Free Roof Size Calculator
Enter your address and get an instant roof measurement.
No drawing, no ladder, no measuring tape required.
Measured using high-resolution satellite imagery. Typically accurate within 5–10% of field measurements.
How it works
Understanding your roof size
Everything a homeowner needs to know before getting a roof replacement quote.
How roof measurement works from satellite imagery
Traditional roof measurement means someone climbs a ladder with a tape measure, or a contractor sends a drone over your property. Satellite roof measurement replaces both. High-resolution aerial imagery is analysed to identify the roof outline, the individual roof planes (called facets), and the angle of each plane. From that, the total roof area is calculated in square feet. Because the imagery is taken from directly overhead, the measurement accounts for the actual sloped surface area — not just the flat footprint of the house. A steep roof has considerably more surface area than the ground floor beneath it, and that difference matters when a contractor is ordering materials.
Roof square footage vs. roofing squares
Homeowners think in square feet. Roofing contractors think in squares. One roofing square equals 100 square feet of roof area, and every quote, material order, and labour estimate in the industry is priced per square. If your roof measures 2,200 square feet, a contractor will call that a 22-square roof. Most single-family homes fall between 15 and 40 squares.
Why this matters: knowing your square count before you call anyone lets you sanity-check a quote instantly. If a contractor says your roof is 40 squares and this tool says 22, that discrepancy is worth a conversation.
What roof pitch means and why it changes the price
Roof pitch describes steepness as a ratio of rise over run. A 4/12 pitch rises four inches for every twelve inches of horizontal distance. A 4/12 to 6/12 pitch is considered walkable — a roofer can stand on it comfortably. Anything above 8/12 requires harnesses, roof jacks, and considerably more time, which is why steeper roofs cost more per square to replace even though the material is identical. Pitch also affects the total surface area: two houses with the same footprint can have meaningfully different roof areas if one has a steeper pitch. That is why a satellite measurement that accounts for pitch is more accurate than simply measuring the outline of the house.
Estimating materials from your square count
Asphalt shingles are sold in bundles, and three bundles cover one square. So a 22-square roof needs roughly 66 bundles — plus a waste factor:
- 10% waste — a simple gable roof with few cuts
- 15% waste — a complex roof with many hips, valleys, and dormers
Waste accounts for cuts, starter strips, and ridge caps. Beyond shingles, a replacement also needs underlayment, drip edge, ridge vent, and fasteners — all of which scale with square count. Knowing your squares gives you a defensible basis for reviewing the material line item on any quote.
What a roof replacement typically costs
Typical national cost per square, including tear-off, disposal, underlayment, and labour:
- Architectural asphalt shingle — $400 to $550 per square
- Metal — roughly $600 to $900 per square
- Concrete or clay tile — often $700 to $1,200 per square
Regional variation is significant, driven by three things: local labour rates, disposal costs, and building code. Coastal and high-wind regions require enhanced fastening schedules, secondary water barriers, and wind-uplift ratings that push costs well above the national average. Cold-climate regions add ice-and-water shield requirements along eaves and valleys. Permit fees and inspection regimes vary by municipality.
A warning on cheap quotes: a bid that comes in far below these ranges is worth scrutinising. It often means a code requirement is being skipped — which becomes a failed inspection later, at your expense.
Roof size and your insurance claim
If you are filing a hurricane or hail claim, roof size is the foundation of the entire settlement. The carrier's adjuster measures the roof, applies unit pricing per square, and produces a scope of work. If their measurement is low, every downstream number is low too. Homeowners who know their own square count going into an inspection are in a much stronger position.
If the adjuster's number looks low: a figure materially below an independent measurement is grounds for a supplement request. In most states your policy entitles you to a settlement that restores the roof to code-compliant condition — which frequently costs more than the initial estimate assumes.
What this tool can and cannot tell you
This calculator gives you an accurate estimate of roof area, square count, and dominant pitch from satellite imagery — typically within 5 to 10% of a physical measurement. That is more than enough to sanity-check a quote or understand the scale of the job.
What it cannot do is assess condition. It cannot see:
- Whether your shingles are curling, cracked, or losing granules
- Whether the decking beneath is rotted or soft
- Whether flashing has failed around a chimney or valley
- Whether a prior repair was done badly
- Damage that occurred after the imagery was captured — the imagery date is shown with your results
For a claim, a permit, or a final contract, a licensed contractor still needs to inspect the roof in person.
Frequently asked questions
How accurate is the roof size calculator? +
Our calculator uses satellite imagery analysis and is typically accurate within 5–10% of the actual roof area. For insurance claims, permits, or contractor estimates, we recommend having a licensed roofer verify the measurements on-site.
What is a roofing square? +
A roofing square is a unit used by contractors. One square equals 100 square feet of roof area. If your roof is 2,000 sq ft, it is 20 squares. Contractors use squares to estimate materials and labor costs.
What does roof pitch mean? +
Roof pitch (or slope) describes how steep your roof is. It is expressed as rise over run — for example, 4/12 means the roof rises 4 inches for every 12 inches of horizontal distance. Steeper roofs cost more to install and replace.
Does this work for all roof types? +
Yes — the calculator works for gable, hip, flat, and most other residential roof types. Complex roofs with many facets, dormers, or additions may have slightly lower accuracy.
Is this tool free? +
Yes, completely free. No sign-up or account required. Just enter your address and get your results instantly.
Can I measure my roof without climbing it? +
Yes — that is exactly what this tool does. Using satellite imagery, we calculate your roof size from above. No ladder, no drone, no contractor visit required to get an estimate.
How many roofing squares does my house have? +
One roofing square equals 100 square feet of roof area. Enter your address above and we will calculate your square count instantly. Most single-family homes fall between 15 and 40 squares.
Can insurance companies use satellite roof measurements? +
Many insurance companies and adjusters use satellite measurement tools for initial estimates. However, for final claims settlements, a licensed contractor or adjuster will typically verify measurements on-site.
Does this work for tile or metal roofs? +
Yes. The calculator measures roof area regardless of roofing material — asphalt shingle, concrete tile, clay tile, or metal. Note that tile and metal cost more per square to replace than asphalt, so the cost estimate shown reflects architectural asphalt shingle pricing.
Does this work after a hurricane or storm? +
Yes, though accuracy may be slightly lower if the satellite imagery predates recent storm damage. The imagery date is shown with your results. For post-storm damage assessments, a licensed roofing contractor or public adjuster should inspect in person.
Is my address or personal information stored? +
Your address is used only to retrieve roof measurements from satellite imagery. If you choose to request quotes, your contact information is shared only with licensed roofing contractors through ProGuild. We do not sell your data.