A high quality door seal is another important aspect of a well-designed cellar. If there is a gap between the bottom of the door and the floor, the cool air will sink and flow out beneath the door. While the release of the cool air may be subtle, it will require the WhisperKool unit continue to operate without achieving the desired results. Use good-quality weather-stripping and seals around the cellar door to prevent cool air leakage. See the Guide to Wine Cellar Construction for more details.