Cost engine
How much does flat roof replacement cost?
National price ranges for flat roof replacement, the unit pricing contractors quote from, and what the same job costs across local markets.
Model reviewed August 2026
Flat Roof Replacement cost
$6,000 – $28,000
Most homeowners pay around $13,500 for flat roof replacement, or $6–$16 per sq ft of roof area. Permit fees add $180–$700.
Estimate your job
Run your own numbers before scrolling — the same engine behind the ranges below.
Roofing squares needed
14.8
Includes 10% waste
- Roof area
- 1,344 sq ft
- Shingle bundles
- 45 bundles
- Underlayment rolls (4 sq)
- 4 rolls
Estimates only. Local pricing, site conditions and code requirements change the real number.
What homeowners reported paying
Invoice amounts submitted by homeowners nationwide, shown beside the model.
Price breakdown
| Budget scope | $6,000 |
|---|---|
| Typical project | $13,500 |
| Premium / complex | $28,000 |
| per sq ft of roof area | $6 – $16 |
| Permit fees | $180 – $700 |
| Timeline | 2-5 days of work, 2-6 weeks including permitting |
What drives the price
- Membrane type: modified bitumen, TPO or coating
- Tapered insulation to correct ponding
- Number of penetrations and curbs
- Tear-off layers
- Parapet and flashing detail work
Cost by state
The same scope priced through each state's labor, material and code load.
Most expensive states
Least expensive states
Flat Roof Replacement runs about 105% more in Hawaii than in Mississippi for an identical scope — almost entirely a labor and code-load difference.
State benchmark table
Low, typical and high flat roof replacement pricing in every state, from the same model as the ranges above.
| State | Low | Typical | High | vs US |
|---|---|---|---|---|
| Hawaii | $10,500 | $23,600 | $49,000 | +75% |
| California | $9,100 | $20,400 | $42,300 | +51% |
| New York | $8,500 | $19,100 | $39,700 | +42% |
| Alaska | $8,400 | $19,000 | $39,300 | +40% |
| Massachusetts | $8,200 | $18,500 | $38,400 | +37% |
| District of Columbia | $8,100 | $18,300 | $38,000 | +36% |
| New Jersey | $8,000 | $18,000 | $37,400 | +34% |
| Connecticut | $7,700 | $17,300 | $35,900 | +28% |
| Rhode Island | $7,500 | $16,800 | $34,900 | +25% |
| Washington | $7,500 | $16,800 | $34,800 | +24% |
| Oregon | $7,400 | $16,600 | $34,500 | +23% |
| Maryland | $7,200 | $16,100 | $33,500 | +20% |
| Illinois | $7,000 | $15,700 | $32,600 | +16% |
| Colorado | $6,800 | $15,200 | $31,500 | +13% |
| Florida | $6,800 | $15,200 | $31,600 | +13% |
| New Hampshire | $6,700 | $15,200 | $31,400 | +12% |
| Nevada | $6,600 | $14,900 | $30,900 | +10% |
| Pennsylvania | $6,600 | $14,800 | $30,700 | +9% |
| Delaware | $6,500 | $14,600 | $30,300 | +8% |
| Minnesota | $6,500 | $14,600 | $30,300 | +8% |
| Vermont | $6,500 | $14,600 | $30,300 | +8% |
| Maine | $6,500 | $14,500 | $30,200 | +8% |
| Virginia | $6,500 | $14,500 | $30,100 | +7% |
| Arizona | $6,200 | $13,900 | $28,900 | +3% |
| Montana | $6,100 | $13,700 | $28,400 | +1% |
| Wisconsin | $6,000 | $13,600 | $28,100 | 0% |
| Michigan | $5,900 | $13,400 | $27,700 | -1% |
| Utah | $5,900 | $13,400 | $27,700 | -1% |
| Louisiana | $5,900 | $13,300 | $27,500 | -2% |
| Texas | $5,900 | $13,300 | $27,500 | -2% |
| North Dakota | $5,900 | $13,200 | $27,400 | -2% |
| Idaho | $5,800 | $13,100 | $27,300 | -3% |
| Wyoming | $5,800 | $13,100 | $27,300 | -3% |
| Georgia | $5,800 | $13,000 | $26,900 | -4% |
| New Mexico | $5,700 | $12,900 | $26,700 | -5% |
| North Carolina | $5,700 | $12,800 | $26,600 | -5% |
| Ohio | $5,700 | $12,800 | $26,500 | -5% |
| South Carolina | $5,600 | $12,700 | $26,300 | -6% |
| Indiana | $5,600 | $12,500 | $26,000 | -7% |
| Alabama | $5,500 | $12,300 | $25,500 | -9% |
| Missouri | $5,500 | $12,300 | $25,500 | -9% |
| Tennessee | $5,500 | $12,300 | $25,500 | -9% |
| Iowa | $5,400 | $12,200 | $25,200 | -10% |
| Kentucky | $5,400 | $12,100 | $25,200 | -10% |
| South Dakota | $5,400 | $12,100 | $25,100 | -10% |
| Nebraska | $5,400 | $12,000 | $25,000 | -11% |
| Kansas | $5,300 | $11,900 | $24,700 | -12% |
| West Virginia | $5,300 | $11,900 | $24,600 | -12% |
| Arkansas | $5,200 | $11,800 | $24,400 | -13% |
| Oklahoma | $5,200 | $11,800 | $24,400 | -13% |
| Mississippi | $5,100 | $11,500 | $23,800 | -15% |
Cost by city
Same scope, adjusted for local labor, material and permit pricing. Each city also has a permit page.
Frequently asked questions
Do I need a permit for flat roof replacement?
In most jurisdictions this work is permitted and inspected. Requirements are set locally, so confirm the current application and inspection checklist with your building department before work starts.
How long does flat roof replacement take?
2-5 days of work, 2-6 weeks including permitting. Permit review and inspection scheduling are usually the largest source of variation.
What changes the price the most?
The largest cost drivers are membrane type: modified bitumen, tpo or coating; tapered insulation to correct ponding; number of penetrations and curbs.
Sources
Sources & verification
Model vintage August 2026. The links above are the issuing agencies' own pages — we publish them so you can confirm the current rule yourself, not as evidence that each fact on this page was re-checked with them today. Cost figures are modeled estimates based on national baselines adjusted for local labor and material pricing, not quotes. Permit rules change; confirm with the building department before starting work.