Flat / Low-Slope Roof Cost Calculator
Estimate the cost of a flat / low-slope roof — enter your roof size and pitch to get a low-to-high installed price, the cost per square, and a materials-versus-labor breakdown. A flat / low-slope roof typically runs $5–$12 per square foot installed.
How much does a flat / low-slope roof cost?
Flat and low-slope roofs use membrane systems — EPDM rubber, TPO or modified bitumen — rather than shingles. Material cost is moderate, and the total depends mainly on the membrane you choose and how much detailing the roof has around drains, curbs and walls.
As an installed all-in figure, a flat / low-slope roof typically runs $5–$12 per square foot. On a 1,957 sq ft roof (about a 1,750 sq ft home at a 6:12 pitch) that is roughly $10,000–$23,500 before any unusual features. The estimate above lets you set your exact roof size, pitch, complexity and tear-off to tighten the range.
cost = roof area × $5–$12/sq ft (× complexity) + tear-off · roof area = footprint × slope factor
Typical service life for flat / low-slope is 15–30 years. Once you have a target number, compare it against real local quotes before you commit — and if you're sizing materials for a DIY job, the roofing material calculator gives you squares, bundles and a shopping list.
New roof cost by material
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Frequently asked questions
How much does a flat / low-slope roof cost?
A flat / low-slope roof typically runs $5–$12 per square foot installed, all-in. On a 1,957 sq ft roof that works out to roughly $10,000–$23,500. Flat and low-slope roofs use membrane systems — EPDM rubber, TPO or modified bitumen — rather than shingles. Enter your own roof size and pitch above for an estimate.
How long does a flat / low-slope roof last?
A flat / low-slope roof has a typical service life of about 15–30 years, depending on the product grade, your climate and how well it is installed and maintained. You're paying for usable roof space, simpler geometry, membrane options.
What drives the cost of a flat / low-slope roof?
The main factors are roof size, pitch, complexity (hips, valleys, dormers and skylights), and whether the old roof is torn off — tear-off and disposal add about $1–$2 per square foot. Steeper and more complex roofs cost more because the work is slower and needs more safety equipment.
What makes a roof cost more?
The biggest cost drivers are roof size, pitch (steep roofs are slower and need fall protection), the material you choose, the number of layers to tear off, and complexity — hips, valleys, dormers, skylights and chimneys all add labor. Local labor rates and permit fees also vary widely by region. The estimate here covers a standard job; unusual features can push it higher.
How long does a roof replacement take?
A standard asphalt-shingle roof on an average home is usually a one-to-three-day job for a full crew. Larger, steeper or more complex roofs, or premium materials like tile and slate, take longer. Weather, tear-off of multiple layers and any deck repairs can extend the timeline.