Numerical Investigation of Effects of Camlock System on Thermal Conductivity of Structural Insulated Panels

Abstract

Structural insulated panels (SIPs) are widely used in residential and commercial buildings due to their reliable mechanical and thermal performance. However, using framing members and nails to join SIPs causes thermal bridging across the insulation and thus increases heat losses from the building envelope. Alternatively, SIPs joined with embedded camlock systems can overcome this issue. In this paper, a parametric study of the effects of the camlock system material and SIP geometric design on the thermal performance of SIP walls was investigated using a multi-scale finite element modeling approach. The model considers the structural design details of the camlock system. In addition, the effects of the SIP materials, SIP thickness, and the number of camlock systems per unit area on the through-thickness thermal conductivity of the SIP walls are examined. It was found that the SIP thickness is a dominating factor influencing the thermal performance of the SIP. The through-thickness (overall) thermal conductivity of the SIP wall increases linearly with the increase in the number of camlock systems used per unit area. However, it rises exponentially with the increasing SIP thickness. The reduction in the overall R-value of the SIP caused by the camlock system embedded in the SIP did not exceed 13.8%.