September 2, 2021
Report

Remote Home Energy Score Assessments, A Feasibility Study

Abstract

Earth Advantage conducted 26 remote sessions on homes located in 11 cities in New York and Oregon (Table 3). These remote assessments were completed within three different HES partnerships and included homes located in urban, suburban, and more rural locations within climate zones 4, 5, and 6. (Table 2). The homes evaluated represented a wide variety of home configurations and characteristics (Table 4 and 5). The majority of remote sessions, utilizing four video conferencing applications (Table 9), had some level of video or audio quality disruptions. These disruptions were only temporary and did not impact the ability to complete the remote assessment. While most of the remote sessions were conducted with the homeowner, a small percentage were conducted with a renter. The renters generally did not have as much knowledge about the home, which made getting accurate info more difficult. Earth Advantage tested two types of remote audits. One being fully remote where all data was collected through the video session and the other being a hybrid approach where a short visit to the property was needed to get exterior measurements. The majority of sessions were conducted fully remotely and in two cases a hybrid approach was used as part of the test (Table 14). The range of time for conducting a remote session was between 1 to 1.5 hours. It is estimated that providing a remote assessment option could reduce time and cost for the assessor and program administrators by 35%, primarily due to reductions in drive times (Table 15). To measure the accuracy of the remote assessment approach, 25 of the homes also had an official onsite assessment conducted by a separate authorized HES assessor. For analysis, the onsite data was compared with the remote data. On average there was a 1 point score difference between the remote and onsite score, with an average score basis MBTU difference of 13% (Table 6 and Chart 2). The study found that 50% of the scores showed no difference in the HES score and 81% of homes were within a one-point difference (Chart 1). The study also found that 44% of the reports showed no difference in the cost-effective upgrades and 88% of reports only showed a one recommendation difference (Chart 3). The home assets that recorded significant differences (>10%) between the remote and onsite assessment were: Attic Area, Window Area, Wall R Value, Cathedral Attic R Value, Window Types, and Duct Location (Table 7). The remote assessment does have its limitations. Overly complex homes were found to be a challenge to assess remotely and they rely heavily on the homeowner’s knowledge of the home or any available documentation. Some homes have complex designs with significant angles, numerous attics or foundations, cathedral attic areas, high levels of window glazing, multiple systems or other variables that can be difficult to assess during a remote session. The remote assessment is reliant on the homeowner’s participation in the remote session and information that is provided to the remote assessor. There can be limitations related to the onsite individual’s knowledge about the home. There may be a variety of scenarios where an impediment could impact the remote assessment or the ability for the homeowner to conduct the session. The study did encounter a few impediments that impacted the ability to conduct the remote sessions, but solutions were found in all of those cases (Table 13). Homeowners that participated in the study were pleased with the process and expressed support for a remote assessment option.

Published: September 2, 2021

Citation

Elton J., M. Winchel, A. Roy, W. Millard, C.A. Holly, and E. Louie. 2021. Remote Home Energy Score Assessments, A Feasibility Study Richland, WA: Pacific Northwest National Laboratory.