Roof type
Roof footprint
Flat, Symmetric gable, Single slope
Roof Area Calculator
Estimate flat or pitched roof surface from a footprint.
Open this toolA pitched roof has more surface than its horizontal footprint. Using the footprint alone can understate the material requirement.
Enter the simple roof geometry, pitch and horizontal overhang. Use a measured layout for roofs with valleys, dormers or several intersecting planes.
Inputs and controls
Measurement unit
Roof footprint
Feet, Metres, Inches, Centimetres, Millimetres
Building length
Roof footprint
Allowed range: 0.001 to 100000
Building width
Roof footprint
Allowed range: 0.001 to 100000
Horizontal overhang each edge
Roof footprint
Allowed range: 0 to 1000
Pitch angle
Pitch · degrees
Allowed range: 0 to 75
Ordering allowance
Pitch · %
Allowed range: 0 to 100
Added once to the measured requirement.
Covering quote
Pitch · PKR / sq ft
Allowed range: 0 to 1000000000
Optional. Enter your own supplier quote.
How to use
- Choose roof type and measurement unit. Enter building length, building width and horizontal overhang each edge.
- Enter pitch angle, ordering allowance and covering quote.
- Select Calculate estimate. Read the returned values alongside the assumptions below before copying, exporting or acting on the result.
Why use this tool
The calculation makes the effect of pitch visible before you compare roofing coverage or coating quantities.
Before relying on the result
Assumes simple planes with no dormers, valleys or roof openings. Enter horizontal overhang.
Tool limitations
Assumes simple planes with no dormers, valleys or roof openings. Enter horizontal overhang.
Questions
Can it handle every roof shape?
No. It assumes simple planes. Treat openings, valleys and complicated junctions through a measured roof schedule rather than a single footprint.
What should I check before using Roof Area Calculator?
Check Roof type, Measurement unit, Building length and Building width. Use the exact units shown beside the controls and replace any example values with your own inputs.
Source page last modified: 2026-10-01T14:08:57+00:00. This profile describes the tool; use its page to run it.
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