In estimating shingles allow nine to the square foot when laid 4½ inches to the weather, and eight to the square foot when laid 5 inches to the weather. Common shingles are estimated to average 4 inches wide, and 250 are put up in a bunch, there being four bunches to the thousand.
Dimension shingles are usually 5 or 6 inches wide, 150 to 180 being put in a bunch, and four bunches counted 1000. In reality there are not 1000 shingles, but being wider than the average of common shingles they are counted the same. There is more waste in laying dimension shingles than the common ones. One-eighth should be allowed for waste in laying dimension shingles.