Offsite fabrication or prefabrication, in its simplest form, means assembling components offsite in a controlled environment, prior to installing onsite.
It can apply to almost all kinds of building construction and even though it’s not possible for everything, in more cases than less, it’s usually a better idea to go for a prefabrication approach, rather than going for the more traditional route.
Prefabricating components offsite can deliver a project 30% to 50% faster than traditional methods, according to the Modular Building Institute. This method has proven to increase efficiency, and increase labor productivity by 89%*, which is one of the reasons why its popularity continues to grow YoY. Contractors are now leaning more towards this technique, especially after seeing true engineering marvels being erected, that wouldn’t have been possible without offsite fabrication. Dubai’s Museum of the Future, for example, is a quite a complex structure and would have ended up taking triple the time it originally took for formation as all its structural steel components in its entirety, were fabricated off-site by Eversendai Engineering.
Additionally, innovative technology and concepts are making offsite manufacturing easier to implement – mix use of scanning hardware like Trimble’s TX6 and TX8, combined with state-of-the-art software enabling data to be displayed and communicated with precision, for example, allows seamless communication between engineers, consultants, MEP contractors, etc.
The new prefabrication processes in this day and age are a huge step forward for the construction industry, and technology plays an imperative role in its progression.
Saying that, the indication here isn’t that offsite fabrication is a new practice that was just recently adopted by contractors. In fact, the idea behind prefabrication is not even close to revolutionary as it dates back to the 1900s – the issue with it has always been its practicality. Efficient implementation and execution of a project (of any size) that requires offsite fabrication, requires an unblemished level of communication and connectivity between stakeholders and to achieve that level of communication has had its own challenges; until today.
PREFABRICATION LED TO MORE WORK AND HIGHER COSTS - NOT ANYMORE!
In some circumstances historically, manufacturing components offsite actually led to more work and expenses due to an apparent gap in communication. From the blueprints exchanged between stakeholders to the actual work done on-site, if communication is not accurate, there is quite a bit of a window for errors that may result in rework, which in turn, will end up in higher project costs. The same goes for offsite fabrication, as the design drawings need to be detailed to the highest level so that there are no technical hitches at the installation phase; even a slight slip-up after the components have arrived at the location can be catastrophic as it causes delays in assembly.
When tolerances are within 1/32 of an inch to ensure a given slab or a beam needs to fit exactly where it’s supposed to, there is always a risk that the result of the prefabrication might be off an inch or two. More often than not, previously, it was up to the field installers to figure out a way to make it work, maybe scrape a few pieces here and there or remake the component completely. In either case, rework causes delays, extra man-hours, cost and eventually, delays in project delivery.
HOW CAN WE ACHIEVE THE ULTIMATE LEVEL OF EFFICIENCIES?
To overcome these conundrums, it’s evident that like in any other relationship, communication between stakeholders of a project is crucial. In a conversation with Tareq Al-Masri, the Regional Director of Sales and Channel Sales for Trimble Solutions Middle East, he mentioned, ”As one can imagine, fabrication offsite does not only require drawings done with precision and with the highest level of detail (LOD). How this data is shared with other contributors, how efficiently are changes communicated, execution of tasks, easy access to data, all of them play a crucial role in a successful execution of any project.”
So, how can one achieve this level of efficiency where communication needs to be in real-time, especially when dozens of stakeholders are involved and need to exchange large data files like detailed 3D ‘as-built’ models for progress monitoring, site modifications, accurate laying out, etc.?
"Luckily for us, we are living in an era where technology and digitalization are thriving more than ever. We at Trimble realize the requirement and subsequently, the significance of a connected workflow. By equipping the industry with the right tools and ensuring a fluid workflow throughout the construction lifecycle, Trimble has made communication in real-time a norm. From the desktops where the designers sit, to the tablet devices at the job site, to the off-site fabrication facility, and back again; everything can take place concurrently. Needed adjustments can be updated for everyone to act upon, and multiple departments can be involved in exchanging huge digital files."
According to Tareq, one way of achieving this ‘nirvana’ in communication within the construction industry, is by using Trimble’s collaboration software, Trimble Connect. "This cloud-based software has practically eliminated the communication gap between stakeholders by enabling seamless sharing of 3D models with detailed chunks of data." Trimble Connect allows teams to monitor project progress, assign team tasks as well as communicate changes to all members instantaneously. Also, as all this information is shared using a secure cloud-based platform, these means that the data can be accessed anywhere at any time, without the use of heavy storage devices.
Tareq Al-Masri continues to explain the core of Trimble’s processes through its 3 C’s, i.e.:
- All phases and trades are Connected
- Models and workflows are Content-Enabled
- Constructible models drive smarter workflows
He explained that while Trimble Connect can be used as a good example of a truly ‘Connected’ workflow where all stakeholders can use the platform to exchange data to stay "connected," Trimble’s SysQue, which is also a cloud-based platform, is a good example of a "Content-enabled" workflow. As SysQue is specifically for MEP designers and contractors, the software includes manufacturing-specific MEP content that is ready for fabrication. It acts as a digital asset that provides the technical information, for example, geometric parameters to define physical objects like a building component, length of pipe, fabricated housing for machinery, etc.
This content-rich platform allows the experts at every phase of the construction project to easily collaborate to turn an architect’s initial idea into a completed structure.
Lastly, let’s talk about Trimble’s ‘Constructible’ workflow, which simply means that the data and information of a project should be so accurate that it can be taken to the job site as-is and the “constructible” model can be accurately replicated on-site. The more constructible data you put at the very beginning, the better the results are going to be throughout the whole process as a result of lesser RFI’s and clarifications on design intent and information from the get-go!
Taking that into perspective, Tareq Al-Masri gave an example of Trimble’s flagship product called Tekla with its various software suite. Tekla Structures, which is one of the products from the Tekla suite, is a building information modeling (BIM) tool that is able to model structures that incorporate different kinds of building materials, including steel, concrete, timber, and glass. The software allows structural drafters and engineers to design a building structure and its components using 3D modeling, generate 2D drawings and access building information anytime, anywhere. These exceptionally detailed models are fully constructible; meaning, the level of detail (LOD) on these models are so accurate that they can be scaled and erected on-site as is; like an exact digital twin.
Talking more specifically about offsite fabrication, Tekla has another newly launched product called Tekla PowerFab, which in itself has a comprehensive suite of software that provides contractors a systematic and collaborative approach to managing their entire fabrication workflow. Fabricators as well as other departments involved, for e.g. procurement, inventory, etc., can view the status of the projects, track production LIVE, manage inspections and even share granular level access with clients.