Thermal Stratification is a result of poorly managed natural convection. Thermal Stratification is something very important to comfort, and yet often ignored in the heating and air conditioning of most homes and buildings. Most know that hot air rises and cold air falls. This why most people are uncomfortably cold in their basements, and uncomfortably hot on the 2nd floor of 2 story homes and buildings.
The same principal that makes a hot air balloon fly causes this phenomena in our homes and buildings. When air is heated, it becomes lighter and rises. When air is cooled it becomes heavier and falls. This really makes for some uncomfortable spots if not properly addressed.
One problem is when it is very cold outside. The windows become very cold, and consequently make the air directly in contact with them cold. This air, then colder than the rest of the air inside the home, falls to the floor. I often try to visualize it falling like water down a hill. When this cold air hits the floor, it then begins to run along the floor looking for a stairway to continue it's downward journey, or if travels to the center of the home where it is pulled in by a Return Air. This creates discomfort, because you (your feet and ankles to be precise) are in the path of this cold air.
The summer time problem is very similar. As hot air rises from hot windows, it finds it's way to the second story, often making it very hard to sleep.
A properly designed Duct system andZoning system(when necessary), address these problems. While we can not change the laws of nature, we can stop them from negatively affecting our comfort. Every home and building has it's own unique challenges. Please let us come to your place and give you a free evaluation of what it would take to get the right temperature in the right places all of the time.
Weber Refrigeration Heating and Air Conditioning