Having only a blueprint for a new home doesn’t mean that a roofing contractor must put aside their high-tech roof measurement and estimating application and pull out the ol’ tri-ruler.
An app certainly can make it a lot easier to produce a roofing report and detailed cost estimate faster than you can say “win the job for the whole darn subdivision.”
CALCULATING THE AREA (ESTIMATED)
If you don’t want to do a lot of measuring, you can use your pitch calculation to get an estimated square footage of your roof:
- Once you have your roof’s pitch, divide the number by 12. (For example, if your roof’s pitch is 4 in 12, you would divide 4 by 12. This would yield 1/3.)
- Next, square your result. (If your number is 1/3, squared would yield 1/9.)
- After that, add 1 to your number. (1/9 + 1 = 10/9.)
- Next, figure out the square root of your new number. (The square root of 10/9 is 1.05.)
- Determine the square footage of one floor of your home. (For example, if you have a two-story home that’s 2,600 square feet, one floor would be 1,300 square feet.)
- Multiply this number by your most recent result to get the estimated square footage of your roof. (1,300 x 1.05 = 1,365 square feet.)
Things You Will Need
Square footage of your house
Pitch of your roof
Paper and Pen
This calculation will give a solid estimate for a single slope roof and a simple gable roof with a single pitch. For more complex roof lines with multiple pitch angles, it’s a little more complicated but the same steps can be followed; just break down the roof into separate sections with a different square footage for each different pitch angle.