Estimate Roofing Materials

A. Finished-Project Specification

Quantity: one completed roofing cost-code section in the Chapter 1 workbook containing a roof-plane schedule, field roofing quantity, starter, ridge and hip cap, underlayment, self-adhered membrane, drip edge, valley material, flashing schedule, penetration and ventilation schedule, fasteners and sealants, access and disposal items, labor, and dated pricing, reconciled against plan-view geometry and reviewed independently.

B. Roofing Component Schedule

Component	Basis	Contents	Preparation / Purpose
Roof-plane schedule	Section E, Steps 1–6	Plane ID, slope, plan-view area, slope factor, actual area, product, color, access	Establishes the actual slope area basis for every product quantity
Field roofing and starter	Section F, Steps 7–9	Squares, coverage rate, waste, starter linear feet	Prices the primary weather surface and eave/rake starter course
Ridge, hip, and valley	Section F, Steps 10, 14	Ridge cap, hip cap linear feet and coverage; valley assembly by length	Prices cap and valley material separately from field product
Underlayment and membrane	Section F, Steps 11–12	Underlayment area, laps, roll coverage; self-adhered membrane by location	Prices the secondary water barrier beneath the field product
Drip edge and flashing	Section F, Steps 13, 16	Drip edge linear feet at eaves and rakes; step, counter, apron, headwall, sidewall, cricket, kickout flashing	Prices edge protection and water-diversion details
Penetrations and ventilation	Section F, Steps 15, 17	Vents, skylights, chimneys, flues, curbs, fans; specified ventilation products	Prices roof penetrations and the specified ventilation system
Fasteners and sealants	Section F, Steps 18–19	Fastener schedule by product and slope; sealants, primers, adhesives, boots, collars	Completes the installed-system material list
Access, tear-off, and disposal	Section F, Steps 21–22	Scaffolding, lifts, roof jacks, fall protection, tear-off, dumpsters, magnetic cleanup	Prices access equipment and reroofing removal scope
Labor and pricing summary	Section G	Tear-off, preparation, membrane, underlayment, roofing, flashing, ridge, ventilation, cleanup labor; dated material pricing	Converts quantities and tasks into priced cost lines

C. Roof-Plane and Slope Reference

• Slope factor source: use the slope factor confirmed by the roof plan, elevation, or truss information for each plane; do not apply one slope factor to all planes without confirming each plane's pitch.
• Irregular planes: calculate dormers, crickets, triangles, trapezoids, and irregular planes as their own line items using the geometry shown in the plan set.
• Reconciliation requirement: compare total slope area against building footprint and roof geometry before proceeding to product calculations.
• Non-substitution rule: do not substitute an assumed slope for a plane whose pitch is not confirmed by the documents; record it as an open clarification instead.

D. Product and Formula Schedule

Line Item	Type	Formula Basis
Plane plan-view area, slope factor	Input	Entered directly from the plan set; source and slope basis required for every plane
Actual slope area	Formula	Plan-view area × slope factor, by plane, summed to total squares
Field roofing quantity	Formula	Total squares ÷ manufacturer coverage per unit, plus waste, converted to purchase unit
Starter, ridge, hip cap	Formula	Linear feet at eaves, rakes, ridges, and hips ÷ product coverage, plus waste
Underlayment, membrane	Formula	Area with laps ÷ roll coverage, plus waste; membrane areas calculated separately by location
Drip edge, flashing	Formula	Linear feet by condition ÷ stock length, plus waste
Fasteners	Formula	Squares × fastener schedule rate, by product and wind zone
Labor hours	Formula	Task quantity × production rate, by tear-off, prep, install, and cleanup task
Line total	Formula	Order quantity × unit cost, plus labor cost, plus equipment and disposal

E. Preparation — Documents, Systems, and Plane Setup

1. Review roof plans, elevations, sections, truss information, details, specifications, selections, and manufacturer instructions. Confirm the current revision against the Chapter 2 document register.
2. Identify covering, slope limits, deck, underlayment, ice barrier, ventilation, flashing, fastening, and warranty system. Record each on the roofing tab's system summary.
3. Separate roof planes by slope, product, color, exposure, and access. Assign each plane a unique identifier.
4. Calculate actual roof-plane area from approved dimensions and slope. Apply the confirmed slope factor to each plane's plan-view area.
5. Calculate dormers, crickets, triangles, trapezoids, and irregular planes separately. Do not fold irregular geometry into an adjacent plane's area.
6. Reconcile total slope area with footprint and geometry. Compare the summed slope area against an independent footprint-based estimate and resolve any variance before continuing.

