So, how many 60lb bags are in a yard of concrete? A typical 60lb bag of concrete mix makes about 0.5 cubic feet of concrete once mixed with water. A full yard of concrete is 27 cubic feet. Doing the math, that means you need around 54 bags of this size to get one cubic yard. Keep in mind, this number can change a little based on the exact mix in the bag and how much water you add. This guide will help you figure out just how much concrete you need and how many bags to buy for your project.
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Fathoming the Basic Numbers
Before you start pouring concrete, you need to know some basic numbers. This helps you buy the right amount. We will look at what a cubic yard is and how much concrete comes from one bag.
What is a Cubic Yard?
Think of a cubic yard like a box. This box is 3 feet long, 3 feet wide, and 3 feet tall. If you fill this box with concrete, that is one cubic yard of concrete.
Why do we talk about cubic yards? Because concrete for big jobs, like driveways or patios, is often ordered and measured in cubic yards. When you buy concrete in bags, you need to figure out how many bags add up to the cubic yard amount you need.
One cubic yard is the same as 27 cubic feet. This is easy to remember: 3 feet x 3 feet x 3 feet = 27 cubic feet. We use cubic feet when working with bags because bag yields are usually given in cubic feet.
Grasping Concrete Bag Yield
Every bag of concrete mix gives you a certain amount of mixed concrete. This is called the yield. The yield tells you how much concrete volume you get from one bag after you add water and mix it up.
For a 60lb bag of concrete mix, the yield is usually about 0.5 cubic feet. This means one 60lb bag makes roughly half of a cubic foot of mixed concrete. This is a key number when you calculate concrete bags needed for your job. It shows you the concrete yield per 60lb bag. Knowing how much concrete does a 60lb bag make in cubic feet is the first step to figuring out bags per yard.
It is important to know that this yield number is an average. The exact amount can change slightly. Things like how much water you add or the type of mix can affect the final volume. But 0.5 cubic feet per 60lb bag is a good number to use for planning. This is how many cubic feet in a 60 lb bag of concrete you can expect.
Calculating How Many Bags You Need
Now that you know the basic numbers, let’s figure out how many bags make a yard. We will use the yield of one bag and the total volume in a yard.
Simple Math: Yard to Bags
A cubic yard is 27 cubic feet.
A typical 60lb bag yields about 0.5 cubic feet.
To find out how many bags you need for one cubic yard, you divide the total volume you need (in cubic feet) by the volume you get from one bag (in cubic feet):
Number of bags = Total Volume Needed (in cubic feet) / Yield Per Bag (in cubic feet)
For one cubic yard:
Number of 60lb bags = 27 cubic feet / 0.5 cubic feet per bag
Number of 60lb bags = 54 bags
So, the simple math says you need about 54 bags of 60lb concrete mix for one cubic yard. This helps you calculate concrete bags needed for a 1-yard job.
Why the Number Changes
We said you need around 54 bags. Why “around”? Because the exact number can change a little. Here are some reasons why:
- Water Amount: Adding a bit more or less water than the bag suggests can change the final volume slightly. Too much water also makes the concrete weaker. Always follow the water amount on the bag for the best strength.
- Mixing: How well you mix the concrete can affect the yield.
- Type of Mix: Different brands or types of concrete mix might have slightly different yields listed on the bag. Always check the bag label!
- Waste: You almost always have some waste. This could be from spills, uneven ground, or over-excavating your area. We will talk more about this later.
- Air Content: The amount of tiny air bubbles in the mix (can be put there on purpose for freeze-thaw resistance) affects the final volume.
Because of these things, 54 bags per yard is a good starting point. But it is smart to plan for a little extra.
Figuring Out Your Project Volume
Okay, you know a yard is 27 cubic feet and a 60lb bag makes about 0.5 cubic feet. But how do you know how many cubic feet (or cubic yards) your project needs? This part is about concrete volume calculation and estimating concrete needed.
Measuring Your Space
Most concrete projects are based on a simple shape, like a square or a rectangle. To find the volume of concrete you need, you measure the length, width, and depth of the area you want to fill.
- Length: How long is the area?
- Width: How wide is the area?
- Depth (or Thickness): How deep or thick do you want the concrete?
Measure these in feet or inches. It is often easier to measure in inches and then convert to feet.
