BIM: Getting started on the 4D planning journey
Building Information Modelling has increased in popularity but 4D planning numbers are lagging. Why?
September 29, 2022
Building Information Modelling (BIM)1 collaborative technologies have increased in popularity, with approximately 71% of construction professionals adopting them and 25% intending to adopt them within the next five years.2 However, when it comes to 4D planning3, the numbers appear to be lagging.4 But why? In this article, Stephen Podesta from FTI Consulting’s Construction Solutions team in London outlines potential reasons behind the implementation issues and the key opportunities present, drawing on his 35 years of experience.
The 3D design model
Almost every pharmaceutical, biotech, power, and process project (and many commercial projects) upon which I have worked as a lead planner or delay analyst since the year 2000 has had some type of 3D design model. In my experience, the process construction sector always seemed to be ahead of the commercial sector in this regard.
3D modelling allows the process designers to place complex and densely packed piping, ducting and electrical systems into heavily serviced buildings within a single design space. 3D modelling tools facilitate quicker, more efficient space utilisation and easier clash detection than 2D drawings alone.
Once the model has been fixed (or frozen) for construction purposes, it is a reasonably cost-effective exercise to drop out ready-made fabrication drawings such as piping isometrics5 from the model.
Using 3D design models for planning the works
My first experience of using 3D design models as a planning aid was in the pharma and biotech industry almost two decades ago. As a project group, we would bring together the lead civil, mechanical, electrical lead engineers and subcontractors into a conference room, show the 3D model on a large screen and then virtually walk through it. The interactions, understanding of the issues, and ultimately the buy-in from the group was definitely enhanced by the 3D visualisation process.
The sequences of installation, layering of high-level services (while assessing the most effective timing of the lifting), the logistics of movement and placement of major pieces of equipment/vessels could be more readily discussed and planned in this type of forum. So, why are these 3D modelling tools not used more frequently for planning?
What are the potential barriers to using 4D for planning the works?
My goal as a planner was to schedule out the design, construction and commissioning phases of a project in a safe, logistical and time-efficient manner in alignment with the stated project goals. Access to a 3D model, and thus being able to use all the useful data within it (for example, construction quantities) has always seemed an obvious choice to me.
There is some potential liability, proprietary, warranty, copyright and other legal issues to consider when making such data readily available across different organisations. However, other barriers that may be holding back the regular usage of 4D planning could include:
- Initial cost of implementation (software and hardware) and the inherent ‘learning curve’.
- Limited universal use within projects – lack of standard process and procedures in place. Insufficiency of coding protocols for objects within the 3D models.
- Non-availability of an integrated 3D design model.
- Cost versus benefit for smaller projects.
- Number of trained staff available.
However, sometimes it might just be because people do not know what is possible as they have not seen it ‘in action’ before.
What are the potential benefits to using 4D for planning the works?
If executed well the benefits of 4D can include:
- Enhanced engagement of the project team in the planning process and thus buy-in to the resultant schedule.
- Ease of communication of the schedule — a picture paints a thousand words!
- Improved demonstration of potential (and actual) delay and disruption issues.
- Better spatial and sequential coordination.
- Enhanced visualisation of logistical issues.
- Reduced likelihood of missing project scope from the schedule.
- Quantities for scheduling are easily accessible from the embedded 3D design model.
- Assistance to the safety management of the project.
Getting started with 4D planning
So how does one get started from ground zero? My advice would be just to put some time aside and have a go!
Firstly, ask your IT department to load some free 3D model ‘viewing’ software onto your computer.6 Then obtain a compatible 3D model for your project7, and after that just play with it as a bit of fun. You should not be able to do any harm if you are using a standalone version of the model.
Get comfortable spinning the model, zoom in and out, and find out how to walk around the model. Learn how to filter objects, for example, filter out only the steel frame from the rest of the structure, the ductwork or maybe just the hot water piping system. Obtain a feel for how the model is broken out into its object tree (work breakdown structure). The best 3D packages are usually reasonably user-friendly and intuitive in respect of using these basic functions.
