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Title: HERS experiment cause for confidence.

Abstract

At last April's Affordable Comfort conference, I conducted a small HERS (home energy ratings) experiment to examine the relative variability of ratings in new and older homes. The experiment grew out of discussions with Oak Ridge National Laboratory Senior Researcher Mark Ternes and EPA Energy Specialist Mia South about how good the HERS tools currently employed in the new homes market are at identifying cost-effective conservation measures in existing homes. Older homes present challenges for raters that may not generally exist in new construction. These include the absence of blueprints, the inability to interview the builder, the difficulty of identifying the operating efficiency of installed equipment, and different envelope characteristics within the home caused by partial remodels over the years. For precisely these reasons, the need for accurate ratings of older homes is acute. The efficacy of ratings in existing homes hinges on two questions: How accurate are the ratings in existing homes? and, How much does accuracy matter to the selection of conservation measures? A small experiment was organized to test the variability of ratings. Two homes were chosen to represent the very broad spectra that raters can find in the new-construction and existing-home housing stock. The new homemore » in Park Ridge, Illinois, is typical in size and layout of the homes being built in the suburbs around Chicago. This four-bedroom, two-story house with finished basement measures slightly more than 4,000 ft{sup 2}, including the basement. The older home is located in Elgin, Illinois, and was built before 1940, probably sometime in the '20s or '30s. This two-bedroom house has a basement in which the furnace, water heater, clothes washer, and dryer are located. The raters disagreed as to whether the basement should be considered part of the conditioned space. Excluding the basement area, the house measurement approximately 1,000 ft{sup 2}. The rating process included a site visit to measure the homes features, inspection of the blueprints for the new home (none existed for the Elgin home), and a blower door test. After the raters completed their analysis, I examined the effect that the variability of ratings for the Elgin home had on choices for energy conservation measures. Although the sample was small, the results of this experiment are valuable. They may be summarized as follows: First, the ratings that different analysts estimated varied more widely for the older home than they did for the new home. Second, for the older home, the identification of cost-effective energy conservation measures was insensitive to the variation in ratings. Clearly, these findings need to be verified in further experiments. But it is noteworthy that the separate ratings of the new home were in such good agreement, and that cost-effective efficiency recommendations can be arrived at even when divergences exist in the absolute rating value. These findings also suggest that it is appropriate to have confidence in ratings as a tool for identifying cost-effective energy measures in older housing stock.« less

Authors:
;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
EE
OSTI Identifier:
942623
Report Number(s):
ANL/ES/JA-33142
Journal ID: ISSN 0896-9442; TRN: US200920%%80
DOE Contract Number:  
DE-AC02-06CH11357
Resource Type:
Journal Article
Journal Name:
Home Energy Mag.
Additional Journal Information:
Journal Volume: 16; Journal Issue: 5 ; Sep./Oct. 1999; Journal ID: ISSN 0896-9442
Country of Publication:
United States
Language:
ENGLISH
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; ENERGY CONSUMPTION; ENERGY CONSERVATION; RESIDENTIAL BUILDINGS; URBAN AREAS

Citation Formats

Cavallo, J. D., and Energy Systems. HERS experiment cause for confidence.. United States: N. p., 1999. Web.
Cavallo, J. D., & Energy Systems. HERS experiment cause for confidence.. United States.
Cavallo, J. D., and Energy Systems. Wed . "HERS experiment cause for confidence.". United States.
@article{osti_942623,
title = {HERS experiment cause for confidence.},
author = {Cavallo, J. D. and Energy Systems},
abstractNote = {At last April's Affordable Comfort conference, I conducted a small HERS (home energy ratings) experiment to examine the relative variability of ratings in new and older homes. The experiment grew out of discussions with Oak Ridge National Laboratory Senior Researcher Mark Ternes and EPA Energy Specialist Mia South about how good the HERS tools currently employed in the new homes market are at identifying cost-effective conservation measures in existing homes. Older homes present challenges for raters that may not generally exist in new construction. These include the absence of blueprints, the inability to interview the builder, the difficulty of identifying the operating efficiency of installed equipment, and different envelope characteristics within the home caused by partial remodels over the years. For precisely these reasons, the need for accurate ratings of older homes is acute. The efficacy of ratings in existing homes hinges on two questions: How accurate are the ratings in existing homes? and, How much does accuracy matter to the selection of conservation measures? A small experiment was organized to test the variability of ratings. Two homes were chosen to represent the very broad spectra that raters can find in the new-construction and existing-home housing stock. The new home in Park Ridge, Illinois, is typical in size and layout of the homes being built in the suburbs around Chicago. This four-bedroom, two-story house with finished basement measures slightly more than 4,000 ft{sup 2}, including the basement. The older home is located in Elgin, Illinois, and was built before 1940, probably sometime in the '20s or '30s. This two-bedroom house has a basement in which the furnace, water heater, clothes washer, and dryer are located. The raters disagreed as to whether the basement should be considered part of the conditioned space. Excluding the basement area, the house measurement approximately 1,000 ft{sup 2}. The rating process included a site visit to measure the homes features, inspection of the blueprints for the new home (none existed for the Elgin home), and a blower door test. After the raters completed their analysis, I examined the effect that the variability of ratings for the Elgin home had on choices for energy conservation measures. Although the sample was small, the results of this experiment are valuable. They may be summarized as follows: First, the ratings that different analysts estimated varied more widely for the older home than they did for the new home. Second, for the older home, the identification of cost-effective energy conservation measures was insensitive to the variation in ratings. Clearly, these findings need to be verified in further experiments. But it is noteworthy that the separate ratings of the new home were in such good agreement, and that cost-effective efficiency recommendations can be arrived at even when divergences exist in the absolute rating value. These findings also suggest that it is appropriate to have confidence in ratings as a tool for identifying cost-effective energy measures in older housing stock.},
doi = {},
journal = {Home Energy Mag.},
issn = {0896-9442},
number = 5 ; Sep./Oct. 1999,
volume = 16,
place = {United States},
year = {1999},
month = {9}
}