Height x width of each side x 2 to get total square feet. If you have a hip roof it's half of width x height per hip on the end that comes to a point. If it is just angled on the ends and long flat spot along top then it's height x length measured to the start of angle on other end but not including it.
how do you figue out the square footage of something like a roof for example. thank you in advance for anyone one who can help me out
Measure the length and the width(height)
for example: If the length is 20 feet and the height (from near the gutter to the roof ridge) is 10. This would be one side of a standard house. Then it would be 20 times 10 = 200. This would be 2 square. 100 square feet roofers call that 1 square.
An average house (2000 square feet interior/2 story) has about 15 square of roof if it has two roof surfaces and the slope of the roof. A steeper slope would require more material.