How’s the air flow in your home? Does it stay fresh and breezy? Or does the air get humid and still? Here is a brief discussion on how air circulates inside the home and a few tips on ways to improve circulation.
You may already know that hot air rises and cold air sinks. For this reason, higher areas, such as the second floor of a two-story house, or an attic, tend to get warmer easily. Hotter air is at a higher pressure than the surrounding cooler air, which causes it to rise and expand toward any openings around the enclosed space. Cooler air is at a lower pressure and sinks down to fill the space left by the rising hotter air. This cycle of air inside a building is called the “stack effect,” and is affected by the difference in temperature between inside and outside air.
Keeping the air circulating in your home is necessary to prevent the over-accumulation of dust and other harmful particles, and perhaps more importantly, the buildup of humidity and growth of mold and mildew.
Ventilation is essentially the replacing of stagnant air in the home with fresh air from outside.
Ventilation is different from the use and effect of a forced-air system, which controls how air is distributed throughout the building, as opposed to allowing the flow of air from the outside in.
Achieving and maintaining good air circulation in your home will likely call for a good balance between ventilation and forced-air control. The goal of “balanced ventilation” is to achieve and maintain a comfortable temperature in the home while keeping energy costs to a minimum. With many homes, reaching this goal usually involves the use of passive and mechanical ventilation in conjunction with a powered forced-air system (such as an air conditioner or heat pump) that is tuned to the home’s specific size and layout.
The leaking of air (in and out) can also affect air circulation in your home. For that reason, it’s important to be aware of and control how much air leaks in and out of your enclosed areas. “Infiltration” is a term used for the accidental movement of air from inside to outside a building (or from outside to inside). Many common leaks, such as around doors, vents, and piping can be remedied by adding insulating HVAC tape or foil to close small gaps where conditioned air escapes.
Even rearranging furniture and other objects can help the air flow better in your home. For one, avoid placing furniture over air vents in a way that blocks them. Second, avoid keeping too many large objects together in one spot, as this can block the natural flow of air through the different rooms of your home. Keeping common living spaces and walkways clear allows for easier circulation of fresh air to replace stagnant air. Ceiling and floor fans are also very helpful in keeping the air circulating in rooms where it tends to get stuffy.
If you need help getting the best air circulation in your home, consult your HVAC professional, who will be able to suggest the best ways to maintain the proper flow of fresh air in your home.