For a building with a gable roof measuring 300 feet by 300 feet and a pitch of 3/12, what is the effective roof area for drainage calculations?

To find the effective roof area for drainage calculations, you need to consider both the dimensions of the building and the pitch of the roof. In this case, the building has a gable roof, which means it has two sloped sides that meet at the peak.

First, calculate the horizontal projection area of the roof, which is simply the length times the width of the building. For a 300-foot by 300-foot building, this means:

[ \text{Horizontal area} = 300 , \text{ft} \times 300 , \text{ft} = 90,000 , \text{sq ft} ]

Next, you must account for the roof pitch, which is expressed as a ratio (3/12). This means for every 12 horizontal units, the roof rises 3 vertical units. To find the slope of the roof, we can calculate the rise using the Pythagorean theorem. The length of the roof (the hypotenuse) is crucial for drainage calculations.

First, calculate the length of the roof's slope (hypotenuse) for one side of the gable. The rise is 3 units for every 12 units of run. The actual length of