Roof replacement costs an average of $4.75 per square foot, within a $3.75 to $11 range, according to Fixr’s February 2026 data. That is the number on every cost page, and it is easy to misuse, because it is measured per square foot of roof, not per square foot of your house, and roofers quote in “squares” of 100 square feet. This guide is about converting between those units so you can check a quote, then adjusting for pitch and complexity, then comparing materials. For a full asphalt-shingle cost breakdown, read our asphalt roof replacement cost guide.
Per Square Foot, Per Square, and Per House Square Foot
One square equals 100 square feet of roof surface. Multiply a per-square-foot price by 100 to get the per-square price (our arithmetic), so Fixr’s $3.75 to $11 range is $375 to $1,100 per square.
The trap is the denominator. Contractors, calculators, and cost sites do not all divide by the same thing:
- Per roof square foot: total price divided by actual roof surface. This is what Fixr’s $4.75 means.
- Per square: the same thing times 100. This is how roofers write estimates.
- Per house square foot: total price divided by floor area. This number is always higher, because a pitched roof has more surface than the floor under it.
Here is one quote converted all three ways. Say a 2,000 sq ft footprint at a 6/12 pitch. Our pitch factor of 1.118 gives 2,236 sq ft of roof, and about 5% more for overhangs (a common rule of thumb we also use in our asphalt guide) takes it to roughly 2,350 sq ft, or 23.5 squares. A $14,100 quote works out to:
| Unit | Calculation | Result |
|---|---|---|
| Per square | $14,100 / 23.5 | $600 |
| Per roof sq ft | $14,100 / 2,350 | $6.00 |
| Per house sq ft | $14,100 / 2,000 | $7.05 |
Same job, three numbers. Cost sites also differ in what they divide by, which is one reason published ranges disagree. Always ask what a figure is divided by.
Pitch Factors: How Slope Changes Your Square Count
Slope adds surface. The factor is the hypotenuse of the roof triangle, which is the square root of 1 plus the square of rise over 12 (our arithmetic). Multiply your footprint by it.
| Pitch | Factor | Roof area, 2,000 sq ft footprint | Squares | Area effect at $600/square |
|---|---|---|---|---|
| 4/12 | 1.054 | 2,108 sq ft | 21.1 | about $12,650 |
| 6/12 | 1.118 | 2,236 sq ft | 22.4 | about $13,400 |
| 8/12 | 1.202 | 2,404 sq ft | 24.0 | about $14,400 |
| 10/12 | 1.302 | 2,603 sq ft | 26.0 | about $15,600 |
| 12/12 | 1.414 | 2,828 sq ft | 28.3 | about $17,000 |
The $600 rate is an illustration, not a market quote, and the last column shows area alone. Fixr says steeper roofs increase total roofing square footage and need added safety measures that raise labor costs, without putting a number on it. Search summaries of several roofing-contractor sites put the steep-slope labor surcharge anywhere from 15% to 50% for roofs at 8/12 or 9/12 and above. We could not verify those figures at a primary source, so ask your bidders where their pitch surcharge starts and what it costs.
Complexity Matters Too
Fixr notes that hips, valleys, ridges, and dormers add labor time through extra flashing and seam work. Two roofs with the same square count can differ meaningfully in price. A plain gable is the cheapest shape. A cut-up roof with several dormers, a chimney, and skylights costs more per square, and a quote that charges the same per-square rate for both is either padding the simple roof or underpricing the complex one.
Cost by Material
Fixr’s February 2026 roof page gives whole-roof ranges for a 1,700 sq ft home with about 2,000 sq ft of roofing, but no per-square-foot figure by material. Dividing by 2,000 gives the per-sq-ft and per-square columns below (our arithmetic), so treat them as derived.
| Material | Whole roof (Fixr, ~2,000 sq ft) | Per roof sq ft | Per square | Lifespan (Fixr) |
|---|---|---|---|---|
| Asphalt shingles | $6,000-$10,000 | $3-$5 | $300-$500 | 20-30 years |
| Architectural shingles | $8,000-$32,000 | $4-$16 | $400-$1,600 | 20-30 years (asphalt) |
| Metal | $14,000-$38,000 | $7-$19 | $700-$1,900 | 50-70 years |
| Cedar shake | $10,000-$30,000 | $5-$15 | $500-$1,500 | not stated |
| Clay tile | $14,000-$28,000 | $7-$14 | $700-$1,400 | up to 100 years |
| Slate | $20,000-$60,000 | $10-$30 | $1,000-$3,000 | up to 150 years |
The architectural line is wide because Fixr’s range covers everything from basic to premium products on the same page. For metal, This Old House lists standing seam at $8 to $39 per sq ft and $800 to $3,900 per square, with a 50 to 80 year life, updated March 2026, so the top end depends heavily on the panel type. Our metal roof vs shingles guide compares the two most common choices in more depth. Heavy materials such as slate and clay tile may also need a structural check of the roof framing, which we could not source a price for, so ask your bidders.
What the Per-Square Price Usually Includes
Fixr puts labor at 40% to 60% of a roof job, or $4,000 to $6,000 on average. Its add-ons give you line items to look for in a quote:
- Tear-off and disposal: $50 per square on average, up to $150 per square for heavier materials.
- Underlayment upgrade: about $0.50 per sq ft for ice and water shield.
- Permits: $100 to $500.
- Solar panel removal and reinstall: $500 to $2,000.
If a quote says “$550 per square” without saying whether tear-off, underlayment, flashing, and ventilation are included, you cannot compare it with one that says “$650 per square all in.” Ask for a written scope with the same line items on every bid. Our contractor quote red flags guide lists what to push back on.
Checking a Quote in Five Minutes
- Measure the footprint, or take the figure from the listing or deed.
- Multiply by the pitch factor above, then add about 5% for overhangs.
- Divide by 100 for squares. Compare with the contractor’s count.
- Divide the total quote by squares to get the per-square price.
- Compare that with the material ranges above, adjusting for pitch, complexity, and what is included.
You can skip the arithmetic with our roof replacement cost calculator. If the roof is only partly damaged, see roof repair vs replace first, and if insurance is paying, read how coverage terms work in our homeowners insurance cost guide.
Bottom Line
Use $4.75 per roof square foot as a middle estimate, which is $475 per square, and expect $3.75 to $11 depending on material, pitch, and complexity. Always convert quotes to the same unit before comparing them, and measure your own roof area with a pitch factor rather than trusting your floor plan. For a 2,000 sq ft footprint at 6/12, the Fixr average works out to about $10,600 on 2,236 sq ft of roof (our arithmetic), before pitch premiums and decking repairs.
FAQ
How many square feet is a roof compared with the house?
It is larger. Multiply the footprint by a pitch factor: about 1.05 at 4/12, 1.12 at 6/12, 1.20 at 8/12, and 1.41 at 12/12. Then add roughly 5% for overhangs. Those factors are geometry, so they hold anywhere.
What is a roofing square?
A square is 100 square feet of roof surface. A 2,350 sq ft roof is 23.5 squares. Roofers quote prices per square, so multiply or divide by 100 to move between units.
Why is my quote higher than the per-square-foot average?
Common reasons are steep pitch, a complex roofline, two layers of old roofing, a premium material, or decking repairs. Check whether the cost page you used divides by roof area or floor area, since the second reads higher.
Is metal roofing worth the higher per-square-foot price?
Fixr says metal lasts 50 to 70 years against 20 to 30 for asphalt. If you plan to stay long enough to use that life, the cost per year can narrow. If you may sell in ten years, asphalt is the safer value.