete is measured in pounds per square inch or psi. When you look at a Quikrete premixed concrete bag and it says 3500, that’s the strength of the concrete, 3500 psi. Quikrete concrete bags come in a variety of weights ranging from 40 lbs all the way up the the standard 80 lb bag. When mixed with water they get even heavier because of the weight of the water. So how much does concrete weigh when it’s mixed and poured?

A solid slab of concrete’s average weight is 4,050 pounds (2 tons) per cubic yard or 150 pounds per cubic foot. The actual weight per yard can vary based on the ingredients and ratios used to make the dry mix and the amount of water used to mix it. Stronger concrete is heavier because it has more stone than cement.

Concrete’s weight is based on volume which is a simply calculation to make. Multiple the length x the width x the depth of a slab and you’ll get the volume. Another way to look at it is square footage x depth.

Broken concrete weighs closer to 2,025 pounds (1 ton) per cubic yard, or 75 pounds per cubic foot. When you breakup concrete and load it in a dumpster, there will be lots of open space between the chunks. That’s why broken concrete weights so much less per yard then wet or poured concrete.

Why Does Concrete Weigh So Much?

Concrete is made up of just a few ingredients, sand, cement and aggregate stone mixed with water. These 4 things are what makes concrete so heavy.

Unlike other natural building materials like real stone or wood, concrete doesn’t come from nature in it’s usable form. It’s made from natural material, but it’s also man made. The materials are mixed together in a specific ratio with water to make them hard and strong. The weight of concrete is ultimately the weight of all these materials mixed together. For this reason, concrete doesn’t have a set weight per cubic yard. Ingredients used and their ratios can vary a bit from batch to batch which changes the weight or your concrete.

Some concrete mixes use more stone which makes it denser and stronger while others are lighter and more porous. Some concrete is mixed with heavy, dense aggregate while other batches are made with fine sand and small round stones.

These factors, and things like additives, will change how much your concrete ultimately weighs when mixed. One of the great things about using Quikrete premixed concrete is that the weight is set by bag so there aren’t as many variables. Concrete weight per yard only varies if you make your own batch or buy it by the truck load.

How Much Do Concrete’s Ingredients Weigh?

The weight of concrete is equal to the weight of all it’s ingredients plus water. Below is a list of those ingredients and their average weight.

  • Portland Cement. 12.5 pounds per gallon
  • Aggregate. 10-15 pounds per gallon
  • Sand. 12.5 pounds per gallon
  • Water. 8.3 pounds per gallon

This is not an estimate of how much dry concrete weighs because you don’t add an equal amount of each material. Concrete mixes all use the same basic ingredients, but the ratios change. More aggregate makes a stronger concrete that’s harder to smooth out and work with. It’s better for foundations and footings. Lighter concrete uses less aggregate with more cement. This type of mix is better for smooth surfaces that don’t need a high psi like countertops.

If we were to estimate the weight of concrete components for a standard 3500 psi cubic yard of concrete, it would look like this:

  • Portland Cement. 6 bags per cubic yard (567 pounds; 96 pounds each)
  • Aggregate. 2 tons per cubic yard (3,500 pounds)
  • Sand- 1.5 tons per cubic yard (2,800 pounds)
  • Water- 40 gallons per cubic yard (320 pounds)

Altogether, this 3500 psi mix of concrete would weigh around 7,180 pounds per cubic yard when poured. Once concrete cures it dries out. This doesn’t change it’s weight that much since most of the weight comes from the aggregates and cement.

Things That Effect Concrete’s Weight

There are a few other things that effect the final weight of a concrete structure.

  • Additives. Concrete reinforcement is a common additive. Things like fiber or micro rebar. While they don;t add a ton of weight they do effect the total.
  • Wire Mesh. Many slabs include a layer of wire mesh in the middle as reinforcement.
  • Rebar. The biggest addition to the weight of concrete is rebar. Almost all structural concrete footings, walls and foundations have rebar inside. The size of steel rebar varies based on what’s being built but it’s all heavy. A rebar cage can easily add a half ton or more to a wall of concrete.

Why Concrete’s Weight Matters

For most projects the weight of your concrete doesn’t really matter. But in some cases it does. Below we’ll tell you how to calculate the weight and give you a few examples of why it matters.

The weight of concrete is calculated using the length, width, and height of your structure. From these measurements you can calculate the structure’s volume and then it’s weight. The easiest way for me to do it is by Quikrete bag. An 80lb bag provides about .6 cubic feet of concrete. A cubic yard of concrete is 27 cubic feet. By understand the volume of what your building you can easily figure out how many bags it takes to fill that volume and then simply multiple that number by 80 lbs.

Why We Weigh Concrete

  • If your building concrete countertops it’s important to understand how much concrete weights because the cabinets have to support the weight. Depending on how thick your countertops are, concrete can weigh more than stone. If you throw in a farmhouse sink the weight your countertops need to support can add up fast and may need reinforcement.
  • If your using the concrete as an anchor, like when you pour fence posts, it’s good to know how much weight is holding down the posts.
  • Interior concrete floors are getting more and more popular each year. Especially in Modern style homes. You need to calculate the weight of the slabs carefully because the framing has to support it.
  • How much concrete weighs is very important if your making a cast item like a fireplace surround, mantle, planter or furniture. Eventually you’ll have to move that stuff around and support it.
  • When doing demo work we have to carefully calculate the weight of the concrete or else we risk overloading the dumpsters. Most concrete dumpsters have a 20,000 pound limit which you can’t go over. This is due to safety regulations and the truck’s limitations.
  • How much concrete weighs and how strong it is are related. A 4″ thick slab won’t be as strong as an 8″ and it’ll weight half as much. Also, the higher the psi rating of concrete the heavier it is. Because of these two factors, the stronger the concrete, the thicker, denser and heavier it will most likely be. Although you can overcome some of this with additives like fiber, rebar or wire mesh.

Summary: How Much Does Concrete Weigh?

Concrete is one of the most versatile building materials in the world. It’s very strong, durable and easy to work with. And it’s simple to make. Concrete is a mix of sand, cement and stone aggregate mixed together. When you add water it hardens and then cures for around 28 days to achieve it’s full strength. The strength of concrete is measured in pounds per square inch or psi. When you look at a Quikrete premixed concrete bag and it says 3500, that’s the strength of the concrete, 3500 psi. Quikrete concrete bags come in a variety of weights ranging from 40 lbs all the way up the the standard 80 lb bag. When mixed with water they get even heavier because of the weight of the water. So how much does concrete weight when it’s mixed and poured?

A solid slab of concrete’s average weight is 4,050 pounds (2 tons) per cubic yard or 150 pounds per cubic foot. The actual weight per yard can vary based on the ingredients and ratios used to make the dry mix and the amount of water used to mix it. Stronger concrete is heavier because it has more stone than cement.

Concrete’s weight is based on volume which is a simply calculation to make. Multiple the length x the width x the depth of a slab and you’ll get the volume. Another way to look at it is square footage x depth.

Broken concrete weighs closer to 2,025 pounds (1 ton) per cubic yard, or 75 pounds per cubic foot. When you breakup concrete and load it in a dumpster, there will be lots of open space between the chunks.

If you have any questions or comments e-mail us any time. We’d love to hear from you.

Related Posts

SUBSCRIBE

Get Notified About New Articles, GREAT DEALS on Home Goods, Videos & Product Reviews.

We Update Weekly & It’s All Completely FREE.