Square footage is the area of a space measured in square feet, calculated by multiplying length by width for rectangular areas. Essential for flooring, painting, material estimation, and real estate.
How to Calculate Square Footage
For rectangular rooms: Area = Length × Width (both in feet). For L-shaped rooms, divide into rectangles and add the areas. For triangles: Area = ½ × Base × Height. For circles: Area = π × radius².
Why Square Footage Matters
- Flooring: Determines how many boxes of tile, planks, or carpet rolls to buy (add 10% for waste)
- Paint: Walls are measured in sq ft to determine gallons needed (1 gallon ≈ 350-400 sq ft per coat)
- Real Estate: Price per square foot is the standard metric for comparing property values
- HVAC: Room size determines BTU requirements for heating and cooling
Real-World Example
An L-shaped living room: main section is 15' × 20' = 300 sq ft. The alcove is 8' × 10' = 80 sq ft. Total: 380 sq ft. For flooring at $4/sq ft + 10% waste: 380 × 1.10 × $4 = $1,672.
Frequently Asked Questions
How do I convert square feet to square meters?
Multiply square feet by 0.0929 to get square meters. For example, 1,000 sq ft = 92.9 m². To convert the other direction, multiply square meters by 10.764.
Does square footage include closets and hallways?
In real estate, it typically includes all heated/finished space — rooms, closets, hallways, and bathrooms. Garages, unfinished basements, and covered porches are usually excluded or listed separately.
How do I measure an irregularly shaped room?
Break the room into simple shapes (rectangles, triangles, semicircles), calculate each area separately, and add them together. For very irregular spaces, use the "grid method" — overlay a grid of 1-foot squares and count them.