This small home, originally built in 1965, was recently remodeled and received several additional energy-efficiency improvements provided by Hilltop Alliance and Energy Efficiency Empowerment (E3) through a PHARE (Pennsylvania Housing Affordability and Rehabilitation Enhancement) grant.
Hilltop Alliance’s rehabilitation included upgrading to triple-pane windows and replacing the electric furnace with a ductless heat pump system. The existing ductwork serving the electric furnace was removed from beneath the floor, allowing for more complete floor insulation. The home already had a layer of exterior rigid insulation, which was preserved. Floor insulation was upgraded using rigid foam with sealed joints and R-19 fiberglass batts. E3 staff also helped improve the home’s airtightness and ensure the insulation was installed to a high standard.
As part of our work, E3 uses tools developed by the Northeast Energy Efficiency Partnerships (NEEP) to support our evaluations and analysis. We compare the HVAC contractor’s equipment selection with the predicted heating and cooling loads calculated using industry-standard methods, such as ACCA Manual J.
Based on the original design heating load of 20,000 BTU/h, the installed BZ33_HP364Z2 (3-ton) outdoor unit provides approximately 138% of the home’s design heating load. Our analysis suggests that a BZ33_HP273Z2 (2.5-ton) outdoor unit may have provided a closer match, delivering approximately 105% of the design heating load.
Following the rehabilitation, the home is projected to reduce energy use by 68% compared with its pre-rehabilitation condition. E3 contributed to these savings by funding the installation of a 3.5 kW solar photovoltaic (PV) system. Annual utility bill savings are estimated at approximately $800, while E3’s total investment in the project was $19,580.
The home’s Home Energy Score improved from 4 to 10, the highest possible rating.
Congratulations to Hilltop Alliance and everyone involved in making this project a success!
A few illustrations of the details at this Allentown project:
