Construction Productivity Trends for Building, Engineering and Construction Services

 Australian Construction Productivity at the Industry Level

 

 

The rate of growth of productivity in the construction industry in a number of countries has lagged that of other industries for at least five decades, and the earliest studies that identified this problem date from the late 1960s. Two explanations for the lack of demonstrable improvement in construction productivity are possible. The first is the importance of measurement, data and issues about the structure and use of price indices for estimating real output (i.e. adjusted for inflation). 

 

The second is the nature of the product and the methods used in delivering and managing the processes involved.  Construction is a labour intensive industry in comparison with manufacturing, but there has been a significant increase in the prefabricated component of construction, which could have been expected to lead to productivity growth. Also, construction methods have become more capital intensive as machinery has got heavier, and the number of cranes, powered hand tools and other equipment used has increased.  However the productivity growth that one would expect to observe as a result of these trends has not occurred, according to measurements by national statistical agencies.

 

Productivity estimates require both a measure of labour inputs, such as hours worked or people employed, and a measure of output, called Industry value added (IVA, the difference between total revenue and total costs). IVA is then adjusted for changes in prices of materials and labour to estimate Gross value added (GVA) using price indexes that assume there has been no change in the quality of buildings. Another problem is the application of a single deflator to the diverse range of buildings and structures. This inability to capture functional differences and quality changes in buildings and structures has adversely affected the measurement of productivity, if construction value added is underestimated due to the deflators used, construction productivity has also been understated.

 

This post compares the deflated GVA per person employed to the IVA per person employed for Building, Engineering and Construction services (the trades), and Total construction. The GVA data comes from the ABS National Accounts (chain volume measures of economic activity). The IVA data and number of people employed in June each year comes from ABS Australian Industry. 

 

 

A Proxy for Construction Productivity

 

In Figure 1 industry output is in constant dollars (the deflated value adjusted for price changes). GVA is the quantity of output produced in a year. The employment data includes all workers but not whether they are full or part-time, or hours worked. 

 

Figure 1. Construction Productivity by Industry

Source: ABS, CER

 

As a measure of productivity GVA per person employed is very approximate, typically the number of hours worked would be used for employment and June may not be a representative month for employment in many industries. Nevertheless, this graph looks familiar, with flatlining growth in Total construction productivity over the period, despite a few bumps along the way. It appears to be a useful productivity proxy. 

 

Using the same data, GVA per person employed can be found for Building, Engineering and Construction services. Here a slight decline in Building has been offset by a small rise in Construction services output per person, with the effects of the pandemic on both apparent in the decline over 2020-21. Building construction may have been affected by a shift from commercial to an increased share of residential in the output mix and more high rise work. Because Construction services are generally labour intensive they will have a lower value of output per person, but this data shows there was increase in this measure of productivity between 2007 and 2021 and Construction services was the only one of the three industries to register a gain on this measure. 

 

Engineering construction activity took off in the mining boom from 2010, and output per person has followed the rise and fall in work done since and, although below the peak years of 2012-14, it now reflects the large volume of infrastructure work in transport and energy. Since 2011 GVA per person in Engineering has been much higher than Building construction, nearly twice as much in some years, and Construction services, nearly three times as much in some years. 

 

These differences in output per person employed reflect differences in capital requirements and expenditure on purchases of buildings, structures, software, equipment and machinery (known as gross fixed capital formation or GFCF). The higher the capital requirements, or capital intensity, of an industry the higher the level of output per person employed is expected to be, because workers with more capital are more productive. Both excavators and shovels require one operator but the former shifts more soil.

 

 

Current Dollar Industry Comparison 

 

The chain volume measure of GVA per person employed can be compared to the original, unadjusted current dollar Industry value added (IVA) per person employed. Again, this is an indicative but imprecise proxy for construction productivity. In Figure 2 there is a clear upward trend in all three industries, with increasing nominal value of output as prices rise faster than the number of people employed. 

 

The growth in IVA per employee for Building is the greatest contrast to the GVA data. Here, Building has had a sustained increase since 2012 compared to the flat, no growth trend in GVA per employee. This suggests there has been a better productivity performance by building contractors than the one recorded in official statistics. 

