Robert Clarke of Fusion Building Systems tells us about Modern Light Gauge Steel as a framing system.
Modern Light Gauge Steel (LGS) building systems have Fabric First in their DNA! This is because steel is such an excellent conductor of heat and therefore all LGS systems have had no option, other than to tackle cold bridging. This was the case well before current Building Regulations made control of thermal bridging an important issue for all construction methods. In effect, LGS has been training at altitude as regards thermal bridging and solutions are second nature.
In order to keep the frame warm and tackle cold bridging, all LGS systems place insulation outside of the steel stud. The amount of insulation outside the stud is designed to achieve the desired U-value and to avoid the risk of interstitial condensation. There are a variety of means of achieving a warm frame, ranging from site applied rigid insulation boards, to factory injected systems.
But having a warm frame, with excellent U and Psi values, plus good air-tightness is no longer enough. A true, Fabric First approach requires collaboration.