ASCE 7-22 ROOF C&C wind pressure calculation

VERSION

v1.1

STATUS

Stable

STANDARD

ASCE 7-22 Chapter 30 (C&C)

DESCRIPTION

This calculator determines design wind pressures for roof components and cladding (Zones 1, 2 & 3) based on ASCE 7-22, Chapter 30, Part 1 (h ≤ 60 ft). It is intended for informational purposes only. Results must be verified by a qualified professional engineer.

ASCE 7-22 Wind Pressure Calculator (Roof)

ASCE 7-22 Wind Pressure Calculator

Regular roof surfaces • Chapter 30 (C&C) • US customary units

Calculation scope: enclosed, partially enclosed or partially open, regular rectangular buildings; flat, symmetric gable, or regular hip roofs; mean roof height ≤ 60 ft; roof slope ≤ 45°. Open buildings, overhangs, parapets, rooftop equipment, canopies, unusual roof geometry and tornado design require other procedures. Confirm applicability, zone locations and the complete design with the structural engineer before use for construction. This calculator is not a certification of compliance.

Input Parameters

Project Name

Project Address

Design Method

Enclosure

Length (L) [ft]

Width / roof span (B) [ft]Span perpendicular to the ridge. For a regular hip roof, L ≥ B.

Roof Type

Exposure

Ridge Height [ft]

Eave Height [ft]

Mean Roof Height (h) [ft]Eave height when slope ≤ 10°; average of ridge and eave heights when slope > 10°. Calculated without rounding before checks.

Ultimate Wind Speed (Vult) [mph]Use ASCE 7-22 Vult for the site and risk category. Do not enter Vasd. ASD applies 0.6 to pressures once.

Topographic Factor (Kzt)Determine from site topography; do not assume 1.0 where speed-up applies.

Ground Elevation Factor (Ke)Use site ground elevation, not roof height. Limits Kzt 1–4 and Ke 0.5–1.2 are application limits, not universal code limits.

Effective Wind Areas [ft²]

Area 1

Area 2

Area 3

Area 4

Enter at least one positive area. Values below 10 ft² use the curve's small-area endpoint. Determine effective wind area for the component/connection; it is not necessarily panel area.

The building and roof fit the calculation scope above. The entered factors, exposure, enclosure and effective areas have been selected for this project.

Calculation Results

Enter project data to calculate.

Zone	Eff. Area	GCp (-/+)	Pos. Pressure [psf]	Neg. Pressure [psf]

Positive pressure acts toward the surface; negative pressure is suction. Zones are labels from the applicable figure; verify their locations before assigning loads to components.