Roof Replacement Cost Estimator
*Estimates include a 10% waste factor. Prices vary by region and contractor.
How to Estimate Roofing Costs in 2024
Replacing a roof is one of the most significant investments a homeowner will make. Our Roofing Cost Calculator helps you generate a realistic budget by factoring in the critical elements that contractors use to bid on jobs: roof area, pitch steepness, and material types.
1. Understanding Roof Area vs. Base Area
Many homeowners make the mistake of assuming their roof area is the same as their home's square footage. However, the roof is always larger due to overhangs (eaves) and the slope of the roof.
The Pitch Multiplier: A steep roof has significantly more surface area than a flat roof covering the same footprint. Our calculator applies a "pitch multiplier" (ranging from 1.05 for flat roofs to 1.50 for complex, steep roofs) to determine the actual square footage required for materials.
2. Roofing Material Prices per Square Foot
The material you choose is the biggest variable in your total cost. Here is a breakdown of common options used in our calculation:
- Asphalt Shingles ($4.50 – $6.50 / sq. ft.): The most common residential roofing material. It is affordable and durable, typically lasting 20-30 years.
- Metal Roofing ($11.00+ / sq. ft.): Standing seam metal roofs are long-lasting, fire-resistant, and energy-efficient, though they come with a higher upfront cost.
- Tile and Slate ($16.00 – $22.00+ / sq. ft.): These heavy, premium materials can last over 50 years but often require structural reinforcement of the roof deck.
3. Labor and Tear-Off Costs
Labor typically accounts for 40% to 60% of the total project cost. Factors that increase labor costs include:
- Steepness: Roofs that are too steep to walk on require safety harnesses and scaffolding, slowing down the work.
- Tear-Off: Removing layers of old shingles adds dump fees and labor time. Expect to pay an additional $1.00 to $2.00 per square foot if tear-off is required.
- Waste Factor: Professional roofers always order 10-15% more material than the exact measurement to account for cutting and trimming around ridges, valleys, and vents.
Frequently Asked Questions
What is a "Square" in roofing terms?
Contractors often quote prices per "square." One square equals 100 square feet of roof area. If your roof is 2,000 sq. ft., it is a 20-square roof.
Does this estimate include flashing and underlayment?
The "Standard" and higher material selections in this calculator include an allowance for quality synthetic underlayment and standard flashing. However, custom copper work or extensive rot repair will add to the cost.