A concrete footing is an important structure in every construction project because the burden of the entire building structure depends on it. So, whenever you are starting a new project or laying the foundation, get help from the concrete footing calculator to find the volume of concrete needed for building it.
What is a concrete footer calculator, and how to use it? Let’s tell you everything in detail on this topic!
Understanding Concrete Footing
A concrete footing is a strong, widened base of the building’s foundation. It is a major part of the construction process and a starting point that distributes the weight of the building structure evenly to the ground.
A concrete footing is placed below the foundation, walls, and columns. It is made of concrete and also reinforced with steel bars that are placed in a dug-out trench to support the foundation of the building. Concrete footing makes the building stand strong, and thus it should be constructed with care and proper calculations.
Concrete Footing Calculations
So, now you know what a concrete footing is, let us also tell you what a concrete footer calculator is.
As its name says, it is a simple calculating tool that is used to calculate the amount of concrete needed for laying the base of the building.
It works with a built-in formula that calculates the concrete volume, its cost for the user when they enter the dimensions in it.
Working of a Concrete Calculator
A footing to fill with concrete requires three dimensions.
- Length
- Width
- Height
You have to measure these three areas and find out how many they measure in feet, meters, or any other suitable measurement unit. Now the calculator requires these three dimensions from you to calculate the concrete volume for your footing.
- The length is the longer side of the footing. Check how long the trench is from the walls and measure it. The measurement between the trench and the wall will be the length. Measure the full run to the wall.
- Width shows how much in width the trench footing is dug. This is the shorter side of the footing.
- Height shows the depth of the footing dug in the ground. It shows how deep it is going into the ground. In some calculators, it is also mentioned as “thickness”.
Your next step includes entering these dimensions in the concrete square foot calculator to find out the result. When you enter the details and click on the calculate button, it will start processing and will give you the answer in just a moment.
Square, Strip, Single Isolated Footing & Round Footing
Now, here, let us tell you one most important thing. When you are using a calculator, you have to provide dimensions accordingly. Footings are of many types, including raft, pile, combined, strip footing, etc, but in terms of calculations, these three terms are mostly used.
A square footing has equal length and width and is used for square bases. It is placed under square or rectangular columns. Its length is measured as one side of the square base.
To take its measurements, you have to follow this,
- Length is one side of the square base
- Width is another side of the square base. It is the same dimension
- Height – the depth of the base
To calculate this, you have to use a concrete square foot calculator to get the volume correctly.
On the other hand, a strip footing is a continuous footing that runs along the wall and connects multiple columns. Its measurements are different from square footing because of its length and width. It is much wider than the wall it supports.
- Its length is the full run to the wall.
- Its width is the trench width.
- Height is the depth that shows how deeply it is dug into the ground.
However, in the case of single footing, which is also known as pads, the length is taken as the distance along one side of the wall. It is known as a single footing because it is an isolated footing that supports only one column. Now, here, you must also know that this can be of any shape.
- Its length will be one side of the pad
- Width will be the other side of the pad
- Height is its thickness.
Now, when we come to the round footing, here everything turns. Round footing is used under the tanks, round bases, or posts. It has a circular look, and its dimensions cannot be measured as length, width, or height. For this, the measurements are different because the shape is symmetrical. It requires two dimensions: the diameter of the circle and the depth.
The diameter is the radius of the circle. The formula used to calculate the volume for such a footing is the “area of the circle”.
- Its diameter will be the passing line from one side of the circle to another
- Its depth will be the thickness.
Understanding Units for Using the Calculator
Units play an important role in overall calculations. The footing calculator features many units, which should be chosen wisely as per the measurement taken. If you mix them up, your result will be completely wrong.
The given units in the calculator are meters, centimeters, inches, feet, and yards. These are the units for length, width, and depth. You have to select them carefully. If your depth is in inches, select inches from the given list of units.
The main benefits for using the calculator is that you don’t have to convert the unit manually, from inches to feet or other units. You can measure in any of the units and add the value according to your measurements.
Moreover, you must also know that concrete is measured and sold in three main units, which are cubic feet, cubic yards, and cubic meters. Our concrete calculator gives you the volume of concrete in all these three units, and in the case of crushed concrete, you will get the volume in tons because crushed concrete is measured in tons.
Fortunately, online calculators are also known for helping you know the number of premixed concrete bags you will need for your project. It will show the result explaining the quantity of bags like 50 lb bags, 80 lb bags, 90 lb bags, and in some calculators, it is in pounds or kgs.
