Running out of bags on a roof is a wasted trip. Divide the gutter run by how much footage a bag holds, round up, and load that many before you leave the shop.
180 feet of gutter at 60 feet a bag is exactly 3 bags. Add a spare and take 4.
The example
Three houses on the day's route, with different debris loads per foot.
| A | B | C | D | E | |
|---|---|---|---|---|---|
| 1 | Property | Gutter (ft) | Ft per bag | Bags | With spare |
| 2 | Ranch home | 180 | 60 | 3 | 4 |
| 3 | Two-story colonial | 240 | 45 | 6 | 7 |
| 4 | Townhouse | 95 | 60 | 2 | 3 |
The formula
ROUNDUP again — a partial bag is still a bag you had to bring:
How it works
The only judgement call is the middle column:
B2is the total gutter run measured off the house or the estimate.C2is how many feet of gutter fill one bag — 60 under light tree cover, closer to 45 under heavy pine or oak.ROUNDUP(...,0)gives whole bags.=D2+1adds the spare that keeps you off a second trip.
Adjust the feet-per-bag figure seasonally. A spring cleaning after leaf drop fills bags roughly twice as fast as a midsummer maintenance visit.
Try it: interactive demo
Enter the gutter run and how much footage a bag holds.
Variations
Bags for the whole route
Total the day rather than the stop.
Bag cost into the quote
Small consumables add up over a season.
Pitfalls & errors
Measure the gutter run, not the roof perimeter. Gable ends usually have no gutter, and counting them inflates every estimate on the route.
Wet debris weighs several times what dry debris does. Bag capacity here is about volume — check that a full bag is still liftable off a ladder.
Practice workbook
Frequently asked questions
How do I calibrate feet per bag?
What about blower-and-tarp crews?
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