Question 1

How do I calculate roof area?

Accepted Answer

For pitched roofs, multiply floor area by a pitch factor (1.0 for flat to 1.5+ for steep).

Question 2

How much extra roofing material should I buy?

Accepted Answer

Order 10-15% extra for waste, valleys, and mistakes. Complex roofs may need 20% extra.

Question 3

How do I visualize large area units?

Accepted Answer

An acre is about 90% of a football field. A hectare is about 2.5 acres. A square kilometer is 100 hectares or about 247 acres.

Question 4

Why are there so many area units?

Accepted Answer

Different regions and industries developed their own units. Acres for farming, hectares for international use, square feet/meters for construction.

Roofing Area Calculator - Free Online Tool

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