Research the 4D software tools currently available and find something that meets your technical needs and budget. The 4D Construction Group8 have created a guide9 that may be able to assist you in doing this. The major software suppliers will often provide training themselves or advise you where you can obtain some.
Will there be a catalyst for speedier uptake like the pandemic did for remote working?
Maybe usage will jump when the generation of people who played Minecraft10 back in 2010 (and other such 3D computer games) become the main players in the construction industry, as alluded to by an article published by BIM+ last year?11 Or maybe it will just be something that grows organically as the tools become more affordable and the skills become more widespread?
As a planner who wants to obtain buy-in for a programme and then be able to bring life to that plan and speaking as someone who now needs to explain the impacts of delays to people who might not be up to speed with scheduling terminology12 and who do not readily relate to Gantt charts13 (bar charts), the benefits seem distinctly tangible.
As is often stated in Strictly Come Dancing14, maybe it is all about ‘the journey’ and ultimately, having the impetus to take the first steps on that journey…. Slow, slow, quick, quick… slow. Keep dancing! Stephen Podesta is a planner and delay analyst who advises both domestic and international clients and contractors on construction time-related matters.
1: Dr Stephen Hamil, 09 September 2021, NBS, https://www.thenbs.com/knowledge/what-is-building-information-modelling-bim: “BIM is a process for creating and managing information on a construction project throughout its whole life cycle. As part of this process, a coordinated digital description of every aspect of the built asset is developed, using a set of appropriate technology. It is likely that this digital description includes a combination of information-rich 3D models and associated structured data such as product, execution and handover information. Internationally, the BIM process and associated data structures are best defined in the ISO 19650 and 12006 series of standards.”
2: NBS Digital Construction Report 2021, incorporating the BIM Report. NBS Digital Construction survey report V2 2021.11.11.
3: 4D planning involves linking the 3D model with schedule information. This allows the timing and sequencing of the 3D model components to be visualised through time via a graphical rendering i.e., running the 3D model through time and thus effectively adding an additional dimension to the 3D model, the result being commonly called 4D.
4: Logikal Project Intelligence, 2020 Project Controls Survey Report, 2020-Global-Project-Control-Survey-Report-LogiKal-2, page 9.
5: A piping isometric is a representation of a single pipeline in a process plant that will detail exact dimensions and provide an accompanying Bill of Material (BOM) for that particular line. It is normally presented in 2D but in a 3D-like format using an axonometric projection with three coordinate axes.
6: Most of the large reputable software packages that are used for 3D design also supply free ‘viewer’ software packages. They usually do not have all the ‘design’ functions and capabilities that the full, and more expensive, versions would comprise, but they are generally good for working around the model and getting a feel for the output that is the 3D model itself.
7: The design engineers on the project should be able to facilitate that in terms of providing the appropriate file extension type of 3D model file.
8: A group of people that advise that they “have no parent organisation, vested interests or sponsors, which allows us to be flexible, open, impartial, and agnostic”. Their mission statement being: “Our mission is to improve the uptake and use of 4D Modelling in construction. We do this by raising awareness and sharing knowledge.” https://www.4d.construction/
9: 4D Construction Group: 4DC Group Solutions Review 2021.
10: Minecraft is a video game developed around 2010 which is set in a 3D world in which the game player discovers and extracts raw materials, crafts tools and builds various types of structures or earthworks.
12: Glossary of ‘planning/scheduling’ terms such as critical path method, predecessor/successor logic linkages, activity constraints and activity float (free, total and terminal) and the like.
13: Collins dictionary: a chart showing, in horizontal lines, activity planned to take place during specified periods, which are indicated in vertical bands. Also, often known as a barchart.
14: An annual celebrity/professional dance competition which is produced and broadcast on the BBC in the UK. Its sister TV programme in the USA is called ‘Dancing with the Stars’. The same basic format has similar versions televised around the world.