 

Engineering has a similar pattern in both GVA and IVA graphs, with a sharp rise in output per employee after 2010 that flattened out after 2016 at around 50 per cent higher than the pre-mining boom level. This has been a significant increase in productivity. Both Building and Engineering typically have larger firms than found in Construction services, which has lagged the other two industries in growth in IVA per employee. 

 

Without deflation the value of output could be expected to rise somewhere around the rate of CPI inflation, which totalled 35.8 per cent and averaged 2.2 per cent a year between 2007 and 2021. Over that period Building IVA increased by 120 per cent, Engineering IVA by 117 per cent, and Construction services by 50 per cent. More significantly, IVA per person employed for Building increased by 61.6 per cent, for Engineering by 57.3 per cent, but for Construction services only 27.7 percent, suggesting that is where the productivity ‘problem’ lies. However, the IVA and GVA figures are contradictory, with the latter showing better performance. 

 

 

Figure 2. Nominal output per employee

Source: ABS, CER

 

IVA per employee again highlights differences in the capital requirements of industries. In the long run, investment in GFCF determines industry growth rates and their level of labour productivity. Labour intensive industries like Construction services have a low level of IVA per person employed, but also have lower capital requirements. Engineering has always been more capital intensive than Building, but the gap seems to have closed with the increase in residential high-rise activity after 2016. 

 

Conclusion

 

Construction productivity estimates are usually given for Total construction, and typically show little or no growth over many decades. However, Total construction is measure of the combined performance of three different industries: Building, Engineering and Construction services. This post compared the deflated GVA per person employed to the nominal IVA per person employed for Building, Engineering and Construction services (the trades), and Total construction.

 

The deflated GVA per person employed data is a proxy for productivity because the value of output is adjusted for price changes, As a combination of deflated output and employment GVA per person employed looks like a measure of productivity, but while it is indicative that is not really the case. Although similar to the output and input data needed to calculate productivity, indexes of output and input are used for productivity analysis, not the original data, and hours worked not numbers employed used. 

 

When the mostly flat chain volume measures of GVA per person employed are compared to the current dollar IVA per person employed there is a clear upward trend in IVA all three industries, with increasing nominal value of output as prices rise faster than the number of people employed. IVA per person in Building and Engineering has increased at nearly twice the rate of CPI inflation, but Construction services by less since 2007. 

 

Construction services IVA per person employed grew significantly less than Building and Engineering. However, the GVA per person employed performance was much better, the only one of the three industries to register a gain on this measure. Construction services have a large impact on productivity because they account for 60 per cent or more of Construction output. 

 

The usefulness of both GVA and IVA per person employed as a proxy for productivity per person is limited, but indicative. In both cases the difference in capital intensity appears to be the determining factor in the level of productivity (measured as dollars per person employed), and the increase in apartment building would explain the rapid rise in Building IVA per person employed. The effect of changes in output (the mix of buildings and structures delivered) will be explored in another post. Why that increase in Building IVA per person employed was not picked up in the GVA per person employed estimates is also an interesting question. 

Research Companion to Construction Economics

Construction Economics applies economic theory, concepts and analytical tools to the construction industry, the companies and organisations comprising it, andthe projects it undertakes. Over time, the field has been extended beyond the minimisation of capital cost on projects to include life-cycle cost considerations, theidea of value, sustainable construction and climate change, and applications of technology. Attention has also  included consideration of companies andorganisations, and strategic, industry-level considerations involving the economy and construction markets, government policy, and international finance andeconomics. 

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The digital construction production system

Where is the technological frontier in Construction?

 

 

The fourth industrial revolution has already affected the construction industry through demand for structures for renewable energy and buildings like data centres, warehouses, ‘dark’ kitchens and supermarkets for online delivery services. Some of these buildings and structures already use forms of applied AI in their management and operation.

