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Introduction

Metal sill pans have been used beneath windows for centuries to successfully protect the openings into which we install them. But is there a better way? Fluid and self-adhered membranes can conform more easily to complex geometries (origami with metal is difficult!) and any membrane at the sill can be continuous with whatever membrane is used at the jambs, reducing risk. But can fluids reliably span the gaps at openings? And are membranes less durable than their metal counterparts? This short presentation discusses both approaches to detailing windows at the sill (metal and membrane), showing examples (photos and sketches) of each, and makes the case that membrane sill pans are typically the more reliable choice. About Building Science Fight Club

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Video: Is It Time to Retire the Metal Sill Pan

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Quiz

To earn AIA Continuing Education Units (CEU), you must complete the quiz below and get all 3 questions correctly. Feel free to retake the quiz if needed. To keep learning, check out more courses in Building Science.