23 September 2011
This paper describes the field performance of space conditioning and water
heating equipment in four single-family residential structures with advanced thermal
envelopes. Each structure features a different, advanced thermal envelope design: structural
insulated panel (SIP); optimum value framing (OVF); insulation with embedded phase
change materials (PCM) for thermal storage; and exterior insulation finish system (EIFS).
Three of the homes feature ground-source heat pumps (GSHPs) for space conditioning and
water heating while the fourth has a two-capacity air-source heat pump (ASHP) and a heat
pump water heater (HPWH). Two of the GCHP-equipped homes feature horizontal ground
heat exchange (GHX) loops that utillize the existing foundation and utility service trenches
while the third features a vertical borehole with vertical u-tube GHX. All of the houses were
operated under the same simulated occupancy conditions. Operational data on the house
HVAC/Water heating (WH) systems are presented and factors influencing overall
performance are summarized.