How is the perimeter estimate of a gable roof calculated?

The perimeter estimate of a gable roof is correctly calculated using the formula that incorporates the rakes (the sloped edges of the roof) and the eaves (the horizontal edges of the roof) along with a slope factor, which accounts for the pitch or angle of the roof.

This approach considers both the vertical and horizontal components of the roof's perimeter, ensuring a comprehensive estimate. The rakes contribute to the total slope of the roof, while the eaves provide the necessary horizontal measurement. By multiplying the rakes by the slope factor and then adding the eaves, this calculation accurately reflects the full perimeter required for materials estimation, such as for roofing shingles, underlayment, or flashing.

Other methods suggested in the options do not adequately account for the required factors or misapply the relationship between the components, resulting in inaccurate representations of the roof's perimeter.