Content of the material
 Reader Success Stories
 Video
 What to leave out
 How much to allow for waste?
 How To Measure Square Footage Of A House In 3 Steps
 Square Footage Of A House Example
 How to use the square footage calculator
 How to Calculate the Square Feet of a Home or Residence
 How to Calculate Price per Sq Ft
 How many square feet is a 20×20 room?
 Methods for how to calculate square feet for different shapes
 How to calculate square feet for squares and rectangles
 How to calculate square feet for triangles
 How to calculate square feet for circles
 How to calculate square feet for trapezoids
 How to calculate square feet for rhombuses
 How to calculate square feet for parallelograms
 Measuring for Schluter Profile Edging
Reader Success Stories

Monica Williams Nov 6, 2016
“This article and video showed me how to calculate the square footage of my space. I’m planing to tile my living room (rectangle) and saw at Costco a beautiful tile. The box said it covers almost 10 square feet. Now I will measure my living room and see how many boxes I need. Thank you.” …” more
Video
What to leave out
A good rule of thumb to ensure you’re taking proper measurements is to exclude space you can’t walk on or live in. These types of spaces do not count as “gross living area.”
“Someone might think, ‘If I get the measurement of my first floor and I have a twostory house, I just multiply that by two,’” Day says. However, if that first floor includes a twostory foyer, you can’t count the nonusable space.
Basements and garages, even if they are finished, don’t generally count toward total square footage. Basements are typically excluded because they are built below grade, meaning below ground level. If your state does allow basements to be included in the total square footage of a home, though, you’ll likely need an ingress and egress, or a safe way to enter and exit the basement to the outside.
Finished attic spaces — with some regulations, including ceiling heights — can count toward the total square footage of your home. If you are planning to sell your home, work with a real estate agent to craft a listing that accurately reflects your property.
How much to allow for waste?
To allow for waste, you must consider the installation. For most standard installations, 10% extra for waste is sufficient. Percentage of waste for more elaborate patterns like running tile on a 45 degree angle, herringbone or cross hatch, consult with your installer. Add 15% for tile being installed in a room with lots of jogs and corners. These installations will require more cuts and thus more waste.
Length x Width + Waste = Amount Needed
How To Measure Square Footage Of A House In 3 Steps
To calculate the square feet of a house, you will need to determine each room’s area and add it together. It sounds easy, right? We’re going to try to keep it that way as we walk you through the process. Gather a few tools before getting started:

Tape Measure

Notepad and pen/pencil

Calculator
You may also want someone to assist as you measure, especially in larger rooms. While it all depends on the shape of your house and the complexity of your floor plan, sometimes it’s a good idea to start this endeavor with a helping hand. When you are ready to get started, there are three steps to follow:

Measure the length and width of each room and hallway in your house.

Multiply the length and width of each room separately, which you can write down before your final calculations.

