Measured Differences Of Ground And Space Temperatures For Side-By-Side Slab-On-Grade Residences With And Without Carpet

A particularly suspect aspect for building simulations has been the ability to predict ground heat transfer. In Florida, slab-on-grade construction dominates. To better understand ground heat transfer, as well as the differences between uncovered slab and applying an insulation layer (carpeting) over a slab in a mild climate, the Florida Solar Energy Center built two identical residential laboratory buildings with 164 embedded slab and ground thermocouples. In July 2014, an experiment began comparing the thermal performance of carpet to uncovered slab flooring. The buildings were cooled to 77°F (25°C) in summer and heated to 73°F (22.8°C) in winter. The thermostats were set to either cooling or heating, as during Florida’s winters interior temperatures sometimes drift above the cooling set point and occasionally when set to cooling they drift below the winter set point. Each laboratory home is unoccupied with automated internal sensible and moisture loads provided hourly to represent human, appliance, and lighting loads. The hypothesis is that in Central Florida, where year-round ground temperatures are between winter and summer set points, the non-carpeted slab should have an advantage. The paper presents findings for a year’s worth of data collection, differences in heating and cooling loads on each home, and images of temperature differences through the matrix of slab measurements. Net heat transfer in Central Florida was small during the cooling season. There was some benefit available during early spring time. Results are sensitive to geographic location and interior set point