F. Product, Accessory, and Flashing Takeoff Procedure

1. Calculate field roofing using actual product coverage. Divide total squares by the confirmed manufacturer coverage rate for the specified exposure.
2. Apply waste based on hips, valleys, dormers, cuts, pattern, handling, and attic stock. Record the waste percentage and its cause separately from the coverage calculation.
3. Calculate starter by eaves and rakes. Measure linear feet at each condition and convert using starter product coverage.
4. Calculate ridge and hip cap by length and product coverage. Measure ridge and hip lines separately from field roofing.
5. Calculate underlayment by area, laps, transitions, roll coverage, and waste. Include the full roof area plus required laps and transitions.
6. Calculate self-adhered membrane by eaves, valleys, walls, penetrations, and details. Price membrane separately from standard underlayment.
7. Measure drip edge separately at eaves and rakes. Record linear feet by condition and convert to stock length.
8. Measure valleys by specified assembly. Confirm whether the valley is open metal, closed-cut, or woven, and price the specified assembly only.
9. Count vents, skylights, chimneys, flues, curbs, fans, solar penetrations, and other openings. Record each by type, size, and location.
10. Measure step, counter, apron, headwall, sidewall, cricket, and kickout flashing. Record each condition by linear feet or count and specified material.
11. Calculate ventilation products from specified type and quantity without redesign. Use the ventilation quantity shown or specified in the documents; do not calculate a net-free-area design not provided by the specification.
12. Count fasteners by product, deck, slope, wind, starter, ridge, and flashing schedule. Apply the manufacturer or specified fastening schedule for each product and wind zone.
13. Include sealants, primers, adhesives, boots, collars, closures, and compatible metals. Confirm compatibility with the specified roofing and flashing system.
14. Include deck-repair allowance only when supported by scope. Do not include a deck-repair quantity without a documented basis from Chapter 2 or a field report.
15. Include tear-off, disposal, dumpsters, protection, and magnetic cleanup for reroofing. Confirm whether the project is new roofing or reroofing before pricing this line.
16. Include scaffolding, lifts, roof jacks, fall protection, loading, hoisting, tarping, and weather controls. Base access equipment on plane height, pitch, and site access.

G. Labor, Pricing, and Compatibility Review

1. Estimate labor by tear-off, preparation, membrane, underlayment, roofing, flashing, ridge, ventilation, and cleanup. Assign a production rate and crew to each task.
2. Adjust production for slope, height, complexity, temperature, wind, occupancy, and material. Record the adjustment basis for each affected task.
3. Price products from dated quotations confirming system, coverage, warranty, freight, and lead time. Record supplier, quote number, date, and expiration for every priced line.
4. Include rooftop loading, crane or conveyor, minimum order, and return restrictions. Confirm delivery method and any related charges.
5. Include permits, inspection, warranty registration, and manufacturer inspection where required. Confirm requirements against the specified warranty system.
6. Check compatibility among roofing, underlayment, flashing, fasteners, sealants, and treated materials. Confirm no incompatible product combination is priced into the worksheet.
7. Prepare the worksheet by plane, product, quantity, waste, labor, equipment, and total. Organize the roofing cost-code section so each plane and product line is independently reviewable.
8. Document deck, weather, ventilation, existing-layer, and access assumptions. Record each assumption in the workbook's assumptions and risk register, linked to the affected line.
9. Complete independent review of slope, valleys, penetrations, flashing, and waste. Have a second reviewer or an independent method confirm the highest-value and highest-risk quantities.