Passive Cooling Strategies To Use In Conjunction With Your HVAC System
Modern technology such as the AC unit and furnace provide a great way to heat and cool your home, but they do have limitations. The main problem is that an AC unit will only cool a home once it has started to heat up, and a furnace will only heat a home once it has started to cool down. If you want to improve the function of your HVAC equipment, sometimes low tech options are your best choice.
Cement Walls and Thermal Mass Cooling
If you live in a warm climate where the nighttime temperature falls below your thermostat setting, you can use thick masonry walls to help keep your home cool during the day. The main benefit of thick masonry cement or stone walls is that they will take longer to heat up than thinner walls. Thus, the sun may pound down on your home for hours before your walls heat up enough to begin heating the inside of your home. Depending on the thickness of your walls and the amount of heat outside, it may take until early or mid afternoon before your home starts heating up from solar heat gain. This means that you will have less need to run your AC during the day to keep your home cool.
Thermal Lag
During the night, the cold outside air will cool your walls, and they will release heat into your home as they cool. This is what is known as thermal lag, so named because it takes several hours of absorbing heat from the sun before your walls start to heat your home. Even if this means that your home starts to heat up from the heat escaping from the walls, your AC unit will run much more efficiently during the cool night hours, so you still save money as compared to using your AC unit to cool your home during the hottest hours of the day. As your walls cool, they will prepare to repeat the same process the following day, and this without the need to tap into man-made fuel sources.
Not all homes will benefit from thermal mass cooling. For example, if the climate around your home stays warm through the night, than your walls will not have a chance to cool at night, so your home will stay warm day and night thanks to the heat trapped in the cement. Furthermore, if you have to contend with a cold winter, your walls will not have a chance to heat up enough during the day to release heat into your home at night. Instead, they will simply increase the time it takes to heat your home during the day. In any case, if you are looking for ways to improve the function of your cooling system, you should at least discuss whether thermal mass cooling can work for your home.