Here is a short table to help you understand these units further:
| Units | Conversions |
|---|---|
| 12 inches (in) is | 1 foot (ft) |
| 27 cubic feet (ft³) is | 1 cubic yards (yd³) |
| 1 cubic yards (yd³) | 1.5 tons |
| 1 cubic meter (m³) | 35.31 cubic feet (ft³) |
| An 80 lb premixed concrete bag contains | 27 cubic feet (ft³) |
| 1 cubic yard of concrete | 45 (80 lb) concrete bags |
Mistakes People Make While Calculating Footing Concrete
Using a calculator is easy, but people usually make silly mistakes that give them the wrong answer. We are highlighting some mistakes here, so you can avoid them when you are using the footing calculator.
Using Different Units for Every Dimension
Although the calculator gives you the ease of selecting any unit from the given range, one thing you should always keep in mind is to use a single unit for every dimension.
For instance, you have entered the length in feet, width in meters, and depth in inches, and you are calculating the volume of concrete. The result will be a mess.
Want to know why? The answer is short and easily understandable.
A calculator is just a gadget that relies on the information we provide. So when you enter three different dimensions with three different units, it will get puzzled and might give you the wrong answer. So, always select one unit for all the measurements. Similarly, if you are calculating manually, first convert the dimensions into one unit, then do the calculation.
For converting, there is a simple tip, and that is you have to divide or multiply the number based on your conversion. For example, if you want to convert inches into feet, divide the number by 12, and if you want to convert from feet to inches, multiply by 12, because 1 foot is 12 inches.
Unit Conversion or Calculator Entry Errors
Suppose the calculator is asking for the radius and you are entering the diameter. This is a big mistake. Radius and diameter are two different things. If your calculator is asking for the radius, convert your diameter to radius and then enter for calculation, or simply move to a calculator that asks for diameter. You can convert the diameter intoa radius by dividing the number by 2.
Just remember this formula:
Radius = Diameter ÷ 2.
Using the Wrong Shape Calculator to Calculate
Every footing is different and is calculated in a different shape calculator. The concrete square foot calculator is for a square footing only. If you try to calculate a T-shaped footing with a square footing calculator, the calculation will be off. A T-shaped footing is used in basements and is a totally different type. It has stem areas, flange areas, and the calculator for calculating this is not the same.
Measuring Wrong Way
Using the wall’s full run for a pad footing or using a single pad size when you need the full run is a major measurement mistake that can totally underestimate your result. One mistake is not measuring the depth on uneven bottoms. A slope or stepped trench bottom has different depths along the run.
So, these are some common mistakes people make while using the calculator, and then claim that the calculator gives the wrong result.
Why Should You Use a Concrete Calculator Instead of Relying on Contractors?
A Concrete footer calculator gives you a more accurate estimate than the contractors. They just rely on the rough estimate they make following their experience in the field. A calculator gives you a correct estimate of the concrete volume you will need for the project.
Moreover, a calculator saves you time and money. When you are relying on a calculator, you don’t have to hire a contractor for an estimation idea. You can get the estimate yourself and contact the contractor for their services and labor.
So, this is all about the concrete footing calculator. It is simple to use and gives you an accurate, concrete estimate. All you have to do is understand how to use it. Select the right shape and enter the correct dimensions.
Looking for a reliable tool to get a Concrete volume estimate for your project? Check our Concrete Calculators and plan your project budget now!
Frequently Asked Questions
What is the purpose of a concrete footing calculator?
The purpose of the footing calculator is to give you an estimate of the volume of concrete you need to lay a footing. Its result depends on the data you provide. The data is in the form of dimensions of the footing you prefer to build.
How to take the dimensions of the footing if it is T-shaped, not square or rectangular?
To take the dimensions of T-shaped or irregular-shaped footing, first break them into smaller parts. It means dividing the area into different parts, some into squares, some rectangles, or circles as per your ease. Then calculate each separately using a calculator. After this, add their volume together to understand how much you need.
Is the concrete footing calculator result 100% accurate?
Yes, the concrete footing calculator result is accurate based on your dimensions. If you have provided the right dimensions and selected the right units, the result will be correct. If you are looking forward to buying concrete on the given estimate, then we recommend that you give a round of nearly 10%, which means adding 10% extra to your purchase.
Do I need construction experience to use the concrete footing calculator?
No, anyone can use this calculator. You do not need construction experience, but you should know how to take the dimensions correctly. If you have the knowledge of taking measurements correctly, then it is simple for you to use. Its answer totally depends on your dimensions, as it works with the dimensions you provide.