Information Papers

Steel Component Design for Deconstruction

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Summary

This information paper addresses the issues that designers need to consider in order to facilitate easier building deconstruction, particularly of structural steel

The construction industry must rethink how buildings are put together to maximize the usefulness and value of components at the end of their life and to make best use of the resources generated by demolition. Strategies are required to minimize the materials that will end up in landfills. The ease with which components can be recovered from a building is greatly affected by how the building was put together in the first place. Therefore, thought about final obsolescence and how the environmental and financial value of a building can be maximised at the end of its useful life is needed at the design stage.

Ease of deconstruction is affected by the building systems and technologies used, and availability of relevant documentation and information. Appropriate use of technologies and their successful integration into the design process will facilitate an increased reuse of structural steel components. Key principles to design for deconstruction in steel include:

using durable components that can be reused after removal;
considering the actual process of deconstruction at the design stage and providing a deconstruction plan for the building;
considering a building as a series of layers related to different life-spans of components;
ensuring that individual components can be readily removed when necessary and maintained or replaced;
using simple structural grids with clear support lines;
limiting the number of parts, number of tasks, number of tools, and the time or degree of difficulty of the deconstruction tasks to reduce cost and time involved;
where possible using prefabricated components that are assembled on site and can be disassembled for reuse/recycling;
considering connections that can be reversed and avoiding irreversible processes; reversible mechanical fixings such as bolts can usually be removed, welding cannot;
where possible using dry construction processes, which are more readily dismantled than wet construction processes;
integrating services with care so that they can be easily identified, maintained, upgraded and replaced;
providing sufficient space and capacity to accommodate machinery needed for dismantling;
ensuring that accurate as-built drawings and records of all changes over the life of the building are kept in a building log book.

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