Lightweight steel-framed (LSF) structural elements in building construction provide a way
of increasing building sustainability. These structural elements present great potential
for recycling and reuse, allowing the conservation of natural resources and the
environment. When compared with other materials, these construction components also
provide other advantages: reduced weight with simultaneous high mechanical strength;
easier prefabrication, allowing modular elements and higher quality control; shorter
periods for assembling the building on-site; no dimensional variations caused by moisture;
and low cost. The high thermal conductivity of steel could be a drawback, leading to
thermal bridges if not well designed and executed. In the case of LSF components (e.g.
walls and slabs) it is necessary to take special care with the elements’ design
optimisation, with it being essential to use continuous thermal insulation. The building
envelope thermal performance is crucial to provide good thermal behaviour and energy
efficiency, allowing a reduction of operational energy. In this paper, the LSF
construction system is analysed in order to show its main advantages and drawbacks. The
assessment of embodied and operational energy is essential to perform a life cycle
analysis. The reduction of both energies’ consumption is crucial to increase the
sustainability label. Special focus will be given to the mitigation strategies of
operational energy in LSF construction.