Let’s say you want to pour a small slab for an air conditioner unit. You measure:
* Length = 4 feet
* Width = 3 feet
* Depth = 4 inches
Converting Units
Volume math is easiest when all your measurements are in the same unit, like feet. You need to convert inches to feet.
There are 12 inches in 1 foot.
To convert inches to feet, divide the number of inches by 12.
In our example:
Depth = 4 inches
Depth in feet = 4 inches / 12 inches per foot
Depth in feet = 0.333… feet (or 1/3 foot)
So, your measurements in feet are:
* Length = 4 feet
* Width = 3 feet
* Depth = 0.333 feet (1/3 foot)
Volume in Cubic Feet
Now, multiply your three measurements together (Length x Width x Depth) to get the volume in cubic feet.
Volume = Length (ft) x Width (ft) x Depth (ft)
In our example:
Volume = 4 feet x 3 feet x 0.333 feet
Volume = 12 cubic feet x 0.333 feet
Volume = 4 cubic feet
So, your small slab needs 4 cubic feet of concrete.
Volume in Cubic Yards
If you want to know your volume in cubic yards, you take the volume in cubic feet and divide it by 27 (because there are 27 cubic feet in a cubic yard).
Volume in Cubic Yards = Volume in Cubic Feet / 27
In our example:
Volume in Cubic Yards = 4 cubic feet / 27 cubic feet per yard
Volume in Cubic Yards = 0.148 cubic yards (about 0.15 cubic yards)
This number tells you how much of a full yard you need. Most small projects using bags will be less than a full cubic yard. For bigger jobs, you might calculate in cubic yards first. Many online tools act as a simple cubic yard concrete calculator – you just put in your measurements, and it tells you the volume.
Once you have your volume in cubic feet (4 cubic feet in our example), you can easily figure out how many 60lb bags you need.
Number of 60lb bags = Total Volume Needed (in cubic feet) / Yield Per Bag (in cubic feet)
Number of 60lb bags = 4 cubic feet / 0.5 cubic feet per bag
Number of 60lb bags = 8 bags
So, for a 4 ft by 3 ft slab that is 4 inches thick, you would need about 8 bags of 60lb concrete mix. This process shows you how to calculate concrete bags needed for your specific project.
Looking at Different Bag Sizes
Concrete mix comes in different bag sizes, not just 60lb. The most common sizes are 40lb, 60lb, and 80lb. The yield changes with the bag size.
Common Bag Weights
- 40lb Bags: These are lighter and easier to carry. They make the least amount of concrete per bag.
- 60lb Bags: These are a good middle ground. This is the size we have been focusing on.
- 80lb Bags: These are heavier but give you the most concrete per bag.
Comparing Yields
Each bag size has a typical yield in cubic feet:
- 40lb Bag: Usually yields about 0.3 cubic feet of concrete.
- 60lb Bag: Usually yields about 0.5 cubic feet of concrete.
- 80lb Bag: Usually yields about 0.6 cubic feet of concrete.
Knowing these yields lets you choose which bag size is best for your job. If you only need a small amount of concrete, 40lb bags might be fine. If you have a larger job but still want to use bags, 80lb bags mean fewer bags to mix.
Let’s see how many of each bag size you would need for one cubic yard (27 cubic feet):
- 40lb Bags: 27 cubic feet / 0.3 cubic feet per bag = 90 bags
- 60lb Bags: 27 cubic feet / 0.5 cubic feet per bag = 54 bags (as we calculated before)
- 80lb Bags: 27 cubic feet / 0.6 cubic feet per bag = 45 bags
Concrete Mix Yield Chart
This table shows the typical yield for common bag sizes and how many of each you would need for one cubic yard. Remember, these are average numbers. Always check the bag!
| Bag Size | Approximate Yield (Cubic Feet) | Approximate Bags Per Cubic Yard (27 cu ft) |
|---|---|---|
| 40 lb | 0.3 | 90 |
| 60 lb | 0.5 | 54 |
| 80 lb | 0.6 | 45 |
This chart is a quick guide to concrete yield per 60lb bag and other sizes. It is helpful for estimating concrete needed based on the bag size you choose. It also gives you an idea of concrete bag coverage based on volume.
Planning and Buying Your Concrete Bags
You have measured your project, figured out the volume, and calculated how many bags you need based on the yield. Now it is time to plan your purchase.
