How Insulation Affects Your Energy Bills
"Heating and cooling account for about 48% of the energy use in a typical U.S. home, making it the largest energy expense for most homes." Energy.gov
Since it has been proven that so much of our money is spent on us heating and cooling our house, why not make sure that we are getting the maxium efficiency from our heating and air conditioning system by ensuring that the energy produced by it is not wasted.
To better understand how energy moves in and out of your home:
a little science on the matter
There are three types of heat movement: conduction, convection, and radiation.
Conduction is the transfer of heat through solid objects.
"Since heat moves from molecule to molecule, it travels (or conducts) more quickly through dense materials than through loose materials. Dense materials, such as wood and metal, are called conductors, while loose materials, like fiberglass and plastic foam, are called insulators." Xcel Energy
Insulation slows the rate at which unwanted energy enters the home during the warm months and also slows the rate at which energy escapes the house in the colder months.
Convection is the transfer of heat through liquids or gases. Example: Wind blows through the gaps around a window or door transferring the cold air outside into the home.
To prevent energy loss by convection, any gaps in the thermal envelope of a house should be sealed such as gaps around windows, doors, switches and electrical sockets. Weather stripping and/or caulking around all of these gaps will keep warm air trapped inside the house.
Radiation is the transfer of heat through space in the form of electromagnetic energy. Example: Sunlight transfers heat into the home through a single paned window.
Radiant barriers are used in attics and air ducts to prevent energy loss by reflecting radiant energy and not allowing it into the home.
Check to make sure that your windows have low-E (low-emissivity) glass. If that is too costly of a repair you can use blinds or curtains to either block out the sunlight when you find your home too warm. Covering the windows when it is too cold will help to prevent the escape of heat through your windows to the outside.
How Do I Know If My Home Has Enough Insulation?
There are a few basic steps one can take to see if their home has enough insulation.
The first one? Make a trip to your attic! If it is as hot as the Sahara up there then more than likely have heat rising up from your home, making your furnace work overtime to keep the rooms below comfortable.
Another general approach is that there needs to be at least 12 inches of insulation in the attic.
According to the improvementcenter.com if you can see the floor joists (2-by-8 beams sitting on their sides) in the attic, you need more insulation. The same rule applies to any unheated basement.
If your home is more than 20 years old, then it is a good guess that you could benefit from adding more insulation.
This handy chart from energystar.gov lays out the suggested insulation according to region.
But what is 'R-value' and why do i need to know it?
Insulating materials are tested and given a Thermal Resistance Value (R-value)
"R-value measures resistance to thermal conduction; a material with a higher R-value per inch is a better insulator. Most types of insulation work because they have millions of pockets of gas trapped within their structure. These pockets slow heat transfer from high-energy, warm air molecules to low-energy air molecules on the other side of the wall. Fiber insulation, such as fiberglass and cellulose, relies on trapped air. The R-value of some foam insulation is enhanced by trapped gases: low-conductivity blowing agents. The insulation materials themselves—plastics in foams or wood fiber in cellulose—are also inherently resistant to conduction." Building Green
So to put it simply: the higher the R-Value, the more difficult it is for energy to move through the material by conduction, convection, or radiation.
But remember this! Even if your insulation has a great R-Value it won't do much if there are leaks and gaps around the house.
Now Why Does All Of This Matter To Me?
Living in Lubbock with West Texas climate means that one day the sun could be shining with a temperature of 75° and the next a frigid wind with a chill of 35°. With these random weather patterns we experience it is important to keep your home sealed as possible to prevent unwanted energy leaving your home, and wanted energy staying inside. The best way to do that: have a HVAC contractor test your home for escaping energy and proper insulation!
Call us today to schedule an energy audit of the home! We will do everything we can to ensure that the energy from your home system is not being wasted. There is no sense of airconditioning the neighbourhood outside ;)
Our certified contractors at Tim Johns Heating and Air will make sure that not only is your home and your family comfortable, but your wallet is as well.
