The seal affixed to the lower edge of an exterior door, supplementary to a primary entrance, serves as a barrier against drafts, moisture, and insects. This component, typically made of rubber, vinyl, or felt, compresses when the door closes to fill the gap between the threshold and the door’s bottom edge. Different profiles and materials cater to various threshold types and door designs.
A properly functioning lower door seal is crucial for energy efficiency, preventing heat loss in winter and cool air escape in summer. This contributes to lower energy bills and a more comfortable interior environment. Furthermore, it safeguards against water damage by preventing rain and snowmelt from infiltrating under the door. Historically, simple felt or brush-like materials were used, but modern advancements in materials science have led to more durable and effective sealing solutions. These advancements reflect an increasing awareness of energy conservation and home comfort.