Increase comfort and efficiency with the right windows A building’s envelope is the physical barrier between the interior and exterior environments. It includes all of the elements that contribute to keeping conditioned indoor spaces dry and comfortable. When thinking about the envelope, the first things that come to mind are the roof, walls, foundation, insulation, and assorted types of waterproofing. However, it’s also important to consider how critical windows are for the durability, energy efficiency, healthiness, and livability of a building. Beyond providing natural light, windows have a central role in keeping moisture, air, and heat outside or inside of the building—depending on the season. Heat There are three ways that heat energy is transferred from a warm place to a cool place: radiation (sunlight), convection (hot air movement), and conduction (heat transferred through materials). R-values indicate how effective the insulation and building materials are at controlling heat transfer through…