Remarks on Olgyay’s Quotes About Irradiation on Curved Roofs

Abstract

This paper focuses on two quotes from Victor Olgyay's "Design with Climate" regarding the relationship between geometric properties and thermal performance in domes and vaults commonly used as roofs in warm regions. Specifically, the paper examines the statement that "the envelope of a hemispherical vault is roughly three times the surface of its base" and explores the assertion that "the radiation of high sun positions is diluted on a rounded surface". The study validates the first statement in geometric terms and then shifts attention to the latter, which has been extensively researched by various scholars. Building upon previous findings, the work confirms Olgyay's claim regarding insolation per unit surface area but challenges the assertion regarding total solar load. In fact, curved roofs receive more irradiation than horizontal roofs of the same footprint, depending on their Base to exposed Surface ratio. This correlation applies to all convex roof shapes, whether curved or not. © Copyright by Fundacja PLEA 2024 Conference, Wrocław 2024.