Full Description

Improvements in the energy efficiency of buildings, based on building enclosure design, are commonly achieved with increased thermal insulation. Most model codes use thermal insulation as the main method of improving energy efficiency. Thermal resistance is a steady state property and is readily understood by building designers and the like. However, there is a significant body of work that indicates that thermal mass could also offer a means to both improve occupant comfort and lower energy use. Thermal mass affects the dynamic flow of heat but has not received as much attention as thermal resistance for the purposes of developing building codes for improving energy efficiency. Moreover, many prior studies of thermal mass have been focused on walls and have been qualitative in their descriptions of thermal mass. This study has focused on low-slope roofing based on steel and concrete decks. The effects of increased thermal resistance, increased concrete thickness, concrete density, and the use of commercially available roofing boards have been evaluated in terms of dynamic thermal properties. The data provided could be used by building designers to make construction choices to improve energy efficiency and thermal comfort. The results show that the benefits of increasing thermal resistance are diminished at todays code required levels. However, the addition of thermal mass by using concrete decks significantly affects the dynamic thermal properties. While concrete decks do not significantly reduce heat flux, they have very significant effects on the time shift periodic thermal transmittance and areal heat capacities. Also, even though added thermal mass may not provide a large benefit for building owners in terms of energy efficiency, aggregated it could be significant for grid operators and utilities.

Product Details

Published: 2022 Number of Pages: 10 Units of Measure: Dual Product Code(s): DBldgsXV-C001