Roofing Calculator
Estimate roof area and number of tiles (or slates) needed. Add pitch factor for slope. Free.
~1.1 low pitch, ~1.2–1.4 typical, ~1.5 steep
Common UK ~60
Roofing calculator
Use this roofing calculator to estimate roof area and how many tiles or slates you need. Enter the length and width of the roof (e.g. ridge to gutter and span), and a pitch factor to allow for slope. Optionally set tiles per m² for your product. The result includes about 15% for waste and overlap. For complex roofs, measure each plane and add areas.
Frequently Asked Questions
How do I calculate roofing materials?
Enter the roof area (or length × width and pitch). The calculator gives the area to cover and suggests number of tiles/slates and rolls of felt or underlay. Add 10–15% for waste and overlap.
What is roof pitch and how does it affect area?
Pitch is the angle or slope. A steeper roof has more surface area than the floor plan. The calculator can use a pitch factor: e.g. 1.2 for low pitch, 1.4 for steeper. Or enter the actual measured roof area.
Is the roofing calculator free?
Yes. Free to use. For estimating only; check with your supplier for exact quantities.
How many roof tiles per m²?
Depends on tile size. Common UK tiles need about 60 per m² (or 10 per sq ft). The calculator uses a default you can adjust.
Related
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<p>Calculator: <a href="https://onlinecalculator.co.uk/specialised/roofing-calculator" target="_blank">Roofing Calculator</a> - OnlineCalculator.co.uk</p>APA Style Citation:
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