No national price is embedded. Compare proposals only when roof system, tear-off layers, deck repair, underlayment, ice barrier, flashing, ventilation, accessories, warranty, cleanup, and permit responsibility match.
01 / Formula
How this is calculated
Total = allowed area × material rate + measured area × labor rate + measured area × tear-off rate + fixed costs02 / Assumptions
What the estimate assumes
- ✓All rates are entered by you.
- ✓Roof area is actual sloped surface area.
- ✓Fixed costs capture work not included in area rates.
03 / Worked example
See the math in context
For 2,000 sq ft, 10% allowance, $2.50 material, $3 labor, $1 tear-off, and $1,500 fixed costs, the estimate is $15,000.
04 / Guidance
Clarify deck repair
Ask how damaged sheathing is identified, priced, authorized, documented, and replaced. An unknown-condition allowance should stay separate from known base scope.
05 / Guidance
Normalize proposals
Record manufacturer and product line, layers removed, underlayment and ice barrier, flashing replacement, ventilation, fasteners, starter and caps, cleanup, protection, warranty, and payment terms.
Questions
Frequently asked
Can I measure or inspect a roof by walking on it?+
Do not access a roof without appropriate training, equipment, conditions, and fall protection. Use plans, ground measurements, aerial reports, or a qualified roofing professional when direct access is unsafe.
Does this calculator approve a roofing system?+
No. Verify deck condition, slope limits, underlayment, ice-barrier, flashing, ventilation, fasteners, wind requirements, fire classification, local code, and the exact manufacturer instructions.
What should be measured separately?+
Break out each roof plane plus valleys, hips, ridges, eaves, rakes, walls, penetrations, dormers, low-slope transitions, and special membranes. Geometry alone does not create a complete roofing order.
Sources