Gazebo Roofing Calculator

Calculator Inputs

Unit system

Inputs convert automatically for results.

Gazebo length

Enter a valid length.

Gazebo width

Enter a valid width.

Overhang (each side)

Adds to both length and width.

Roof style

Hip/pyramid uses a practical area factor.

Waste allowance (%)

Typical: 8–15% depending on cuts.

Pitch input

Choose one method for roof slope.

Pitch rise (per 12)

Example: 4 means 4/12 pitch.

Pitch angle (degrees)

Example: 18° is a moderate slope.

Roofing material type

Defaults fill coverage if left blank.

Coverage per unit (area)

Leave empty to use smart defaults.

Price per unit

Set to estimate material cost.

Underlayment coverage (%)

100% means full roof coverage.

Underlayment roll coverage (area)

Common rolls: 200–400 ft².

Price per underlayment roll

Ridge cap piece length

If no ridge, this is ignored.

Price per ridge piece

Drip edge price (per linear ft)

Fasteners rate (per area)

Example: 1.2 fasteners per ft².

Labor cost (per area)

Tax (%)

Example Data Table

Length	Width	Overhang	Style	Pitch	Waste	Roof area	Units needed
12 ft	10 ft	0.5 ft	Hip	4/12	10%	≈ 163.6 ft²	10 panels (18 ft² each)
3.6 m	3.0 m	0.15 m	Pyramid	18°	12%	≈ 17.2 m²	19 bundles (33.3 ft² each)

Examples use rounded values and typical coverage defaults.

Formula Used

Effective footprint: L_eff = L + 2·Overhang, W_eff = W + 2·Overhang.
Pitch angle: θ = arctan(Rise/12) or θ = Degrees·π/180.
Area factor: Factor = 1 / cos(θ).
Hip/Pyramid roof area (practical): Area ≈ (L_eff·W_eff) · Factor.
Gable roof area: Run = W_eff/2, Slope = √(Run² + (Run·Pitch)²), Area = 2·(L_eff·Slope).
Waste: Area_w = Area · (1 + Waste%/100).
Units: Units = ceil(Area_w / CoveragePerUnit).

How to Use This Calculator

Choose feet or meters, then enter gazebo length and width.
Add overhang to match your planned eave extension.
Select roof style and pitch, then set a waste percentage.
Pick a material and adjust coverage if your product differs.
Optional: add prices for a full cost estimate with tax.
Click Calculate, then export CSV or PDF if needed.

Calculator Inputs

Example Data Table

Formula Used

How to Use This Calculator

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