Phase Change Material-Enhanced Insulation for Residential Exterior Wall Retrofits
Enhancing conventional low cost blown-in insulation with phase change material (PCM) and aerosealing of the wall cavities
Project is on track. The Market Characterization of Advanced Insulation Products for Single- and Multi-family Residences report was completed on August 2021. Monitoring equipment was installed in the demonstration sites and project team has started collecting baseline energy use data. Project team is conducting small-scale laboratory tests of the aerosol wall cavity sealing apparatus and phase-change material.
This project develops and tests a PCM-enhanced insulation solution for existing homes that have little or no wall insulation, with the goal of showing sufficient cost savings and other benefits to recover the cost within 10 years when compared to existing uninsulated walls. Through modeling and selected laboratory testing, the most cost-effective applications of PCMs for wall retrofit-wall assembly in a range of California climate zones will be identified. This will include analyzing PCMs melting point, amount, and installation location (mixed blown-in insulation or applied to the interior wall surface. The project also tests and evaluates the process for aerosol sealing wall cavities in retrofit applications prior to installing cellulose or fiberglass insulation. Finally, the project will evaluate an optimized PCM-enhanced insulation solution for homes in three climate zones (Bay Area coastal (CZ3), Central Valley (CZ12), and Southern California coastal (CZ9)).
It is estimated that the PCM-enhanced insulation could save 5.0 billion therms of natural gas over the next 30 years due to reduce heating loads.This will reduce utility bills for ratepayers while also improving thermal comfort in their home. The timeframe of 30 years for energy saving was determined by the expected durability of the PCM insulation system. PCM is expected to have a lifetime similar to, or longer, than blown-in fiberglass or cellulose ins
It is estimated that the PCM-enhanced insulation could reduce emission by 30 million metric tons of CO2eq emissions as well as reduce criteria pollutant emissions through reduction in natural gas and electricity usage for heating and cooling over the next 30 years.
Key Project Members
TRC Engineers, Inc.
Western Cooling Efficiency Center - UC Davis
Department of Mechanical and Aerospace Engineering - UC Davis