 

The construction industry is wide and diverse, and the various parts of the digital construction production system are in various stages of development. Over time the development of AI and associated digital fabrication and production technologies will reshape the existing industry, led by fundamental changes in demand (the function, type and number of buildings), design (the opportunities new materials offer), and delivery (through project management). However, these developments are  

 

Automation technology is at the point where intelligent machines are moving from operating comfortably in controlled environments, in manufacturing or social media, to unpredictable environments, like driving a car or truck. In many cases, like remotely controlled and autonomous trucks and trains on mining sites, the operations are run as a partnership between humans and machines, or as Brynjolfsson and McAfee put it “running with the machines not against them”. These innovations might reasonably be expected to affect site processes and project organization, as concrete and steam power did in the past. Table 1 has examples of where the technological frontier was in 2020 for plant and equipment and construction materials, as an indication of the range and extent of this wave of innovations. Missing from these lists is smart contracts using blockchain. 

 

Invention and innovation based around BIM, digital twins, digital fabrication and advanced manufacturing technology is starting to fundamentally affect the construction production system through economies of scale. Over time this will alter the balance between on-site and off-site production of building modules and components, and how they are handled, assembled and integrated. Because there are many different types of building in many places, production methods vary widely across the industry, so the use of these new materials and technologies will be varied. 

 

Transport costs have always been important, but the option of site production has been limited due to standardization of mass produced components. The combination of BIM, online design databases and digital fabrication allows on-site production of some building components. Combining robotic and automated machinery with digital fabrication and standardized parts opens up many possibilities. 

 

Past technological changes in construction operated over the three dimensions of industrialization of production, mechanization of work, and organization of projects. Automation and AI can also be expected to work along these dimensions as the fourth industrial revolution reconfigures them by linking data through the life of a project. The role of AI enhanced cloud-based platforms that integrate design, production and delivery of components and materials with digital production technologies that allow mass customisation will be significant in the production of components and materials.

 

Table 1. Examples of the construction technological frontier in 2020

Plant and equipment

New materials

Autodesk BUILD Space – Boston UK construction manufacturing hub Exoskeletons – Esko, HULK Remote control equipment – CAT, Komatsu Drone monitoring – Skycatch, Icon, Vinci Smart helmets –  Trimble Hololens, Daqri Platforms – Katerra Apollo, Project Frog Build autonomous skidsteer FBR Robotics ‘Wall as a service’  Otis ‘Elevator as a service’ Sensor fitted cranes Automated engineered wood factories

3D concrete printing with boom system – ICON, Aris, 3D Constructor 3D concrete printing with gantry suspended nozzle – D-Shape, BIG, US Marines Onsite metal printing – GE, MX3D, Aurora  3D printing of combined steel and concrete Roller press printing of smart fabrics  4D printing of shape memory materials  Molecular engineering of materials   Improved concrete additives and sealants Components with cloud-linked sensors Cloud-based fixtures and fittings

Source: Company and industry reports.

 

For mechanization, the characteristic changeability of construction sites is challenging for automated and robotic systems, and it might take decades of investment for machines able to do site work or for humanoid robots to do human tasks. In some case a human supervisor operating a team of robots or several pieces of equipment, each with limited autonomy, might work better. A worker with a smart helmet could monitor these machines both on the project and in the site model. Beyond site preparation however, there may not be many tasks left if site processes are restructured around components and modules that are designed to be assembled in a particular way, and machines to assemble those components and modules can be fabricated for that purpose. For an industry with an aging workforce there is the potential of exoskeletons for site work, a form of human augmentation that combines human skill with machine strength.

 

For organization of projects digital platforms providing building design, component and module specification, fabrication, logistics and delivery can be expected to become widely used. Platforms provide outsourced business processes, usually cheaply because they are standardized, and are available to large and small firms. Also, platforms use forms of AI to monitor and manage the data they produce, the function of intelligent machines. Examples are Linkedin (matching jobs and people), Skype (simultaneous translation of video calls), AWS and other cloud-computing providers, and marketing, legal and accounting software systems. Cheap, outsourced, cloud-based business processes can lower fixed costs and thus firm size, because firms can focus on their core competency and purchases services as necessary as they scale, leading to more entry and more innovation. If these digitised business processes are cost-effective and become widely used, they can provide much of the data needed to train machines as project information managers.

