Planning & EstimatingQuestion 285 of 360
In estimating pipe for a run, why do experienced estimators add a waste/scrap allowance to the measured length?
a.Because the code requires exactly 25% extra
b.To account for cutoffs, defects, and field adjustments so the job does not run short
c.To inflate the price with no reason
d.Because pipe is sold only by the ton
Explanation
Real installations lose material to cutoffs, damaged ends, and field changes, so a small percentage is added so the crew does not run out mid-job. The allowance is a planning judgment, not a fixed code number. Too little risks shortages; too much wastes money, so estimators base it on the pipe type and job conditions.
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