We’ve added support for the Main Wind Force Resisting System (MWFRS) Directional Procedure to the ASCE 7-22 and ASCE 7-16 wind loads calculators.
This feature calculates direction-specific wind pressures on walls and roofs in accordance with ASCE 7 Chapter 27, helping engineers evaluate building response based on wind orientation.
Key capabilities
• Directional wind analysis — Choose N-S (normal to ridge) or E-W (parallel to ridge) wind direction.
• Automatic geometry mapping — Building dimensions are converted to L and B based on wind direction.
• ASCE-based Cp values — External pressure coefficients are applied using Fig. 27.3-1, including interpolation for L/B, h/L, and roof slope.
• Accurate velocity pressures — Calculates q_z and q_h using exposure and topographic factors.
• Surface-specific design pressures — Generates positive and negative internal pressure cases for each surface.
• Windward wall pressure variation — Uses height-dependent velocity pressure (q_z).
• Minimum pressure checks — Applies ASCE 7-22 minimum pressures where required.
How it works
Select MWFRS (Directional Procedure) in the wind template.
Choose the wind direction (N-S or E-W).
The calculator determines directional building ratios (L/B, h/L) and roof angle conditions.
Cp values are taken from ASCE Fig. 27.3-1.
The tool computes design wind pressures for walls and roof surfaces.
This provides a clearer way to evaluate direction-dependent wind loading for MWFRS design directly inside the wind loads template.
Based on ASCE 7-22 Chapter 27 (Directional Procedure).
The optional Cp reduction noted in Fig. 27.3-1 (b) is not applied.
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