If you want to figure out the square feet within a certain room, begin by measuring the lengths of two adjacent walls (that is, two walls that share a common corner). Then convert the measurement into inches. For instance, if one wall is 8 feet 5 inches, you would execute the following equation: 8 x 12 (number of inches in a foot) = 96 96 + 5 = 101 inches.
If the other wall is 10 feet 7 inches, you would follow the same procedure: 10 x 12 = 120 120 + 7 = 127 inches.
Once you have the measurements of two adjacent walls, multiply these numbers together. If you were to use the example already given, the equation would look like this: 101 x 127 = 12,827 inches. In order to convert this number to square feet, divide by 144: 12,827 / 144 = 89.076 square feet.
In order to figure the square footage of multiple rooms or even an entire house, first figure the square footage of each individual room. Then add the totals for each room together. Here is an example: Den = 324 square feet Kitchen = 175 square feet Dining Room = 100 square feet Bedroom #1 = 120 square feet Bedroom #2 = 120 square feet Bedroom #3 = 256 square feet Bathroom #1 = 100 square feet Bathroom #2 = 100 square feet Closet #1 = 25 square feet Closet #2 = 25 square feet
Total Square Footage: 324+175+100+120+120+256 +100 +100+25+25 = 1,345 square feet