Historical Structural Steelwork


The refurbishment or ‘adaptive re-use’ of existing buildings currently forms a significant part of the workload for many architects and engineers.  The structural engineer will be required to make an appraisal of the existing steelwork in these buildings.  This article provides sources of information for identifying the properties and making an assessment of the historical structural steelwork.


Steel section sizes, dimensions and properties

Up until the mid-1960s a lot of structural steel used in New Zealand was sourced from the United Kingdom (UK) while a small amount of structural steelwork was sourced from United States of America (USA). For steel from the UK a very useful publication is the Historical Structural Steelwork Handbook (Bates, 1984). This publication is available to view here and contains numerous extremely useful tables for properties of steel beams and other sections dating from 1972 back to 1887.


Typical pre-1976 steel building systems used in New Zealand

Use of iron and steel in existing buildings
A good summary of the use of iron and steel in structures from 1780 to the present day is given in (Bussell, 1997). For a New Zealand context the relevant period is from 1900. Existing New Zealand building with ferrous material will mostly be steel. This was the preferred material for structural members in buildings from 1880 onwards. The exception is columns, especially gravity columns functioning as vertical props for the floor. Cast iron was used for these through to just after 1900 and cast iron columns are found in some of the oldest New Zealand buildings (NZSEE, 2006).  They are typically “chunky” with thick sections, often ornate or complex profile fluted or plain hollow circular or cruciform columns. Their surface is typically pitted with small blowholes…..(full article available here).