Design - Embodied Energy
SBS systems fully optimize the use of steel from a tonnage perspective, and can use as much as 30% less steel than a similar building constructed using hot-rolled sections, open-web steel joists and steel decking. The entire project is designed for disassembly to ensure products used could be reclaimed in the future, or substituted for reclaimed materials in the current design. When using steel as a material, this should be a primary design goal to be able to significantly reduce embodied energy. The following design techniques unique to the SBS system were employed to optimize material use, reduce recurring embodied energy and facilitate the transition from "construction/demolition" or cradle-to-grave ethos to a "assembly/disassembly" or cradle-to-cradle ethos. The focus of re-use centred around the high-embodied energy aspects of a building, namely envelope, finishes and structure.
SBS systems fully optimize the use of steel from a tonnage perspective, and can use as much as 30% less steel than a similar building constructed using hot-rolled sections, open-web steel joists and steel decking.
- Interior partitions are demountable. Because retailers often change branding and retailing strategies, or new retailers move into old retail spaces, churn rates due to renovation are high. Demountable partitions can significantly reduce recurring embodied energy by limiting the use of new materials, construction and demolition over the lifecycle of a retail building.
- Finishes were reduced by leaving the concrete slab exposed. This also exposes the slab such that it can function as a thermal mass; if covered, the effectiveness of this passive strategy can be reduced. The use of SIP panels means that a finish is not needed on the exterior envelope as a paintable smooth steel surface is presented on both the exterior and interior. A light coloured paint, also useful for increasing brightness and daylight penetration, is a neutral finish that does not have to be changed and can suit more retailers.
- A 1-in-12 slope was maintained on the roof. This allows a SIP panel to be bolted down, and thus be demountable, as opposed to a built up roof assembly, which requires demolition and more materials that can increase the amount of embodied energy.
- SIP panels on the walls function the same was as the roof panels and are demountable. The designers reduced the number of panel sizes to 2 to reduce the number of variations and also increase the chance of re-use.
- Structure is bolt-together to ensure it is demountable in its current form and does not need to be cut to be removed.
- The "kit-of-parts" nature of Steel Building Systems makes the use of reclaimed materials and the ability to deconstruct very easy and can facilitate a closed-loop material cycle where SBS manufacturers participate in both assembly and disassembly. This is a similar model that is gaining popularity with furniture and carpet manufacturers. The creative use of standard sizes and components still allow designer creativity through infinite variations of standard products. The carbon neutral SBS building, if all components were reclaimed instead of simply recycled, could have an extremely low embodied energy compared to other structural and envelope materials.