Making Your Home Energy Efficient

Making your Home Energy Efficient

Timothy D. Coomes

Edgewood College

Prof: Susan Rustick

RENG 151 – Research Writing Term E

If you listen to the news or watch, any type of television you may have heard of a little thing called global warming.  Global warming as defined by Meriam-Webster is the increase in the world’s temperature that caused by the increase in certain gasses, such as carbon dioxide or CO2, in the atmosphere.  Our own homes that we reside in today contribute to that release of these gases with the use of fossil fuels.  Fossil fuels overall account for 90 percent of America’s energy consumption with almost 25% of that coming from residential energy use (Praznik, Butala, & Zbasnik-Senegacnik, 2014).  Today’s modern home relies heavily on sources of energy to provide a comfortable living space to the occupants.  America is on an energy binge with home construction.  Today’s homes are much larger than they use to be and require more energy to cool, heat and light.  With enhance technology people in general are using more energy-hungry devices such as computers, tablets and cellphones that require a constant charge or periodic recharging increasing electricity use.  In order to reduce the use of fossil fuels in homes we look at how the products in our homes can lead to a more efficient use of energy or the use of renewable energy.  Residential sustainable energy construction can reduce the use of fossil fuels, benefiting the environment and reducing energy costs to the consumer.

So how do we begin to look at a home and make it more energy efficient? Homebuilders do not take into consideration the buyer’s energy costs when developing plans to build homes.  Knowing what causes energy inefficiencies in a home, a buyer can have a say in what type of materials used by the builder.   Energy Efficient construction begins with the exterior surfaces of the structure.  The exterior of a structure, commonly called the shell, consists of the walls, roof, windows and doors.  The effectiveness of the shell determines the level of energy demand the structure will have.  Heat exchange through the shell places the highest energy demand on the structure.  Today’s homebuilder’s want to make the home as aesthetically pleasing to the consumer to entice them to buy the home and use extrusions or intrusions in the exterior walls to accomplish this.  These extrusions or intrusions usually require extra framing causing decreased insulation in corners that can lead to air leakage in the home.  

Air leakage is the exchange of air from the exterior of the home to the interior and can represent between 5% and 40% of home energy waste (Loftness, V, Etal, 2007).  Controlling air leakage in the home increases comfort, reduces wall damage to interior walls, reduces pest infestation, and saves on energy costs.  The most valuable asset to prevent air leakage is insulation.  In order to get the most out of your insulation though you must first look at your framing of the structure.  Builders use either 2x4’s or 2x6’s in the construction of the framing of residential properties.  Using 2x6 construction allows for the installation of a thicker layer of insulation compared to 2x4’s. The climate where your home is located can be a deciding factor on which style to use.  The more “cold days” you have the more economic sense it makes to switch to 2x6 construction.  After you choose the type of framing you are going to use, the next decision is what type of insulation you are going to use.  

Insulation comes in many forms, spray foam, fiberglass, wool, cellulose, and even straw bales in some construction.  The most productive insulation source is the use of foam insulation.  Foam insulation easily conforms to the structure, and fills cracks and voids in walls with ease.  The downside to using foam insulation is that it can become very expensive initial investment usually 3 to 4 times as much as traditional fiberglass insulation (Chiras, Dan, 2010).  However, spray foam increases the environmental friendliness of your home.  As in creates an air barrier it significantly reduces air leakage, saving you up to 40% of your home’s energy loss.  For this reason, your energy consumption will be significantly lower saving you money over the long run.  With the lower energy costs, you can count on your home benefitting on the resale market as energy rates increase.  Foam insulation offers a high-performance solution for efficient building envelopes, comfort, and a healthy living environment, which are all components of green building and design (Dergisi, 2011).  Blown-in cellulose is another type of insulation that is by far the “greenest” of insulations.  Cellulose is made from recycled newspaper, offers the lowest amount of energy to produce, and is inexpensive compared to spray foam insulation. Regardless of which type of insulation you choose to use correct application for the structure is important in order to get the most energy efficiency out of the product installed.  Whether it is spray foam insulation or blown-in cellulose, there would be a loss in efficiency of the insulation if done incorrectly.  If there were too little of a layer installed the insulation would allow air leakage to occur and defeat the purpose of installing it.  If too much were to be installed it would not allow enough air movement to allow the dwelling to vent properly (Dergisi, 2011).  

