Estimating the cost of a new roof or roof replacement can be a complex task, as many factors contribute to the final price. Our Roof Estimate Calculator helps you get a preliminary idea of what to expect based on common industry metrics.
Key Factors Influencing Roof Cost:
Roof Surface Area (sq ft): This is the most fundamental factor. Roofing materials are often priced and installed per "square," which equals 100 square feet. A larger roof naturally requires more materials and labor.
Material Cost per Square: The type of roofing material you choose significantly impacts the cost. Asphalt shingles are generally the most affordable, followed by metal, wood shakes, and then more premium options like tile or slate. This input represents the cost of your chosen material for every 100 square feet.
Labor Cost per Square: Labor costs vary by region, contractor experience, and the complexity of the job. This is the cost charged by roofers for installing 100 square feet of roofing.
Roof Pitch Factor: The steepness (pitch) of your roof affects labor difficulty and safety requirements. A steeper roof (higher pitch factor) often means higher labor costs due to increased time, specialized equipment, and safety measures needed. A factor of 1.0 is for a low-slope roof, while 1.5 or higher might be for a very steep roof.
Waste Factor (%): During installation, some material is inevitably cut off, damaged, or goes unused. This waste factor accounts for that extra material needed, typically ranging from 5% to 15% depending on the roof's complexity and material type.
Old Roof Removal Cost: If you're replacing an existing roof, the old layers need to be torn off and disposed of. This cost covers the labor for removal and dumpster fees.
Underlayment Cost per Square: Underlayment (felt or synthetic) is installed beneath the primary roofing material to provide an extra layer of protection against moisture. This cost covers the material and installation per 100 square feet.
Permit Cost: Most roofing projects require a building permit from your local municipality. These costs are fixed and vary by location.
Miscellaneous Fixed Costs: This category includes various smaller expenses like flashing, vents, drip edge, nails, sealants, and other consumables that are essential for a complete and durable roof system.
How to Use the Calculator:
Input your specific details into each field. If you're unsure about a value, use the default numbers provided as a starting point, which represent common averages for a standard asphalt shingle roof. For example:
Roof Surface Area: Measure your roof's footprint or consult your home's blueprints. Remember to account for overhangs.
Material Cost per Square: Research local suppliers or get quotes for your desired material. For standard asphalt shingles, $100-$200 per square is common.
Labor Cost per Square: This can range from $80-$150 per square, depending on your area and the complexity of the roof.
Roof Pitch Factor: A common residential roof might have a factor of 1.1 to 1.3. Very steep roofs could be 1.4 or 1.5+.
Waste Factor: 10% is a good general estimate for most shingle roofs.
Old Roof Removal Cost: This can range from $300 to $1000+ depending on the size of the roof and number of existing layers.
Underlayment Cost per Square: $15-$30 per square is typical.
Permit Cost: Check with your local building department. Often $100-$300.
Miscellaneous Fixed Costs: $200-$500 is a reasonable range for these smaller items.
Keep in mind that this calculator provides an estimate. For an accurate quote, always consult with licensed and insured roofing contractors who can assess your specific property and provide a detailed proposal.