A flat roof replacement costs an average of $7,399
Flat roof replacement costs average between $4 and $35 per square foot for an average total of $7,399.
Roof size, style, materials, and local labor rates make up most of your total cost.
Premium materials or a tricky installation push costs to the top of the range.
A new flat roof improves energy efficiency and curb appeal.
Hiring professional roofers ensures long-lasting performance and reduced maintenance.
This article was updated using automation technology and thoroughly reviewed for accuracy by HomeAdvisor Editor Ryan Noonan.
Flat roof replacement costs an average of $3,326 and $11,521, which works out to $4 to $35 per square foot. The average total cost is $7,399. Your final price depends on the roof size, local labor rates, and the material you choose, so create a budget and hire a qualified professional before work begins. Careful planning now helps the new roof last longer and saves money down the road.
Roof size, style, and local labor rates drive most of your flat roof replacement cost. Here’s a closer look at how your total costs break down.
Roofers often price jobs by the ‘square,’ a 100-square-foot section. The cost per square foot varies depending on the materials used, your location, labor rates, and other project specifics. Low-end costs represent basic to standard materials and moderate labor requirements, while high-cost projects reflect premium roofing materials and complex installations.
Flat roofs don’t have slopes like other styles, so the size of the roof closely reflects the square footage of the house’s level below. Flat roofs involve a single, continuous layer of material with less labor-intensive framing.
Square Footage | Average Cost Range |
---|---|
1,000 | $4,000–$14,000 |
1,500 | $6,000–$21,000 |
2,000 | $8,000–$28,000 |
2,500 | $10,000–$35,000 |
3,000 | $12,000–$42,000 |
Flat roofs come in several variations in design, performance, and features. Each type carries its own respective costs. Some features are meant to improve energy efficiency or drainage by slightly manipulating the otherwise flat design or adjusting the insulation. Others, such as curved flat roofs, are mainly decorative and intended as an interesting architectural component.
Roof Type | Characteristics | Average Cost per Sq. Ft. |
---|---|---|
Cold | Basic design and less insulation | $4–$9 |
Warm | Insulation above roof deck for energy efficiency | $6–$11 |
Inverted | Insulation above membrane | $4–$9 |
Hybrid/compact | Combines warm and cold roof engineering | $4–$11 |
Curved | Curved design with flat roof panels | $8–$15 |
Tapered | Slight slope to improve drainage | $7–$10 |
Green | Vegetation planted over a waterproof system | $10–$35 |
Roofers charge an average of $3 to $7 per square foot for labor, roughly 20% to 30% of the total bill. Roof removal costs $1 to $5 per square foot or an average of $1,000 to $1,500. Prep involves removing debris, mold, or algae and repairing any damage.
Expect to pay more for labor for replacements with complex elements. For example, a simple flat roof doesn’t require advanced skills beyond basic roofing, but specialized flat roofs may require more experience, crew members, and overall time.
Difficult roof access requiring extra time, safety equipment, and scaffolding also creates extra labor costs. Some roof replacements necessitate additional site prep, such as mold remediation or structural repairs.
Permits and inspections are required for any project that modifies your home’s main structures, including the roof. Obtaining a permit for roof replacement costs $250 to $600, though this price may increase for larger roofs. Permit costs often cover roof inspections.
At the higher end of the range, premium roofing materials offer superior structural integrity, longevity, and weather resistance compared to lower-end types, as well as a luxurious aesthetic. Even so, certain materials are affordable, visually appealing, and durable.
Material | Average Price per Sq. Ft. (All-In) |
---|---|
Fiberglass | $4–$6 |
Modified bitumen | $4–$8 |
Built-up tar | $4–$10 |
Rubber | $4–$13 |
TPO | $4–$14 |
Fiberglass—also known as glass-reinforced polyester (GRP)—flat roofs average $5 per square foot or $500 per square. Fiberglass flat roofs are often double-layered for added strength and durability, and they last 20 years or more.
This budget-friendly material is lightweight and fire- and weather-resistant. Fiberglass roofs aren't recommended for large structures because they're prone to ponding across large areas, which strains the roof and risks cracking and leaking.
Modified bitumen roofs cost an average of $6 per square foot, ranging from $4 to $8 per square foot. This flat roofing type is notable for its light- and heat-reflective hue, as well as its 30-year lifespan. Modified bitumen requires skilled professional installation, as neglecting material seams can cause weak points and compromise your roof’s integrity.
Expect to pay an average of $7 per square foot or $4 to $10 per square foot to install a built-up tar flat roof. Made from multiple layers of felt and asphalt, this type of roof is fire-resistant, easy to maintain, and long-lasting.
Rubber flat roofs, also known as ethylene propylene diene monomer (EPDM), cost between $5 and $13 per square foot and resist damage from the sun, heavy snow, wind, and hail.
Roofs made from TPO, or thermoplastic polyolefin, average $8.75 and range from $4 to $14 per square foot. A type of modified rubber, TPO requires minimal maintenance, watertight sealing, and a long lifespan. It’s also known for energy efficiency, resistance to UV light and chemical degradation, and reflective qualities.
Deciding between flat roof replacement and repair depends on the roof’s general condition, the severity of damage, its age, and the cost of repairs. Depending on the materials used, repairs for flat roofs average $400. Repairing isolated sections of leaks, cracks in seams or joints, and other damage can be a cost-effective alternative to replacement.
If your roof has widespread damage, such as multiple leaks across different areas, issues with underlying layers, or significant overall wear, replacement can be a more effective solution than repair. This is especially true if your current roof is approaching the end of its expected lifespan. Replacement also provides an opportunity for aesthetic and energy-efficient upgrades.
Replacing a flat roof can increase your home’s value, with the actual return on investment depending on the roofing materials and local real estate market conditions. If your current roof is relatively new and in good condition, a new roof may have limited additional value. Otherwise, roof replacement comes with several advantages that appeal to potential homebuyers, such as:
Improved curb appeal
Enhanced energy efficiency
Reduced risk of leaks and water damage
Building code compliance
Lower home insurance premiums
Replacing a flat roof is a major investment, but these budgeting strategies can help manage your costs and ensure the quality of your project:
Request at least three written quotes that spell out material, demolition, disposal, and warranty costs.
Pick a roofing material that balances price, durability, and curb appeal.
Check for utility rebates or tax credits on energy-efficient roofing before you buy.
No place is more important than your home, which is why HomeAdvisor connects homeowners with local pros to transform their houses into homes they love. To help homeowners prepare for their next project, HomeAdvisor provides readers with accurate cost data and follows strict editorial guidelines. We surveyed thousands of real customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.
Clear your gutters after heavy storms or at least twice a year. If pines surround your home, bump that to every four months. Sweep loose debris off the roof whenever you see it, and schedule a professional roof and gutter cleaning when dirt starts to build up. Flat roofs trap leaves and standing water quickly, so staying ahead of clogs helps prevent leaks.
A well-maintained flat roof can last up to 25 years. Regular inspections, thorough cleaning of drainage systems, and prompt removal of debris help ensure that your flat roof remains durable and performs reliably throughout its lifespan. Maintaining tight seals and applying appropriate protective coatings further secures the roof’s integrity over time, making these essential practices vital for long-term performance.
Flat roofs offer significant advantages and present certain challenges. They deliver economic benefits through reduced material and labor costs, and they enable creative outdoor living configurations. However, flat roofs also exhibit disadvantages such as a tendency for water pooling, diminished attic space, vulnerability in snowy conditions, and an elevated risk of leaks if seals are compromised. Maintaining the roof with professional inspections and precise upkeep helps overcome these challenges.