What is Insulation?September 17, 2019
What is Insulation?
Insulation is a tool to slow down the rate of heat transferring into or out of a building, and more commonly, our own homes.
Insulation is, essentially, the blanket that surrounds the house inside or on top of walls.
It traps and keeps the air movement throughout the home still to conserve a comfortable home.
Benefits of Proper Insulation
Insulation is key to affordably keep you and your family comfortable, as great insulation will keep the heat in or out depending on the outside temperature.
For example, if the outside air is sitting at a scorching 100 degrees Fahrenheit, proper insulation will keep the hot air out, while trapping the cool air inside at a comfortable temperature.
This process acts as a win-win; you will feel happier in your home and your air conditioning bill will keep to a minimum. This is a fairly simple explanation, but in fact, an insulation system can be quite complex as it has to do with the house layout itself.
For more information about how to save energy in your home visit: www.energy.gov/energysaver/energy-saver
Air, itself, is a great insulator. However, the problem is air moves throughout the home causing a difference in temperature relative to time. Heat moves around with the air to cause a fluctuation in overall cool air versus warm air.
This is where insulation comes into play; a good insulation material will stop and trap the air which moves throughout the home. This is the first step in understanding how insulation does its job.
In addition to the heat produced from the sun, heat can also be produced from people, animals, and lights inside the home. The heat generated by these sources moves through the home by three principles: Conduction, convection, and radiation.
These three modes of heat transfer will usually act together, simultaneously.
Types of Heat Transmission
Conduction is the method of heat transfer that acts and moves through solid materials. For example, if you place your hand on a hot car on a summer day, your hand will feel the heat from the car through conduction, your skin in direct contact with the car’s surface.
To feel this heat transfer, the two materials have to be at different temperatures, otherwise, no heat will transfer from one to the other. The heat flows from the warmer object to the cooler object via conduction.
There are companies that even make products that possess different thermal conductivity levels, for example, thermos water bottles that keep water cool or cookware to heat things more efficiently.
For more information about how thermos’ work visit: https://futurism.com/physics-thermos-heat-transfer
The next principle of heat transfer is called convection. This relies on the fact that warm air rises and cool air falls which transfers heat through the flow of air.
For example, if you boil a pot of water on a gas stove, the flame might not be touching the bottom of the pot, so how does the pot itself warm-up? This is convection at play through the flames. Heating the air between the flames and the pot so much that the heat is transferred to the solid material of the bottom of the pot.
Even though the flames and the bottom of the pot will never be in direct contact with each other, the bottom of the pot will heat up, thus boiling the water. This example can be the same as warm heat rising up through the home from the basement to the attic while the cooler air stays on the lower floors.
The result is a part of the “stack effect,” which we will go over in more detail in later blogs.
Radiation is the third method of heat transfer which doesn’t require any solid, liquid or gas to be present. Heat moves by radiation through electromagnetic waves, usually, traveling at the speed of light.
So how does this happen, exactly? Things produce radiation when higher energy electrons in a high atomic level fall down to lower energy levels. The difference in energy lost is the result of radiation or, sometimes, light.
It’s a very scientific process that happens all throughout our galaxy. But for a simple example, it is the heat transferred from the sun to us, here on planet Earth.
For more information about these three heat transfer principles visit: http://coolcosmos.ipac.caltech.edu/cosmic_classroom/light_lessons/thermal/transfer.html
Check back next week as we go over the different types of insulation and the benefits of each!