Performance Results for Massachusetts and Rhode Island Pilot Community C. Gates and K. Neuhauser Corporation

March 2014

NOTICE

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Performance Results for Massachusetts and Rhode Island Deep Energy Retrofit Pilot Community

Prepared for:

The National Renewable Energy Laboratory

On behalf of the U.S. Department of Energy’s Building America Program

Office of Energy Efficiency and Renewable Energy

15013 Denver West Parkway

Golden, CO 80401

NREL Contract No. DE-AC36-08GO28308

Prepared by:

C. Gates and K. Neuhauser Building Science Corporation 30 Forest Street Somerville, MA 02143

NREL Technical Monitor: Cheryn Metzger Prepared under Subcontract No. KNDJ-0-40337-03

March 2014

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Contents

List of Figures ...... vi List of Tables ...... vii Definitions ...... viii Executive Summary ...... ix 1 Introduction ...... 1 2 Background ...... 3 2.1 New Construction, Retrofits, and DERs ...... 3 2.2 Previous Work ...... 4 2.3 Building Science Corporation and the National Grid DER Pilot Program ...... 5 3 National Grid Deep Energy Retrofit Pilot Program ...... 6 3.1 Measures and Targets ...... 6 3.2 The Community of Retrofits ...... 8 4 Energy Use Results and Analysis...... 18 4.1 Reduction Versus Performance Achieved ...... 18 4.2 Site and Source Energy ...... 19 4.3 On-Site Generation ...... 19 4.4 Energy Use Data ...... 19 4.4.1 Energy Use Data Normalization and Disaggregation ...... 25 4.5 Characterization of Post-Retrofit Energy Use ...... 29 4.5.1 Pre- and Post-Retrofit Energy Use Comparison ...... 29 4.5.2 Post-Retrofit Energy Use per Household ...... 36 4.5.3 Post-Retrofit Energy Use Intensity ...... 41 4.6 Impact of Retrofit Package Variations ...... 46 4.6.1 Heating Fuel Source ...... 46 4.6.2 Included Versus Excluded Basement ...... 47 4.6.3 Unvented Versus Vented Attic ...... 50 4.6.4 Airtightness Versus Post-Retrofit Energy Use ...... 52 4.7 Conclusions of Energy Use Analysis ...... 53 5 Airtightness Results and Analysis ...... 55 5.1 Airtightness Test Results ...... 58 5.2 Analysis of Airtightness and DER Package Variations ...... 62 5.2.1 Inclusion/Exclusion of Basement in Air Control Enclosure ...... 62 5.2.2