Home Articles Intelligent Buildings: A tale of two scales

Intelligent Buildings: A tale of two scales

The long-term relationship between the building and the  evolving city where BIM-enabled buildings become long term multi-dimensional sensors must be the goal. By Tony Mulhall

Although it is difficult to imagine a city without buildings, when we talk about smart cities, unconsciously we may well be talking about the city as an abstract amalgam of all these disparate buildings without recognizing that the individual structures are originated as discrete projects in themselves. At the urban scale, we may be making plans for smart cities without being fully conscious that at the scale of the building there is a distinct difference between how the building is procured and for what purpose, and how the city is run and whom it serves.

In commercial and governance terms, the building and the city originate as completely different enterprises. The building originates mainly through a private procurement process with all of the characteristics of private sector motivation, proprietary commercial interests and the confidentiality requirements that surround such an enterprise. In contrast, the city has emerged by way of agglomeration to serve the needs of the citizens, governed by concepts of communality, democracy and openness.

Not surprisingly then the digital manifestations of the city and the building are being generated separately at these two different scales, with distinct objectives, wrapped in quite different concepts of good governance. The concern is that the city and the building may not be talking to each other at these different scales and from these different origins. As a result, we may be missing out on a whole range of opportunities for the interoperation of both. This article supports the argument for a new business model to integrate these two scales.

Different kinds of ‘smart’
Figures 1 and 2 (below) provide typical representations of these two different scales. Fig 1 is a digital version of London, based on the space syntax method of analysis developed at UCL delivered on a 2 D GIS platform. Fig 2 is a Building Information Model of an individual building developed on a 3D platform.

Figure 1: London, Space Syntax, UCL Figure 2: BIM Model of an individual building

How these two systems interact has taken on a new urgency in the United Kingdom. By 2016, the UK government has stipulated that all centrally-procured projects should be planned to BIM Level 2, i.e., a managed 3D environment with data attached, but created in separate discipline based models that may include construction sequencing and cost information. Essentially, a building design based platform geared to the requirements of building procurement. By contrast, in terms of city planning 2D GIS has been the typical platform on which municipalities build the digital city although increasingly this is now being realized as a 3D GIS model.

Cultural difference
Despite the obvious interdependencies between buildings and cities, the following clear cut distinctions emerge:

  • City scale vs site scale
  • City planning vs building design
  • Public interest governance vs private interest governance
  • Public sector objectives vs private sector objectives
  • Public data vs private data

At the higher level, the city tends to be urban policy driven for plan making, whereas the building is developer/investor-led focusing on the creation of a secure property asset. Alignment of these interests will require the development of new business models combining the open sharing culture of city governance with the private proprietorial demands of commerce, with necessary safeguards for both.

The business end of smart
The UK government regards the ‘smart’ agenda as essential to delivering competitive advantage in the global economy. It sees the development of expertise in this area as highly transformative in terms of generating new services and new expertise for citizens as well as keeping the UK at the forefront of developments. But it is not just about economic development. As well as creating a new economy, the smart city agenda is about ‘effective integration of physical, digital and human systems in the built environment’.

Economic drivers
At a basic level, the economic drivers for smart cities are about managing all of those ‘dumb’ 19th century networked infrastructure more efficiently through the application of sensors, actuators and a host of other digital aids to service maintenance and delivery. The benefits are reducing outages together with more efficient distribution.

In terms of smart buildings, there are clear economic benefits to be achieved with savings on costs of up to 20% predicted through the application of Level 2 BIM.

But there are challenges to effective exploitation of data:

Additional costs: Ensuring that data being collected for internal use by an agency is done in an open, standards based format making it widely available will have additional costs.

Data security and privacy: Maintaining data security and privacy in a way that will give confidence to those providing data and individuals to which data relates.

Workable commercial arrangements: Income from data needs to be distributed fairly to a number of different agencies reflecting costs of making data available and value that data would have to others.

Data Capture: Lack of a consistent approach to capturing data at every scale in a city specifically data modelling processes used by city planners and those used by architects.

Professional challenges

  • Different professionals are using different data modelling systems.
  • Scale gap between micro, building focused scale of architect and the macro city focused scale of planner.
  • Meso scale (street) where important social and economic life takes place, falls through gap. It is also where most of the city’s networked infrastructure is located.
  • Identification of useful data: what data is most useful; how could it be most easily collected and made available and what exactly could it be used for?
  • Lack of appreciation of potential of digital design: architects and planners use computers but only to help do what they do already. The potential to design in a different way may be ignored.

City Information Modelling
It is not difficult to see the connection between digital modelling at the building level and digital modelling at the city level. It has been observed that when BIM is more widely adopted the possibility of City Information Modelling (CIM) will emerge.
The capacity to move beyond policymaking and begin managing the resources of the city to achieve ‘more with less’ is a goal worth pursuing through smart technologies — less waste in locations with abundance; better services for longer periods in places with extreme scarcity. So when we talk about the city and its infrastructure, clearly the need for interoperability at all scales becomes fundamental to effectively mediating between building and city.

CIM could address one of the key deficiencies in the construction and development process caused by the lack of precise, open-source data about the most basic daily challenges — the location of underground services for the purpose of connection or avoidance. Repeated failure to capture this information for shared use is one of the most contentious, disruptive and time consuming aspects of urban development.

Whoever might be the CIM custodian would need to promote the benefits of sharing information to developers and contractors and then ensure that the resulting CIM model is shared on a commercial basis informing and enhancing future projects.

The long-term relationship between the building and the evolving city where BIM enabled buildings become long term multi-dimensional sensors in the city must be the goal. Clearly, there will be a requirement for planners and architects to use a common approach to enable this to happen. But there are also cultural differences between those operating at the city level and those operating at the level of the building which will also need to be overcome.


  1. ‘Digital Built Britain’ UK, Department for Business Innovation and Skills (BIS) 2015.
  2. ‘Smart Cities – guide to the role of planning and development process’ British Standards Institute, PD8101:2014 (BSI) UK, 2014
  3. PAS 180 – Smart Cities. Vocabulary; BSI UK, 2014
  4. ‘Smart City Framework – guide to establishing strategies for Smart Cities and Communities’ PAS 181:2014 British Standards Institute (BSI) UK 2014
  5. UK Urban Catapult Seminar, London, 2015
  6. ‘City Information Modelling’ RICS Modus, London, February 2015

Tony Mulhall
Associate Director, Land Group, RICS
[email protected]