Birmingham City University campus redevelopment has been one of the largest university BIM projects in the UK and among the first to deliver fully integrated modelling across design, construction and operational management.
A lot has been said about BIM, yet there’s still a shortage of detailed case studies that clearly demonstrate why it’s better than traditional models.
NG Bailey’s work alongside Willmott Dixon on Birmingham City University’s campus development using BIM Level 2 has allowed the company to create a much-needed showcase for the industry’s future.
It combines a technological leap with a determination to drive up standards and propel them into a new era of unprecedented efficiency gains, as the university modernises and consolidates its facilities.
The level of detail in the modelling has made this project one of the most advanced in the UK, enabling the team to push the boundaries from design through construction and into facilities management.
Saving both time and cost
On the first phase alone, the approach reduced the build programme by eight weeks, securing savings of £240,000.
The accuracy of the modelling meant no redesign was required to rectify any clashes encountered during phase one’s construction.
The second stage, when it completes this month, is poised to deliver similar benefits, having identified more than 25,000 design clashes during preconstruction.
“The team constructed a detailed model in line with BCU’s specific project requirements, which included a 35 mm level of accuracy”
NG Bailey has been responsible for the delivery of the design, supply and installation of mechanical, electrical, ICT and public health services of the 22,669 sq m building.
Spread across two blocks – one six storeys high and the other on five levels, each with roof plant rooms, the building is also designed to be sustainable and technologically advanced.
As part of the first phase, the team had constructed a detailed model in line with BCU’s specific project requirements, which included a 35 mm level of accuracy between the actual structure and the model.
This level of accuracy has been maintained on phase two, with the addition of all electrical components, including fire and security services to the modelling.
The use of BIM technologies on this project has improved the quality and speed of construction, but will also provide the university with cutting-edge facilities management and maintenance capabilities.
BIM has provided the team with a number of opportunities to take all the information about project elements, display the data for each object or component and control the application and appearance of different views.
“FM employees working in the building can scan a barcode above a door frame using their iPad/iPhone to see a huge range of data and images”
Using Autodesk Revit, NG Bailey was able to establish a library of components down to the detailed level of wall sockets and radiators, as well as the assignation of specific electrical circuitry at individual accessory detail.
This is far in excess of accepted current practice, but aligned with the client’s stringent employer’s information requirements.
This provides opportunities for managing each item or object throughout its life within the design, construction, occupation and maintenance of the building.
New industry standards were also adopted for codification of plant and components, enabling FM employees working in the building to scan a barcode above a door frame using their iPad/iPhone to see a huge range of data and images – for example, knowing if the right light bulbs were in stock.
A major advantage of BIM above traditional modelling is that the data in the model can be accessed in a number of different ways to suit the required application.
“If the data changes, the text on the sheet will automatically update, saving time manually updating data sheets”
Annotations on a layout can be used to access the data directly, which increases efficiency by avoiding the need to type and also reduces the potential for errors.
Another benefit is that if the data changes, the text on the sheet will automatically update, saving time manually updating data sheets and, therefore, costs.
The same data can be viewed in a customisable schedule, providing summaries of equipment for estimating, a room-by-room breakdown for installation, or asset management.
The data can also be modified directly in the schedule and any changes made this way will also be updated on any sheets that reference that item.
Transparency through asset information
A great aspect of the modelling used on this project was the asset information through Autodesk BIM 360 Field.
This involved exporting the models from Revit software with the data preserved, meaning engineers in the field could access the models through tablets.
This gave direct access to the 3D model and all the equipment data, allowing them to clarify the arrangement of services, especially in congested areas, including behind access panels and above ceiling systems.
Systems are used in Revit to classify distinct duct and pipe runs. Each air-handling unit was assigned to a different system and any equipment connected to it inherited that system.
“Colours were applied to each system type through the system browser, allowing the co-ordinator to identify the system in any view”
This enabled the engineers to trace the route and see immediately which AHU a specific grille was supplied by.
During the modelling process, colours were applied to each system type through the system browser, allowing the co-ordinator to identify the system in any view.
Once connected, the systems can be used for flow calculations and to quickly check whether the ductwork is complete.
Object properties can also be used to control the visibility of each view.
In Revit, categories are used to divide the elements into broad groups, which can be turned on and off in a similar way to layers in AutoCAD.
However, the inclusion of embedded data builds on this by allowing the graphics to be changed based on the values of certain parameters.
For phase two, filters were created to select cable tray and fittings based on the service type property such as LV, data and security.
Different colours were then applied to each of the selections to help understand the different containment routes.
NG Bailey also used the colour fill legend tool, which automatically applied a colour to the services based on the value of a parameter.
“By taking a flexible and proactive approach to BIM, the team on the BCU project has ensured minimal redesigns”
This was used to colour the pipes according to their size on the heating layouts so the engineer could see at a glance any sizes that didn’t match the schematic.
Other benefits realised on phase two were derived from all contributors using the same software.
Interdisciplinary co-ordination and clash detection were carried out using BIM 360 Glue.
Each model owner published their model directly from Revit and clashes could then be pinpointed using the Revit add-in.
Once these had been resolved, they were automatically removed from the clash list at the next issue of the model.
By taking a flexible and proactive approach to BIM, the team on the BCU project has ensured minimal redesigns were required to rectify any of the identified clashes.
The level of detail and visual accuracy in the modelling also meant the project team was able to discuss and explore the design with non-technical personnel, improving client expectations and understanding at every stage of the project.
George Cunningham is design and engineering manager, NG Bailey Midlands and South-west