HERS Ratings Reveal How Bad the Good Old Days Were


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Putting in place some fairly run-of-the-mill efficiency improvements can lead to substantial increases in home energy rating scores. That's what Adams Electric Cooperative in western Illinois has learned when it created an energy improvement program for existing housing using energy ratings. The ratings scores suggest the extent of improvement opportunities in older housing outside of the low income restrictions of weatherization.

The Adams Electric program, known as the EnergyWise Grant Assistance Program, serves the three counties of Adams, Brown, and Schuyler. The region includes the picturesque river town of Quincy, IL, with its many Nineteenth Century homes dating to a time when the Mississippi River offered the only commercial thoroughfare for the area. The homes in surrounding farm communities similarly tend to be older.

The key element in the program is a $50 grant for every rating point improvement in an existing house. The homeowner must pay for the home energy rating which usually costs about $350. The ratings must include a blower door test and must be performed by a rater certified by EnergyWise Homes of Illinois, the state's HERS program.

Funding for the EnergyWise Grant Assistance Program came from a $250,000 grant by the Illinois Department of Commerce and Community Affairs (DCCA) through its stripper well petroleum violation funds. Through the grant, DCCA hopes to learn what people value most about ratings at the same time it is helping them save energy and reduce pollution.

EnergyWise Homes of Illinois uses the REM/Rate software as its HERS modeling tools. With the software, the energy rater develops an initial ratings score for the home and then analyzes alternative improvement strategies. The choice of retrofit measures supported by the program is made in consultation with the homeowner. Cory Herren, an in-house rater for Adams Electric and its marketing representative, said that the measures chosen most frequently are furnace upgrades, new windows, and air sealing. The grant payments are not released until the energy measures are installed and verified.

During the late winter and early spring of 2002, the program had completed 74 ratings. With ratings ranging from a low of just 17 and a high of 87, the average initial rating was 53.8. On average, the chosen energy improvements were projected to increase ratings by 23.1 points.

Measure installation, verification, and grant payment has been made on 28 of the 74 ratings. For these completed projects, the average initial rating was 56.9, which is not very different from the average rating for the total group. The installed measures for completed homes raised the ratings an average of 20.8 points.

One might expect any group of homeowners participating in a grant program to draw in some ringers. Was the house with the rating of 17 really liveable? Was the owner of the home that rated at 87 - already Energy Star - just looking to show his personal virtue? If we eliminate the lowest and highest portions of the distribution, we can reduce the influence of these ringers. For instance, we can look at the middle two-thirds of the sample where there are 50 homes. Those 50 homes ranged from a low rating of 40 to a high of 66. The average rating was 54.8 and the average rating point increase from chosen measures was 21.9.

Though one would not expect homeowners with homes they believe to be efficient to select themselves for participation in this type of program, I think it is entirely believable that we would find sizeable numbers of existing homes in America's older communities to rate within the range of 40 to 66 and to have easily identifiable improvement opportunities which would increase those ratings by 20 points. Capturing such opportunities in the older homes of people who do not qualify for the Weatherization Assistance Program - over 3 million in Illinois alone - would be important to meeting the nation's energy independence and pollution prevention goals.


The 1885 Queen Anne style house above has maintained many of the up-scale features of its original construction despite serving for a number of years as a two-family residence.


The inner and outer double-door main entrance to the house above presented a challenge to Larry Long as he conducts a blower door test, but he finds a way.


This 1872 Italianate style home in Quincy had an initial HERS score of 43 with winter space heating bills of $300 to $500 per month. The EnergyWise Grant Assistance Program help the homeowner raise the home's score by 36 points to 79 with a grant of $1800 that partially paid for blown insulation in the walls and attic, tightening the shell, and a new furnace.


For additional information, contact James Cavallo, Ph.D., Principal, at 630 971-2016 or send e-mail to cavallo@Kouba-Cavallo.com.

This page was last updated on July 23, 2002.