 

The BIM model of the project links the design and fabrication stages to the site and the project[i]. Digital fabrication produces components and modules designed to be integrated with on-site preparatory work and assembled to meet strict tolerances. Project management would be more focused on information management, and the primary role of a construction contractor might evolve into managing a new combination of site preparation work and integration of the building or structure with components and modules, some of which may be produced on-site in a Fab if economies of scale permit. 

 

In this case, the industry would, perhaps slowly, reorganise around firms that best manage on-site and off-site integration of digitally fabricated parts. With outsourced business processes and standardized site and structural work, that would be a key competitive advantage of a construction firm. Firms would become more vertically integrated if they become fabricators as well, reinventing a business model from the past when large general contractors often had their own carpentry workshops, brick pits or glass works and so on.    

 

While firms involved in construction of the built environment are facing technological advances that will affect many aspects of the technological system, this is a process that happens over years and decades. It takes 30 to 50 years between invention of a major new technology like cars or computers and its use becoming widespread, examples are discovering the double-helix and biotechnology, the dynamo and electricity, and the first electronic computers in the 1940s. 

 

How long a transition to a new production system largely built on automation and digital fabrication coordinated by AI takes might take is unknown. While machines can replicate individual tasks, integrating different capabilities and getting everything to work together is another matter. Combining a range of technologies is needed for workplace automation, but solving problems involves specific technical and organizational challenges, and once the technical feasibility has been resolved and the technologies become commercially available it can take many years before they are adopted. 

 

This suggests there will be many new roles emerging in construction over coming years, for project information managers, BIM supervisors, integration specialists and other fourth industrial revolution workers. Because these jobs will be primarily on new projects, they will not quickly replace the many existing jobs in the industry that maintain the built environment. 

 

Nevertheless, the technological frontier is moving again, and new construction projects will generally utilise the most cost-effective technology. Current AI technology provides services such as GPS navigation and trip planning, spam filters, language recognition and translation, credit checks and fraud alerts, book and music recommendations, and energy management systems. It is being used in law, transport, education, healthcare and security, and for engineering, economic and scientific modelling. Advanced manufacturing is almost entirely automated. 

 

In the various forms that AI and digital fabrication takes on their way to the construction site, they will become central to many of the tasks and activities involved. In this, building and construction may no different from other industries and activities, however the path of AI in construction will be distinct and different from the path taken in other industries. This path dependence can vary not just from industry to industry, but from firm to firm as well.

 

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[i] In 2019 the International Standard 19650 was released, providing a framework for creating, managing and sharing digital data on built assets. https://www.iso.org/obp/ui/#iso:std:iso:19650:-1:ed-1:v1:en 

Production of the Built Environment

Industries, Clusters and Sectors

Parts of the economy that involve many different contributors and participants are often called an industrial or economic sector, an example is the non-profit sector with its wide variety of organisations. Although the idea of an industrial sector has no precise meaning, it is often used to describe a loose collection of firms with one or more common characteristics, like ‘manufacturing’ or ‘the business sector’, though firms in these sectors come from many different industries.

The starting point is the concept of an industry, which is defined in the Standard Industrial Classification (SIC) used by national statistical agencies as a group of firms with common characteristics in products, services, production processes and logistics. These firms are classified into a four-level structure. The highest level is alphabetically coded divisions such as Agriculture, forestry and fishing (A), Manufacturing (C) and Information and communication (J). The classification is then organised into two-digit subdivisions, three-digit groups, and four-digit classes.

The boundaries around an industry are tightly defined by the SIC, to allow identification of individual industries as producers of goods and services and measurement of their contribution to output and employment in the economy. However, to produce something supplies are needed, purchased from other producers, and these relationships between industries are also important. For example, bricks are manufactured products supplied to property developers to provide buildings for their customers. Many industries are structured around such supply chains and production networks, and when enough firms share sufficient characteristics they are often described as an industry cluster.

