4 Determine the number of sheets of roof decking required to

4. Determine the number of sheets of roof decking required to cover a roof that is 180 ft by 90 ft if each sheet is 42 ft long and 3 ft – 3 in wide. The decking length (42’) runs in the long direction of the roof and the panels are lapped 3” with the adjacent panels on each side. Use the rows and columns method, and assume that cut remnants are waste.

Solution

In the long direction direction, we need    180-42=138ft, So sheets required= 1+ 138/39.75=1+3.47=4.47, So 5 nos. So number of Rows=5

In width direction it is 3ft 3 in -3in overlap=3ft. Fisrst sheet =3ft3in rest all 3ft. So number of columns=1+(90-3.25=86.75/3)=1+28.91=29.91 So 30 nos in columns.

Total sheets=5x30=150