Friday, April 12th, 2019 by Logan Home Energy Services
Here are 6 laws of physics that govern the comfort and efficiency levels in your home:
1.) Heat Moves from More to Less
Cold is a MYTH. There is no cold—it is just less heat. There is less heat and more heat, and heat moves from more to less. The bigger the temperature difference (on different sides of a ceiling, duct, wall or floor), the faster it moves.
2.) Air Moves From Higher Pressure to Lower Pressure
And the greater difference in air pressure (on different sides of a ceiling, duct, wall, or floor), the faster it moves. This explains a lot. Since air carries heat, in or out, this proves to be very important.
3.) Heat Moves in Three Ways—Conduction, Convection, and Radiation
Conduction is when heat moves molecule by molecule through solid materials. An example would be when your attic is cold in the winter, it makes the drywall ceiling cold if you don’t have enough insulation. Heat from the room moves into and through the cold ceiling. This makes your room cold as heat is lost.
Convection is heat carried along by air (or water) movement. That’s how we heat our homes. We heat air with a furnace (or water with a boiler) and send that air (or water) to the rooms we want the heat in. But it also works against us when the air leaks out of the house and takes heat with it.
Radiation—all objects that are warmer than other objects around them emit heat in the form of infrared waves. They are either giving off heat or absorbing it. It’s how a radiator works. It’s how that hot drywall ceiling from that 125 degree summer attic radiates its heat into our rooms.
To combat conduction we use lots of different kinds of insulation in the right places. To combat convection we use many different methods to stop air flowing in and out of the house in hundreds of different places. To stop radiation we use radiant barriers, or insulation to stop the objects or surfaces from gaining or losing heat in the first place.
4.) Moisture Moves From More to Less, and Hot to Cold
We find a lot of “building durability” issues. That means mold and rot. Understanding what direction moisture is flowing and how a wall, ceiling, floor or roof can dry is important.
5.) Warm Air Holds More Moisture than Cold Air
Closely related to the last one, this explains condensation issues and many mold issues. It also explains something we are all familiar with—rain. A pretty powerful concept.
6.) Warm Air is Lighter Than Cold Air
Most of us know this already. It’s how a hot air balloon flies. When we heat the air in our homes, it rises to the top – a very significant fact because that’s why air leaks out.
Insulating and thoroughly air sealing your home can drastically reduce the negative effects of these 6 laws. If you are interested in learning more about the strategies we use to address these issues and make homes more comfortable and efficient, give us a call today.