In this module, you'll learn why roof design is foundational to building a healthy, mold-resistant home—and why it should come before the floor plan. A well-designed roof protects your home from water intrusion, condensation, and extreme weather. You’ll explore best practices such as using large overhangs, avoiding valleys, planning for drainage, and minimizing penetrations. You'll also learn how attic design—whether conditioned or vented—affects insulation, HVAC layout, energy efficiency, and indoor air quality. By thinking through roof structure, slope, materials, and attic strategies early in your design process, you can prevent costly moisture issues and lay the groundwork for a high-performance home.