 

An industry cluster brings together a group related firms, and was originally applied in the 1990s to specific locations like the wine industry in California’s Napa Valley or Bordeaux in France. Over time, the concept itself broadened as different types of clusters were identified, such as creative industry hubs or knowledge centres. Two types of industry cluster are: 

      1.      Geographical – industries using the same resources in a specific location

·        Movies – Hollywood US, Bollywood India;

·        IT – Silicon Valley CA., Silicon Alley NY., Silicon Glen Scotland, Bangalore India;

·        Leather goods, spectacles and glasses – Italy;

·        Health – Boston US, Oxford England, Chennai India;

·        Electronics – Guadalajara Mexico, Cordoba Argentina, Guangdong China;

·        Finance – London England, New York US, Geneva Switzerland; and

2.      Vertical – a hub and spoke value chain from suppliers to end products

·        Automotive – Detroit US, Dusseldorf Germany, Turin Italy, Curitiba Brazil

·        Aerospace – Toulouse France (Airbus), Seattle US (Boeing)

·        Smart phones – Guangdong China (Apple), Hanoi Vietnam (Samsung)

Some industries do not have central locations like the clusters in IT, wine, finance etc., or major hubs where production is concentrated like automobiles and aerospace. These industries are built around decentralised production, distribution and delivery networks that make their products widely available to clients and customers. Four examples are:

·        Pharmaceuticals – a globally distributed industry, with countries combining some form of domestic production and imported supplies;

·        Shipbuilding – brings many suppliers together in a few locations;

·        Electricity generation – brings many suppliers together in many locations;

·        Building and construction – the world’s most ubiquitous industry, sharing the most widely used materials of wood, clay, glass, steel and concrete. Is this really a cluster?

 

Building and construction, in fact, is only one of the many industries involved in the production of the built environment. There is a diverse collection of industries that create, manage and maintain the built environment. On-site work links suppliers of materials, machinery and equipment, products and components, and all other inputs required to deliver the buildings and structures that make up the built environment. Consultants provide design, engineering, cost planning and project management services. Once produced, buildings and structures then need to be managed and maintained over their life-cycle, work done by another group of related industries. The built environment also needs infrastructure and services like water and waste disposal, provided by yet more industries.

A dense network of many different firms and participants such as this is often called an industrial or economic sector, because it is too diverse and distributed to be a cluster. There is no definition of an industrial sector, beyond a broad collection of firms with one or more common characteristics, like ‘manufacturing’ or ‘the business sector’, though firms in these sectors come from many different industries. There are also sectors based around a definable market, two examples being:

1.      Defence - there is no defence ‘industry’ because suppliers come from many different industries like IT, aerospace and shipbuilding, but as a sector share resources and clients; and

2.      Tourism - which brings together the contributions of industries like accommodation, tour operators and entertainment. This is why the tourism sector has an annual Tourism Satellite Account produced by the ABS each year.

If the built environment encompasses the entirety of the human built world, then the built environment sector (BES) is the collection of industries responsible for producing, managing and maintaining the buildings and structures that humans build. To be included in the BES an Industry needs a direct physical relationship with buildings and structures. Those industries can be divided into those on the demand side and those on the supply side, like materials or specialised tradesmen, Demand side industries like property developers and facility managers pull output from the supply side, both for new output and for servicing and managing existing assets. Therefore the BES is a sector more like defence than tourism, because it also produces long-lived assets for clients outside the sector (governments and owners respectively) that require repair and maintenance, and that R&M generates significant ongoing revenue for firms across the broad industry sector that produces those assets.

A final requirement is that data on the industries included in the BES needs to be available at a level of detail that separates out BES components of industries like manufacturing and professional services. Generally, this excludes industries such as transport, legal and financial services. These industries clearly play a role in the BES, but that role is hard to identify in Industry statistics because of the level of aggregation in the data. Another complicating issue is that industry-level statistics can vary greatly across different releases by an agency, due to the different data sources and methodology used, and also between countries, whose national agencies typically use their own version of the SIC.

The concept of the BES is broad and extensive, so cannot be precise and exact. While the boundaries of industries and markets are important, in practice the data and SIC definitions are the starting point for the data used. The industries included are selected because they clearly have a relationship with construction, management and maintenance of the built environment. This may not capture every last contribution to the BES, but it does allow the development of a profile of the sector. Measuring the BES provides data on its relationship to the wider economy, and is relevant to a wide range of policies and issues currently facing the built environment.