How to Prevent Ponding on Single-Layer ETFE Roofs
Single-layer ETFE roofs are lightweight, transparent, and well suited to long-span architecture, but their drainage behavior is different from that of rigid metal or glass roofs. On a shallow, nearly flat ETFE panel, the main risk is not simply that the nominal slope looks small. The critical problem is a local depression that develops under rain load: water collects, the membrane deflects further, and the deeper depression attracts more water. That feedback loop is the mechanism behind roof ponding. This guide uses the BIM model, detail drawings, measured dimensions, and on-site rectification records from a 1:1 ETFE mock-up for Qingdao Youth Football Stadium to answer a practical design-and-construction question: how can a project team reduce single-layer ETFE roof ponding risk before large-area installation begins? Scope and design boundary Every dimension and construction detail below comes from the Qingdao Youth Football Stadium ETFE mock-up. Other projects must be designed for their own local design rainfall intensity, span, support…