When you are done measuring and multiplying, add the area of each room together.
Square Footage Of A House Example
For example, pretend you live in a ranch home in the shape of a rectangle. The length of the house is 70 feet, and the width is 50. This means to calculate the square footage, you will multiply 70 by 50, resulting in a final calculation of 3,500 square feet. Of course, not every home is a perfect rectangle — making it more timeconsuming to get accurate numbers. That’s why going room by room is often the most practical method. With the proper measurements and some addition, you can still calculate the square footage of your home.
How to use the square footage calculator
Before we get into the nittygritty of how the calculator works and what is the square footage formula, it’s useful to know how to use the calculator, and what each of the components mean. With the “One room/area” option selected, the square footage calculator is composed of the following fields:
 Shape – Select the room/area shape from rectangle, square, circle, triangle, hexagon or octagon
 Measurements – Various measurements of the room, which change depending on the shape selected
 Quantity – Enter the number of rooms/areas that have the same shape and measurements
 Area – Combined square footage of all the spaces as input above
 Unit price – Price (in the local currency) per square foot
 Total cost – Combined monetary value of the spaces described above
To use the calculator is as simple as setting the known values and letting the system calculate the rest. This means that you can use this calculator to compute the price per square foot of a property if you know the total price and total square footage.
If you select the option “Multiple rooms/areas” at the top of the calculate, you can enter the measurements for up to ten rooms or areas and get a grand total at the bottom of the calculator of the square footage. For complex room layouts, divide up the room into simple shapes, such as rectangles, squares, etc., and enter each one as a separate room/area. If you’ve entered a unit price, you’ll also get the total cost.
How to Calculate the Square Feet of a Home or Residence
When measuring the square footage of a home or residence, some special considerations apply to determine the inhabitable square footage. The livable size of a home helps determine the market value and price and helps buyers understand the overall size.
Only livable rooms, with finished walls, floor, and ceiling, count toward the finished area of the home. For a room to be considered livable, the space should be finished and should have heating or air conditioning as applicable.
Indoor spaces count toward the square footage of a home, while outdoor spaces typically do not. In fact, the American National Standards Institute has defined rules^{[1]} for what counts as finished area and which rooms contribute to the gross living area of a home.^{[2]}
To calculate the total area, measure each room in feet using a tape measure. Then, multiply the length and width of each room to get the square footage, then add them all together.
The calculator above can help determine the square feet of each room, then simply add all the room’s areas together. We also have great resources on how to measure rooms and complex spaces.
How to Calculate Price per Sq Ft
To calculate the price per square foot of your home, divide the total price by the number of square feet.
price per ft^{2} = total price ÷ total ft^{2}
For example, to find the price per ft^{2} of a home that costs $200,000 and is 2,000 ft^{2} use this formula.
price per ft^{2} = $200,000 ÷ 2,000 ft^{2} price per ft^{2} = $100
If you’d prefer not to do the math, you can also use our unit price calculator to calculate the price per square foot.
How many square feet is a 20×20 room?
The square footage of a room measuring 20 feet wide by 20 feet long is 400 square feet. To calculate this you simply multiply the width by the height. 20ft × 20ft = 400 sq ft.
Methods for how to calculate square feet for different shapes
Different shapes have different ways of calculating square footage. For all the shapes, it may be helpful to convert the measurement of the shape into square feet before making your calculation. Converting the measurements can help you keep the shape to scale, especially if the sides have different measurements, such as feet and inches or yards and meters. You could also perform the calculation and then convert the final measurement to square feet to achieve the same result.
Use the methods below to help you calculate square feet for seven different shapes:
How to calculate square feet for squares and rectangles
Squares and rectangles use the same formula to calculate square feet. This formula is:
A = length x width
In this equation, "A" is the total area of the shape in square feet. The length is the measurement of one side of the shape in feet and the width is the measurement of another side of the shape in feet. You can use the steps below to calculate the square footage of squares and rectangles with the formula above:
If necessary, convert your measurements for each side of the shape into feet.
Multiply the length and the width of the shape together to get the area of the square or rectangle in square feet.
How to calculate square feet for triangles
The square footage formula for triangles is:
A = 1/2 base x height
In this equation, "A" is the area of the triangle in square feet, "1/2 base" is the length of the bottom side of the triangle in feet and the height is the vertical distance from the bottom side of the triangle to the top corner in feet. You can use the following steps to calculate the area of a triangle:
Convert the measurements for the base and height into feet.
Divide the length of the base by two to get half of the base.
Multiply half the base by the height to find the square footage area of the triangle.
How to calculate square feet for circles
To calculate the area of a circle, it's necessary to use the number pi, which is represented by the symbol π. You can use the decimal 3.14 to represent the value of pi. The formula to calculate the square footage of a circle is:
A = π x radius2
In this equation, "A" is the total square footage, π is equal to 3.14 and the radius is the distance from the exact center of the circle to the outside edge in feet. To calculate the area of a circle, use the following steps:
If it isn't already in feet, convert the measurement for the radius into feet.
Multiply the length of the radius by itself to get feet squared.
Once you've calculated the square feet of the radius, multiply that result by pi to get the total area of the circle in square feet.
How to calculate square feet for trapezoids
To calculate the square footage of a trapezoid, you can use the formula:
A = [(base length + top length) / 2] x height
In this equation, "A" is the total area of the shape in square feet. The base length is the length of the bottom of the trapezoid in feet, and the top length is the length of the top of the trapezoid in feet. The height is the vertical distance from the base length to the top length of the trapezoid in feet. You can use the following steps to calculate the area of a trapezoid:
If necessary, convert the measurements for the base length, top length and height into feet.
Add the base length and the top length together to calculate the area for the nonrectangular sections of the trapezoid created by the diagonal sides.
Divide the sum of the base length and the top length by two to ensure you account for the diagonal sides in the equation.
Multiply that result by the height to find the area of the trapezoid in square feet.
Related: Rules of Multiplication: Definition and Examples
How to calculate square feet for rhombuses
To calculate the square footage of a rhombus, you can use the following formula:
A = distance from one pair of opposite angles x distance from the other pair of opposite angles
In this equation, "A" is the area of the rhombus in square feet and the distances from both pairs of opposite angles are in feet. You can calculate the area of a rhombus using the following steps:
Convert the measurements for the distances of the rhombus into feet if necessary.
Multiply the interior lengths, which are the distances from opposite angles within the rhombus, to find the area in square feet. The interior lengths intersect with each other at the center of the shape.
How to calculate square feet for parallelograms
To calculate the square footage of a parallelogram, you can use the formula below:
A = base x height
In this equation, "A" is the area of the parallelogram in square feet, the base is the length of the bottom side of the parallelogram in feet and the height is the vertical distance from the base of the parallelogram to the top side in feet. You can calculate the square footage of a parallelogram using the steps below:
If necessary, convert the measurements for the base and height into feet.
Multiply the base by the height of the parallelogram to find its area in square feet.
Measuring for Schluter Profile Edging
Measure the length of any outside edge where your tile edge would be exposed. Not all edging is the same. Speak to your design associate about different uses.