Balcony handrails are commonplace for large residential buildings, and they come in a variety of forms. While some are solid glass or metal, others may be more porous in nature, thus the design of these appurtenances for wind becomes more complex.

In the May 2022 SEU Session, Emily Guglielmo, SE, PE, from Martin/Martin Inc., presented Wind Loads: Updated Frequently Asked Questions. Emily explained how to deal with commonly encountered wind load situations that are not fully addressed in the code. She also identified the latest code updates and examined some complicated wind load provisions and how they relate to real world examples.

Emily noted that the most frequently asked question in regard to wind pressures that she receives is which wind load should be applied to these common balcony handrails. To hear her explanation for a reasonable rationale for the design of handrails, watch this short 4 minute video:

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url:         https://vimeo.com/724261154/f9b01f39d3

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src mod:     https://player.vimeo.com/video/724261154
src gen mod: https://player.vimeo.com/video/724261154?h=f9b01f39d3
src gen:     https://player.vimeo.com/video/724261154?h=f9b01f39d3&dnt=1

Using this approach, engineers can more accurately determine if the geometry of the handrail will induce a suction pressure on the leeward side, or whether the handrail acts more like a solid windward wall on the face of the building. Emily also provided an excellent resource to justify a reduction in the windward surface area for perforated materials which was developed by the chain link fence industry. This document indicates that a reduction can be taken unless the porosity of the material is less than 10% which would require the area be assumed solid.

Emily’s guidance helps clarify this often murky subject since the code does not give clear answers on wind loads for balcony handrails, and using the porosity of the material may help reduce these wind loads when applicable.