The floor space of a given room is the total area of the floor. Because most rooms are not one big square or rectangle, people sometimes worry about how to accurately calculate floor space. The best solution for calculating the floor space of a room is to break it up into smaller squares and rectangles and then measure the area of these smaller pieces. Once you have measured all the smaller regions, you can add them up to get a good idea of the floor area of the room. This will allow you to break up and measure even a complicatedlooking room.
Things You'll Need
 Measuring tape
 Calculator
 Paper and pencil

Break up the room into as many smaller rectangles as necessary, and measure the length and width of each one with the measuring tape. Write each set of dimensions on a piece of paper so you do not forget.

Multiply the length by the width for each rectangle. For example, if the room was divided into 4 rectangles with measurements of 5 feet by 10 feet, 4 feet by 2 feet, 5 feet by 6 feet and 7 feet by 2 feet, the areas would be, in order: 50 square feet, 8 square feet, 30 square feet and 14 square feet.

Add up the all the areas together to get the total floor space area of the room. Using the above example: 50 + 8 + 30 + 14 = 102 square feet.
References
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