Steel’s popularity as a structural element is rising, and there’s scope for more use of prefabrication. These are two of the trends BRANZ has identified for commercial building construction.
BRANZ RECENTLY GAINED some insights into commercial building trends by analysing Statistics New Zealand consent data on building types over an 8-year period.
Commercial buildings are defined as hotels, motels, shops, restaurants, taverns, offices and administration buildings.
The value of new commercial consents has tracked total non-residential buildings consents over the period.
Value hit by financial crisis
While most value has been for offices and administration buildings, over the last 4 years, the values of consents for shops, restaurants and taverns have been almost equal (see Figure 1).
Meanwhile, hotels and other short-term accommodation has had only a small share of the total value of new commercial consents, particularly since 2009.
The value of new shop, restaurant and tavern consents has remained relatively steady over the 8 years. While there was a slight dip in 2008/09 due to the impacts of the global financial crisis, by 2010, the value of consents was increasing again.
New offices and administration buildings were trending upwards between 2006 and 2009. However, the value of these new buildings dropped sharply in 2010.
Metal wall claddings on the rise
Concrete, particularly panels, has been the dominant wall cladding material in commercial buildings. However, steel, aluminium and other metal have been trending upwards since 2010 (see Figure 2).
Concrete is much more common in multistorey commercial buildings than single-storey, and its share is indicative of the number of single-storey versus multi-storey buildings.
Roofs have typically been clad in sheet metal. Sheet metal’s share has been increasing since 2011 and is currently sitting just under 100%.
Steel and concrete frames similar
Steel frames have been the most common since 2009. However, concrete frames have been trending upwards since 2011, and in 2013, their share was almost the same as steel’s.
Timber frames are uncommon in commercial buildings (see Figure 3).
Prefabrication’s share could grow
Prefabrication work is currently estimated at about 7% of the total construction value of commercial buildings, based on BRANZ materials surveys.
This covers prefabricated frames, precast wall panels, precast floor beams and slabs, and prefabricated timber and steel roof trusses. It excludes windows, partitions, services and joinery, much of which is manufactured off site and arguably could be considered to be prefabrication.
It is estimated that, with maximum uptake of the excluded components added in, the prefabrication content has a potential share of 28% of new commercial building work.
This means there is considerable scope for further uptake of prefabrication in commercial buildings.
Articles are correct at the time of publication but may have since become outdated.