Reality check

With so many different stakeholders using BIM, a single file for all their data is just the job

At regular attendances at MelBim conferences recently I have found a small cross section of the building community doing amazing things with technology.

3D scanning has been around for a while but hasn’t really hit mainstream construction. Rather than replace traditional surveying techniques, it is used as a verification tool. My experience with 3D scans has been a painstaking process to rebuild geometry from groups of points, as we have lacked solid translation software and computing power capable of extracting usable surfaces from the point cloud. The service engineering arm of Arup outlined an interesting approach using Lidar scanning to upgrade a mechanical plant level. They started by scanning the existing space to create a point cloud, then extracted sets of points from it to build surface geometry. Next a 3D model of all existing and proposed services was composited and placed in a single virtual reality environment complete with construction notes and specs. After construction a second scan was taken and the resulting point cloud overlaid with the proposed model for comparison. Errors and omissions in the construction were quickly identified and resolved, and produced an extremely accurate data rich ‘as built’ model complete with specifications for the facility management team. This approach is a defining moment in building modelling as it will create a single digital file containing the entire specification linked to the appropriate geometry, with sets of proposed and constructed information in a walkable virtual reality environment.

This approach is a defining moment in building modelling as it will create a single digital file containing the entire specification linked to the appropriate geometry, with sets of proposed and constructed information in a walkable virtual reality environment

Hansen Yuncken is also blurring the boundary of virtual and real space with iPad tools that allow contractors to view the BIM model from the real world location. Contractors can peel back layers of the building and see specific structure, services and finishes. If a clash is found they can take a photo of the existing conditions, mark up the model view and submit as a detailed RFI back to the design team without leaving their current task, saving itself huge amounts of time. Every element in the virtual environment contains a unique ID linked directly to a live BIM model. The design team reviews those elements identified in the clash using programs like Informa, which catalogues emails, notes, site photos, reference material and even individual BIM elements in a 3D environment by creating customised searchable attributes, similar to those used by search engines. What is amazing is that once the BIM element is identified, the file and 3D view linked to it will automatically open for the user.

These conferences reveal the diverse mix of stakeholders in the BIM world. Architects, engineers, quantity surveyors, manufacturers, contractors and building management teams now have a single file in which to input and coordinate their industry specific data. Instead of searching through files and folders, it is possible for the first time to walk through a virtual space rich with information and extract specifications and data embedded in the geometry.

Alan McLean is an architect at Bates Smart Architects in Melbourne