Steel benefits from exposure
The attractions of exposing constructional steelwork seem to be growing, as we have been noticing in the increasing number of projects making a virtue of its aesthetic qualities, both internally and externally.
Exposed steelwork has long been familiar in shopping malls and airport terminals for example where their slenderness and lightness are appreciated by building users. Exposed bracing is a familiar feature on well-known major buildings like Cannon Place, Heron Tower and Broadgate Tower in London.
Supporting the architects in their drive to express their vision is a supply chain including structural engineers, steelwork contractors and steel manufacturers. Weathering steel and strong tubular sections are in demand particularly for external use.
Often the exposed steel decision has been taken to acknowledge the heritage of the locality; so we see exposed steelwork in former industrial areas. Weathering steel is increasingly selected for external use in these and other areas, again for aesthetic reasons. The gradually acquired patina has become a feature in its own right on many iconic local landmarks. Architect designed houses are being built for discerning clients attracted to the weathering qualities of exposed steelwork.
Engineering support has been provided by the BCSA and its members in overcoming concerns about issues like thermal movement of exposed steelwork, the impact of penetrations being made unavoidably through the building envelope, the quality of paint finishes, important for conventional steelwork whether it is exposed internally or externally, fire protection of structural sections which might otherwise have been protected by boarding, and fabrication stamping and marking on the steel.
These issues have obviously all been overcome, hence the growing presence of exposed steelwork, and expressed structures, nationally. Several examples in this issue of NSC show some projects that are taking advantage of exposed steelwork while other examples can be seen on structures of all types up and down the UK.
In this issue we see exposed steelwork at a building in the heart of London’s creative and technology industries in Hoxton, a key element of a refurbishment project that gives new life to an existing building previously used as offices and to house a printworks. The internal fabric of the building will be exposed, providing the internal ‘feel’ and ambience that tenants in that part of London appreciate, as well as acknowledging its industrial heritage.
Exposed steelwork, whether weathering steel or painted steel, also blends pleasingly with other buildings in heritage areas. A stone’s throw from Hoxton, in another City fringes area, Shoreditch, we reported in our March issue on One Crown Place where exposed steelwork features alongside a retained facade on a mixed use and residential project where parts of the 15 trusses supporting twin residential towers will be exposed as architectural highlights.
It is encouraging that such a wide range of building owners and users appreciate the virtues of exposed steelwork; steel construction’s other virtues will have become apparent during the construction process of course, both to clients and construction teams.