Formulas for Calculating Amounts of Materials Needed
In this post I will explain how to calculate Square Footage, Square Yardage, and Cubic Yardage, which will be of assistance when purchasing certain materials.
1. Square Footage
Square Footage formula is simply: Footage Length x Footage Width = Square Footage.
This Square Footage measurement will be needed for a variety of projects, such as: flooring, sod, painting, paver patios, etc. Since many of the individual items needed in order to complete these types of projects are measured in inches, most suppliers will calculate the Square Footage coverage for you, in order to make it easier for you to purchase the correct amount of the materials needed.
For instance, most flooring comes in boxes, with the amount of Square Footage coverage per box, listed on the outside of the box. Also, most suppliers will be able to tell you, or have posted, the number of pavers needed per Square Foot.
However, if you need to make these calculations yourself, and if your initial measurements, such as a single paver for a patio is in inches, you will first need to calculate the Square Inches of the paver, and then convert that total to Square Feet.
First, you need to know that there are 144 Square Inches in a Square Foot. (12” x 12” = 144“).
Next, you need to know the Total Square Footage of your proposed patio. Length x Width = Total Square Feet.
So, you would make the calculation as follows:
- L x W of a single paver = Square Inches.
- Then, convert the Square Inches into Square Feet, by dividing 144 (# of Square Inches in a Square Foot) by the Total Square Inches of the single paver or patio stone.
- Multiply L x W of your proposed patio = Total Square Feet.
- Total Square Feet for patio x the number of pavers per Square Foot = Total number of pavers needed.
Example: If your paver is 4” x 8”, and your patio will be 20’ x 30’ calculate as follows:
- Multiply 4” x 8” = 32 Square Inches.
- 144” divided by 32” = 4.5 pavers per Square Foot.
- Your 20’ x 30’ patio = 600 Square Feet.
- 600 Total Square Feet x 4.5 pavers needed per Square Foot = 2700 pavers needed.
2. Square Yardage
Square Yardage formula is simply: Square Footage divided by (9) = Square Yardage.
Sod usually comes in (1) Square Yard rolls which measure 6’ Long x 18” Wide.
To verify that this is indeed (1) Square Yard:
- You must first convert all of your dimensions to the same unit of measurement.
- Convert your 18” Width measurement to Feet (18” divided by 12” in a Foot = 1.5 Feet).
- Then, multiply L x W in order to get your Square Footage (6’ Long x 1.5’ Wide = 9 Square Feet).
- Then, divide your Square Footage by (9) to get your Square Yardage.
- (9) Square Feet divided by 9 = 1 Square Yard.
To determine how many rolls of sod will be needed to cover a given area, the formula is simply:
Footage Length x Footage Width = Square Footage.
Square Footage divided by (9) = Square Yardage (or the number of sod rolls needed).
Example: If the area that you need to cover with sod is: 10’ Long x 10’ Wide:
- Multiply the (2) dimensions to get your Square Footage (10’ x 10’ = 100’ Square Feet).
- Divide your Square Footage by (9) to get the number of Square Yards (sod rolls needed).
(100 Square Feet divided by (9) = 11.11 or (12) Sod Rolls needed).
3. Cubic Yardage
Cubic Yardage is measured in yards rather than feet: 3 Feet = 1 Yard.
Cubic Yardage formula is simply: Yardage Length x Yardage Width x Yardage Height (or Depth) = Cubic Yardage.
There are (27) Cubic Feet in (1) Cubic Yard (3’ x 3’ x 3’ = 27).
Cubic Yardage is often used to calculate the amount of material needed for certain yard projects, such as: topsoil, gravel, mulch, decorative stone, concrete, etc. You usually make your initial measurements in feet, multiply L x W x H = Cubic Feet. Then, divide the Cubic Feet by (27), which is the number of Cubic Feet in a Cubic Yard.
Example: If the area you are going to install a given material measures 130’ in Length, is 2’ Wide, and the material to be installed needs to be 12” in Height, the steps to make the calculation is as follows:
- You must first convert all three dimensions to the same unit of measurement. So, convert your 12” Height measurement to Feet (12” divided by 12” in a Foot = 1 Foot).
- Multiply the three dimensions together to find the number of Cubic Feet.
Multiply the L x W x H (130’ x 2’ x 1’ = 260’).
- Divide the number of Cubic Feet by the number of Cubic Feet in a Cubic Yard (27) to find the number of Cubic Yards. (260 divided by 27 = 9.6 Cubic Yards).
You will need 10 Cubic Yards of the material to complete your project.
I hope this helps you in all of your material calculations.
Please take the time to leave a Comment, letting me know how your project went.