Perforated Steel Stud to Improve the Acoustic Insulation of Drywall Partitions

Steel studs are an inevitable part of drywall construction as they are lightweight and offer the required structural stability. However, the studs act as sound bridges between the plasterboards, reducing the overall sound insulation of the wall. Overcoming this often calls for wider cavity walls and complex stud decoupling fixtures that increase the installation cost while reducing the floor area. As an alternative approach, this research reveals the potential of perforated studs to improve the acoustic insulation of drywall partitions. The acoustic and structural performance is characterized using a validated finite element model that acted as a prediction tool in reducing the number of physical tests required. The results established that an acoustic numerical model featuring fluid-structure-interaction can predict the weighted sound reduction index of a stud wall assembly at an accuracy of ±1 dB. The model was used to analyze six perforated stud designs and found them to outperform the sound insulation of non-perforated drywall partitions by reducing the sound bridging. Overall, the best performing perforated stud design was found to offer improvements in acoustic insulation of up to 4 dB, while being structurally compliant.

Perforated Steel Stud to Improve the Acoustic Insulation of Drywall Partitions

Steels studs are an inevitable part of drywall construction as they are lightweight and offer the required structural stability. However, the studs act as sound bridges between the plasterboards reducing the overall sound insulation of the wall. Overcoming this often calls for wider cavity walls and complex stud decoupling fixtures that increase the installation cost while reducing the floor area. As an alternative approach, this research reveals the potential of perforated studs to improve the acoustic insulation of drywall partitions. The acoustic and structural performance is characterized using a validated finite element model that acted as a prediction tool in reducing the number of physical tests required. The results established that an acoustic numerical model featuring fluid-structure-interaction can predict the weighted sound reduction index of a stud wall assembly at an accuracy of ±1 dB. The model was used to analyze six perforated stud designs and found to outperform the sound insulation of non-perforated drywall partitions by reducing the sound bridging. Overall, the best performing perforated stud design was found to offer improvements in acoustic insulation of up to 4 dB, while being structurally compliant.

Parameter analysis and modification of transmission loss models for multi-layered cavity walls

Multi-layer cavity wall (MCW) systems, which refer to each panel in the structure being made up of two or more layers of lightweight board, have become more widely used. However, unlike the detailed approaches that were available for predicting single-layer cavity walls (SCW), few studies have addressed the MCW involving different layers attached together. In this research, we applied two theoretical models of SCW, analyzed the key parameters and modify to have appropriate application for MCW. The predictive capability of the models was then evaluated by comparing them with results of experiment and commercial software. The results showed that Sharp’s model was suggested only when the thickness of the steel stud of about 0.75 mm. Through modifying the input values of the compliance of steel ( CM), attenuation factor ( F) and the limiting angle of incident (θ L) in Davy’s model, and the prediction of the proposed model showed great consistent with experiments.

Thermal evaluation of a highly insulated steel stud wall with vacuum insulation panels using a guarded hot box apparatus

This paper presents the results of a Guarded Hot Box (GHB) experiment on a wall assembly made up of both steel stud framing and an external insulating assembly which incorporates vacuum insulation panels (VIPs) for which knowledge of the composition of the VIP barrier foil is not readily available. The purpose of the tests is to provide an experiment result for thermal resistance of a wall assembly containing several sources of thermal bridging, including those due to the barrier foil at the edge of and joint material between the VIPs and the condensation potential on the interior surface due to the steel studs. The steady-state GHB experiments were completed in accordance with ASTM C1363 for an interior air temperature of 20.9°C and an exterior air temperature of −34.9°C; this resulted in a thermal resistance for the wall assembly of 6.8 ± 0.8 m2 K/W. Surface temperature measurements on a VIP in the wall assembly indicated that increased levels of heat transfer were occurring at the edges of the VIPs as compared to the center of the panel confirming thermal bridges were present at the panel edge. Measurement of the temperature on the interior surface of the sheathing board around the steel stud indicated that the external insulation effectively minimized the risk of condensation due to the steel studs. Determining the thermal resistance and condensation risk for a wall assembly which contains VIPs for which knowledge of the barrier film is not readily available demonstrates the potential for use of such a wall assembly according to energy and building code requirements. The wall assembly and test details can also be used to compare industry standard calculation methods and detailed 2D and 3D simulations to the GHB test result. The comparison can be used to inform on the validity of using calculations and simulation methods in lieu of testing for energy and building code compliance. The comparison of calculations and simulations is not the scope of the work presented in this paper and will be explored in future publications.

Analysis of the transmission loss of double-leaf panels with an equivalent spring–mass model for studs

The purpose of this study was to investigate the sound insulation of double-leaf panels. In practice, double-leaf panels require a stud between two surface panels. To simplify the analysis, a stud was modeled as a spring and mass. Studies have indicated that the stiffness of the equivalent spring is not a constant and varies with the frequency of sound. Therefore, a frequency-dependent stiffness curve was used to model the effect of the stud to analyze the sound insulation of a double-leaf panel. First, the sound transmission loss of a panel reported by Halliwell was used to fit the results of this study to determine the stiffness of the distribution curve. With this stiffness distribution of steel stud, some previous proposed panels are also analyzed and are compared to the experimental results in the literature. The agreement is good. Finally, the effects of parameters, such as the thickness and density of the panel, thickness of the stud and spacing of the stud, on the sound insulation of double-leaf panels were analyzed.