The roofing and deck material worksheets estimate different surface quantities. Roofing uses measured roof sections and pitch to estimate covering area and bundles. Deck material uses deck dimensions, the selected board’s labeled face width, joist spacing, and waste to estimate boards and a geometric joist count.
Inputs and results
The roofing calculator multiplies each section’s plan area by √(1 + (rise/run)²), totals the sections, and applies the entered waste allowance. Dividing that area by the product coverage per bundle and rounding up gives the bundle count. The results show area before and after waste, bundles, the waste factor, and individual section areas.
The deck material calculator calculates boards across the deck width using the face width associated with the selected board size. Waste applies before the whole-board ceiling. Joist count is a geometric count from deck length and entered spacing; the result also shows deck area.
| Roofing | Deck material | |
|---|---|---|
| Measurements | Plan dimensions and rise/run per section | Deck length and width |
| Entered assumptions | Product coverage per bundle and waste | Board size, joist spacing, and waste |
| Results | Surface area, whole bundles, section breakdown | Boards, geometric joist count, deck area |
| Separate takeoff | Underlayment, nails, ridge caps, starter strips, flashing | Beams, posts, fasteners, rails, balusters, footings |
Use the quantities within their scope
Use roofing for the covering-area question. Measure every plane and confirm the bundle coverage with the actual product; an entered waste percentage is a planning assumption. Use deck material for the board-width and spacing calculation. Confirm board dimensions and the project layout before ordering.
For supporting geometry, the roof pitch calculator converts rise/run, angle, and slope percentage; the square footage calculator calculates measured areas; and the stair calculator provides a separate stair geometry worksheet.
Neither worksheet designs structure, selects safe spans or spacing, checks code compliance, or accounts for every installation detail. Openings, flashing, structural members, access, and fall protection require separate project review.