The Importance of Extra
A very common mistake people make is buying exactly the number of bags they calculated. This is risky! Things happen:
- Your measurements might be slightly off.
- The ground you are pouring into might be a little uneven or deeper than you thought in spots.
- You might spill some mix or mixed concrete.
- The actual yield from the bag might be slightly less than the average.
Because of this, it is always smart to buy a little extra concrete mix. A good rule of thumb is to add 10% to 15% to your calculated number of bags.
Let’s go back to our example of the 4 cubic foot slab that needed 8 bags of 60lb mix.
Calculated bags needed: 8 bags
Add 15% for safety: 8 bags * 0.15 = 1.2 bags
Total bags to buy: 8 + 1.2 = 9.2 bags
Since you cannot buy parts of a bag, you would round up to 10 bags. Buying 10 bags for that small project gives you a good cushion. It is much better to have one bag left over than to run short in the middle of pouring concrete.
For larger projects, the 10-15% extra rule is even more important because small errors over a large area add up to more volume. This is key for accurate estimating concrete needed.
Checking the Bag Label
While the numbers we have given are typical, the exact yield can sometimes vary slightly by brand or product. Always check the label on the concrete mix bag you plan to buy. The label should tell you the approximate yield in cubic feet. Use that number in your calculation instead of the average 0.5 cubic feet if it is different. This gives you the most accurate calculation of concrete bags needed.
The label might also give information about concrete bag coverage at a specific depth. For example, it might say “covers X square feet at 4 inches thick.” You can use this information, too, but calculating based on volume (cubic feet) and yield is often more flexible for different depths.
Concrete Bag Coverage Explained
Let’s look closer at concrete bag coverage using our yield number. If a 60lb bag yields 0.5 cubic feet, how much area does it cover? This depends on how thick you pour the concrete.
Remember, Volume = Area x Depth.
If you know the volume (yield per bag) and the depth you want, you can find the area it covers:
Area = Volume / Depth
Let’s use our 60lb bag yield of 0.5 cubic feet and a depth of 4 inches (which is 1/3 or about 0.333 feet).
Area = 0.5 cubic feet / 0.333 feet
Area = about 1.5 square feet
So, one 60lb bag will cover about 1.5 square feet if you pour it 4 inches thick.
What if you only need it 2 inches thick (about 0.167 feet)?
Area = 0.5 cubic feet / 0.167 feet
Area = about 3 square feet
What if you need it 6 inches thick (0.5 feet)?
Area = 0.5 cubic feet / 0.5 feet
Area = 1 square foot
As you can see, the concrete bag coverage in square feet changes a lot based on the depth. That is why knowing the yield in cubic feet is very useful – you can figure out coverage for any depth.
Working with Bagged Concrete
Once you have your bags, you need to mix and place the concrete.
Mixing Tips
- Read the Bag: Always read the mixing instructions on the bag first.
- Use the Right Amount of Water: Do not guess! Use the amount of water suggested on the bag. Adding too much water makes the concrete weak. It is better to add slightly too little at first and add small amounts until it is the right consistency. The mix should look like thick oatmeal or peanut butter, not a watery soup.
- Mix Thoroughly: Mix until the color is even and there are no dry spots of mix left. You can mix in a wheelbarrow with a hoe for one or two bags, but for more bags, a concrete mixer machine is much easier and gives a better mix.
- Mix Full Bags: For the most consistent results and predictable yield, try to mix full bags at a time.
Placing and Finishing Basics
- Prepare the Area: Make sure the area is ready before you mix. Build forms if needed. Make sure the base is firm and slightly damp (but not muddy or puddled).
- Get Help: Concrete work goes fast once you start. It is very hard to mix and pour by yourself, especially for more than a few bags. Have friends or family help.
- Work Quickly: Once mixed, concrete starts to harden. You need to place it and finish it fairly quickly. Do not mix more than you can use in about 30-60 minutes.
- Compact the Concrete: After pouring, push the concrete into all the corners and along the edges to remove air pockets. You can use a shovel or a piece of wood.
- Smooth the Top: Use a straight board (a “screed”) to level the concrete with your forms. Then, use floats and trowels to smooth the surface.
- Cure the Concrete: This is very important for strength! Keep the concrete damp for at least a few days after pouring. Cover it with plastic, wet burlap, or use a curing compound. This stops the water from drying out too fast.
Avoiding Waste
While buying extra is good, you also want to avoid needless waste.