Windows and doors are just as important of a selection as the type of insulation to choose.  Windows and doors, unlike insulation, rated on their ability to conduct thermal heat transfer rather than prevent the transfer, can also be cause for energy loss.  Four basic parts make up windows, the glass, sash, frame, and the rough opening.  These four parts contribute to the windows efficiency rating regarding energy, and the most important is the type of glass used.  There are several types to choose from but the best energy saving type is glass that called low-e or low emissivity windows.  This type of glass has a very thin transparent coating that allows visible light to pass through the glass while at the same time blocks infrared light (heat) from passing.  The cost of the typical low-e windows, like spray foam insulation, requires a higher initial investment, but offers greater energy efficiency leading to greater energy savings over the long term.  It is estimated that the energy savings would be about 12% to 33% annually, whereas the overall cost would be between $60 and $200 more per window depending on size (Savings Project: Install Exterior Storm Windows with Low-E Coating, n.d.).

A quality roofing system also helps to improve efficiency and reduce energy costs for the home as well.  If you ever stood on a roof on a hot summer day, you can feel how hot it can get.  Heat from your roof makes your home air conditioner work extra hard to keep your home cool.  Installing a cool roof onto your home can lower the temperature of the roof by up to 50oF and save you money by using less energy.  A Cool roof is generally a roof that uses a reflective material to reflect the heat given off by the sun.  The make-up of cool roofs includes such things as reflective paint, highly reflective tiles or shingles, or a sheet covering (Tips: Energy Efficient Roofs, n.d.).  The increase in the use of cool roofs will benefit not only the homeowner, but the community as well by lowering the amount of production from power plants.  Even more sustainable would be what they call a “green” roof.  This is best on flat or shallow pit roofs and is a rooftop garden for a home.  

After you get past the shell of a residential unit, the next biggest energy waste is heating and cooling of the structure.  North America’s demand for heating homes requires an enormous amount of energy.  This energy consumed with by the use of fossil fuels can be broken down into four categories.  The first category is natural gas.  The use of natural gas equates to about 53% of fossil fuel usage in a home and is considered the most environmentally friendly of the fossil fuels.  Oil was once a highly used product in the heating of homes long ago, but due to innovation of more efficient and environmentally friendly ways to heat homes, it has declined in use in modern times.  The high efficiency furnaces and boilers of today are tremendously more efficient than in the past.  Older systems would only have an efficiency range between 56% and 70%, whereas today these have as high as 98% efficiency rating with means that they convert almost all fuel consume to heat the home into useful heat for you home.  Upgrading your furnace from 56% to 90% efficiency can save up to 1.5 tons of CO2 emissions per year if the house heated with gas and up to 2.5 tons per year if you heat the house with oil (Chiras, 2008).

The second most used source of energy in a home is electricity.  Although electricity is 100% energy efficient once harvested, the methods of harvesting electricity are environmentally damaging.  Electricity has a huge impact on a home’s energy consumption.  Often times, we use more lighting in our homes than required.  You can see this when you walk through your home and notice that a hallway light left on even though no one is walking down it or the TV in the basement left on while everyone was upstairs eating dinner. Consumers must monitor their energy products are on or off to reduce wasted energy consumption.  Lighting accounts for 20% of the average home’s electricity bill.  Using high efficiency light bulbs such as LED bulbs will reduce energy costs for the consumer.  LEDs can use up to 90% less energy than incandescent bulbs and last up to 25 times longer (Energy & Cost Savings, n.d.).