Let’s say you have a roof that is 127 inches x 127 inches
Polycarbonate sheets of roofing material that are : flat like plexi-glass
48 inches x 96 inches (listed online this way)
Each one is $91.48
Corrugated polycarbonate sheets of roofing material (clear) corrugated is wavy
Each one is 2 feet by 8 feet (the store used to have these but now they don’t. I have some left over)
each one is $22.98
Which one is less expensive and how many will you need?
1st. you will need to find the area of the roof in square inches (length x width)
127 inches x127 inches = 16,129 square inches (do not convert to feet because you will have a remainder of square inches left over so you would have to convert it back to square inches anyway.
2nd. Take the flat roofing material and find the area in square inches
48 inches x 96 inches = 4608 square inches
Now find how much it costs per square inch
$91.48 / (divided by) 4608 square inches= $.01
3rd. Take the corrugated roofing material,
The size is only listed in feet so you have to convert it to square inches first.
2 feet = 24 inches and 8 feet = 96 inches
24 inches x 96 inches = 2304 square inches
Now find how much it costs per square inch
$22.98 /(divided by) 2304 square inches= $.009
The corrugated roofing material is $.009 per square inch
The flat roofing material is $.01 per square inch
.009 is less than .01
.01 is 1 hundredth
.009 is 9 thousandths
You can convert it to feet I guess but you will never get it exactly right!!!
To find how many you need
Take the area of the roof which is 16,129 square inches
Divide it by the area of one of the panels of the cheapest one which is the corrugated one
16,129 square inches / 2304 square inches= 7
So you will need 7 panels 7x $22.98 = $160.86
For the flat more expensive panels:
Area of roof 16,129 / 4608 square inches = 3.5
You only need 3.5 panels but you will have to buy 4 from the store so…
4 x $91.48 = $365.92
Thank goodness I still had some of the cheaper roofing material left over.
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