Assess Your Nest: Home Energy Audits
Editor’s Note: We asked our regular freelance writer Jenn Ballentine to have an energy audit performed on her home. Energy audits (or assessments) are a new trend for homeowner looking to save money and make their home more energy efficient. This is Jenn’s first person account of the process and results.
By Jenn Ballentine
As a freelance writer and consultant, I work from home and am particularly attuned to the varying comfort levels of my 1910 Craftsman in Virginia Highland. Given that my home is 100 years old and still contains all of the original lead glass windows, two of the five original coal-burning fireplaces and some of the original plaster walls it is very drafty and cold in the wintertime. In the summertime, it is difficult to maintain a comfortable temperature, particularly when we entertain and have more people than usual in the house.
Joe Thomas and Steve Herzlieb of Renewal System Solutions (a sister company of Renewal Design Build) conducted a Home Performance with ENERGY STAR Assessment on my home looking for air leakage, inadequate insulation, leaky heating and cooling systems and ineffective moisture control.
Thomas and Herzlieb conducted a number of diagnostic tests using sophisticated equipment to accurately measure the air infiltration (“draftiness”), duct leakage, pressure differentials, carbon monoxide levels and gas leakage in my home. They applied an integrated, whole-house approach in order to adequately diagnose problems and identify solutions. Specifically, they inspected the building envelope and air tightness, the insulation, the windows, the ductwork, the lighting and appliances and the mechanical systems (e.g. the heating and cooling systems and the water heater).
Not surprisingly, they found a number of high priority issues particularly related to air leakage and duct leakage. Additionally, they confirmed our suspicions that our 14-year old heating and cooling systems and water heater need replacing due to safety and efficiency issues.
To test for air leakage, Thomas and Herzlieb depressurized the house by using a blower door and drawing air out of the house. This test indicated that approximately 103 percent of our home’s air exchanges with the outside air through leaks and holes in the building envelope every hour. While this level is within the expected range for an older home (0.65-1.50 air changes per hour), Renewal recommended that we improve the air tightness of our home by sealing the air leaks and fixing gaps in the building envelope.
To improve the thermal barrier of the building envelope (e.g. the portion that insulates the inside from the outside), Renewal recommended that we add to the batting insulation we currently have in the attic by spraying or blowing the insulation under the roof decking to achieve a minimum of R-30 insulation. Several years ago, we insulated the crawlspace below our first floor with closed cell spray foam, which improved the temperature of our downstairs floors considerably. Spraying or blowing insulation into the attic can potentially reduce the summer temperature in our attic by 30 percent.
In their inspection of our attic and crawl space, Thomas and Herzlieb also inspected our ducts and tested the ductwork with a duct blaster. The duct blaster pressurizes the ducts to obtain a measure of leakage. The duct leakage for our downstairs system was only 15 percent while the leakage on the upstairs system measured 64 percent. This level is considerably higher than the 20 to 30 percent duct leakage levels typically seen in older homes. Renewal recommended sealing the attic ducts with mastic and repairing the loose, leaky duct connections in order to improve air tightness.
To test for combustion safety, Renewal checked the gas levels using a leakator and found a gas leak in our upstairs fireplace and near the water heater. Upon learning that we rarely use the fireplace, they recommended closing the valve, thereby eliminating the gas leak. The water heater, given its age and condition, failed the combustion safety tests, indicating that exhaust gases are entering the crawlspace. While the level of undiluted carbon monoxide detected (31 parts per million) is not considered dangerous, Thomas recommended replacing the water heater with a high efficiency, power vented system which sends combustion gases directly outside with no chance to mix with indoor air.
Renewal also recommended replacing the upstairs furnace with a high efficiency, sealed-combustion system to prevent back drafting, which causes carbon monoxide and other fumes to enter the house back down the chimney flue. Both furnaces, which are nearing the end of their useful life, should be replaced in the near future.
To help us correct these problems, Renewal provided us with a recommendations and improvement plan that included approximate costs for improving the building efficiency. For example, Renewal estimated that it would cost between $1,300 and $1,500 to insulate and air seal the attic and $1,600 to $1,900 to repair the duct leakage. Renewal recommended that three custom fit storm windows be installed on the three front windows of our first floor for a cost of $450 to $550 per window. Estimates for replacing the water heater and HVAC systems were between $3,000 and $6,000 and $7,500 and $13,000 (per system) respectively. Thus, the total cost of the recommendations amounted to $11,150 to $22,950. There are also many low cost improvements a person can do to solve their home’s problems and the project can be done in stages to help the homeowner budget.
Thomas informed us that we could potentially receive rebates from Georgia Power of up to $550 for the air and duct sealing and attic insulation. Additionally, we can receive a federal tax credit of up to $1500. In the near future, homeowners will also be able to receive rebates from the City of Atlanta through their SHINE program (the Sustainable Home Initiative for a New Economy), if the home is within the city limits. Thomas informed us that we could potentially receive rebates from Georgia Power of up to $550 for the air and duct sealing and attic insulation. Additionally, we can receive a federal tax credit of up
to $1500. In the near future, homeowners will also be able to receive rebates from the City of Atlanta through their SHINE program (the Sustainable Home Initiative for a New Economy), if the home is within
the city limits. Additionally, the cost of the assessment not covered by the Georgia Power rebate is credited towards the cost of improvements, should one decide to use Renewal System Solutions to
implement the recommendations.
While we were aware of some of these problems in our home, we did not realize we had such significant air leakage and gas leaks in our fireplace and crawl space. Given that we have two small children and given that we spend a significant amount of time in our home, I was glad to learn about these issues and plan to correct them in the near future.
While we would like to address all of the diagnosed problems, we are not able to do so all at once, even with the potential rebates and tax credit. The assessment, however, provided us with valuable information and a plan for which home improvements we need to implement over the course of the next several years. We learned a great deal about how to make our home more energy efficient, comfortable and healthy and we highly recommend the process to those looking to do the same.
Assessments usually cost anywhere from $450 to $600 depending on the size of the home and the amount of time it takes to assess the home. The assessment process Renewal uses is similar to EarthCraft and can be used to help certify a home as EarthCraft. Upon completion of the assessment, Renewal System Solutions prepares a report and presents the findings to the homeowners.
For more information about Renewal System Solutions, see www.RenewalSystemSolutions.com or call (404) 378-6962. For more about energy audits, visit www.energystar.gov, click on the Home Improvement tab and look for the Assess Your Home links.