- Accurate Measurement: Double-check your length, width, and depth measurements.
- Even Base: Prepare a level base for your concrete. Filling low spots with extra concrete is wasteful.
- Careful Mixing: Do not spill mix powder or wet concrete.
- Only Mix What You Need: If you have calculated you need 8 bags and bought 10, and you are on your 8th bag and it looks like it might be just enough, do not automatically mix the 9th bag. See if the 8th bag fills the space. If it does, you save the 9th and 10th bags for another project or return them if possible.
Bags Versus Ready-Mix
For any concrete project, you have two main options: using bags of concrete mix or ordering ready-mix concrete delivered by a truck.
When Bags Make Sense
Bagged concrete is usually better for:
- Small Jobs: Patching, setting a few fence posts, pouring a small step or pad (like the AC unit example).
- Hard to Reach Areas: If a concrete truck cannot get close to your project, bags are the only option.
- Jobs Spread Out Over Time: If you are doing a job in stages over different days, bags allow you to mix just what you need each time.
- DIY Projects: Many homeowners find bags more manageable for small jobs.
When Ready-Mix is Better
Ready-mix concrete from a truck is usually better for:
- Large Jobs: Driveways, large patios, foundations, slabs needing several cubic yards or more.
- When You Need Concrete Fast: A truck can deliver a large amount all at once.
- Consistent Mix: Ready-mix from a plant is usually very consistent in quality and strength.
- Less Labor: You do not have to do the physical work of mixing dozens of bags.
For any project needing one cubic yard or more, you should seriously consider ready-mix concrete. While you could mix 54 or more bags, it is a massive amount of work and hard to get a consistent result across so many batches. The cost difference might also shrink for larger volumes when you factor in your labor and potential for uneven quality with many small bag mixes.
Wrapping Up Your Concrete Plans
So, to recap: A cubic yard of concrete is a volume 3 feet by 3 feet by 3 feet, totaling 27 cubic feet. A standard 60lb bag of concrete mix typically yields about 0.5 cubic feet of mixed concrete. This means you need about 54 bags of 60lb mix to make one cubic yard.
However, the number of bags you need for your project depends on its exact size. You must figure out the volume of your project in cubic feet (Length x Width x Depth, after converting inches to feet). Then, divide your project’s cubic feet volume by the yield of the bag you are using (0.5 cubic feet for a 60lb bag) to find the number of bags needed.
Always, always, add 10% to 15% extra bags to your calculation to account for errors, waste, and unevenness. This extra cost is small compared to the headache of running short. Check the bag label for the exact yield if possible. Know that 40lb bags yield less concrete per bag (~0.3 cu ft) and 80lb bags yield more (~0.6 cu ft).
Bagged concrete is great for small jobs or hard-to-reach spots, but for larger projects needing a yard or more, consider ready-mix concrete for ease and consistency.
With careful measuring, calculation, and planning for a little extra, you can figure out exactly how many 60lb bags (or other sizes) you need for your concrete job and have a successful pour!
Common Questions People Ask
Q: What is the yield of an 80lb bag of concrete mix?
A: A typical 80lb bag of concrete mix yields about 0.6 cubic feet of concrete once mixed. This means you would need around 45 of these bags to make one cubic yard (27 cubic feet / 0.6 cubic feet per bag).
Q: How much water do I add to a 60lb bag of concrete mix?
A: You must follow the instructions on the specific bag you buy. The amount of water needed can vary slightly by brand and mix type. It is usually given as a range (e.g., 5-6 quarts). Start with the lower amount and add more slowly until the concrete reaches the right consistency – it should be workable but not soupy.
Q: Can I mix concrete bags in a wheelbarrow?
A: Yes, you can mix one or maybe two bags of concrete mix at a time in a large wheelbarrow using a sturdy hoe. For more bags, especially multiple bags per batch, a small electric concrete mixer is much more efficient and gives a better, more consistent mix.
Q: Is a cubic yard a lot of concrete?
A: Yes, a cubic yard (27 cubic feet) is a significant amount of concrete for typical home improvement projects. For example, a slab 10 feet by 10 feet that is 4 inches thick needs about 1.25 cubic yards. Mixing this amount from bags (around 68 bags) would be a very large and physically demanding job for a homeowner. This is why ready-mix trucks are often used for jobs this size or larger.