I have a pole barn,that its walls are 15ft tall each collum span is 8 ft. total sq.ft. to coverthe roof and walls

Is this a trick question? Because if it's 15' tall, you might want to sacrifice a foot off one sheet. So, take perimeter and divide by 4 and multiply by 2. 4' per sheet and 2 sheets per 15' panel

The roof, you can't tell without knowing the dimensions of the building, and the pitch.

Now you would be able to tell how many sheets is 2400 sqft, but I don't know if the 2400 sqft is the size of the building or the amount to cover.

Totally confused unless it's homework.

75 sheets