It is worth concentrating on the ‘Information’ part of B’I’M before addressing the actual BIM process itself. Information always needs to be collected and contained in a physical object or system. From a historical point of view, this could have been on many drawings or nowadays a ‘project library’ could be made available for the reader or viewer. This really is the same with BIM; however, the whole project information is not just available as an online encyclopaedia, but broken down to object-level nuggets of information for ease of reference.

A product model can be built or defined with a 3D or 4D application, where the latter is the 3D information which also encapsulates the relevant time information. This can also include manufacturing information, start and completion dates, maintenance information and even the required special demolition procedures, as the model can support the full life cycle of the building or project. However, the BIM model is not limited to just 4D information, as costing can also be included, which is sometimes referred to as 5D information, or anything else that the user wants to track (nD information) and control.

Sometimes, BIM is thought to be just another service that provides users with instant online access to an ever-increasing stream of constantly evolving, instantly updating digital data. However, if the processes are in place then real project control is possible. Many times it is said that: ‘Nowadays to change a pump physically on a building site is relatively simple. However, changing all of the 3D models, drawings, sketches, specifications etc. is the hard and time-consuming part.’ Adopting the BIM process will revolutionize this, as the information has only to be changed once with authoring the application, after which the rest of the design team members can simply reinsert the new ‘reference model’, with all the latest information, ensuring all the models are up to date.

General computer-aided design (CAD) tools were used for a while, leading to bespoke solutions which were developed to suit each industry or design team member’s requirement. For example, tools used by architects would require different functionalities from the toolkit required by engineers. Also, a structural engineering application would have different drawing requirements from a mechanical, electrical and piping (MEP) solution. It is interesting to note that in many companies the technicians will produce the drawings, with engineers just resolving typical project sections or sketches.

In the building and construction sector, ‘information modelling’, is normally defined as the computer representation of a building or structure, including all the relevant information required for the manufacture and construction of the modelled elements. The elements or objects are required to be intelligent and should therefore know what they are; how they should behave in different circumstances and know their own properties and valid relationships. A simple example of this would be the reinforcement in a pad foundation. If the foundation size is modified, then the embedded reinforcement should dynamically update and reposition itself accordingly. This is very different from a computer-generated model, which is constructed for purely visualization purposes, where every object is a non-related element.

The structural steelwork industry is normally recognized as the lead sector in 3D modelling solutions, and their developments can be traced back over the last 30 years with applications such as the forerunner of Tekla Structures. This type of applications allowed the 3D steel frame to be modelled and the connection applied by the user-defined macros, which allowed the automatic production of general arrangement drawings, fabrication details and then, after a few more years, the development of links to CNC (computer numerically controlled) machines, for cutting and drilling of steel profiles and fittings.

Once the 3D modelling technology was extended to include parametric modelling (true solid objects), clash detection systems were then developed. Hard or soft (allowing for access) clash detection allows application to identify any possible material overlapping conditions or objects existing in the same space.

Nowadays, globally unique ID or globally unique identifier (GUID) is available in most applications, which are unique strings usually stored as a 128-bit integer associated with the objects. The GUID is used to track the objects between applications for change management. Some systems allow the support for internal and external GUIDs. The term GUID usually, but not always, refers to Microsoft’s universally unique identifier (UUID) standard.

In the initial stages of BIM, only drawings and reports were made available to others, as the actual BIM model was always confined to the office where the more powerful computers were situated. However, as computers advanced, the models are now accessible on laptops and, over the last few years even on tablets for site use, either located on the device or available from the cloud.

BIM enables multidimensional models including space constraints, time, costs, materials, design and manufacturing information, finishes, etc. to be created and even allows the support for information-based real-time collaboration. This information can be used to drive other recent technologies including city-sized models, augmented reality equipment used on site, point clouds of existing buildings and equipment, radiofrequency identification (RFID) tags to track components from manufacture to site and even the use of 3D printers.

It may be useful to consider the players who would want to have access to the BIM models. Not limiting the list they could include – the internal and external clients, local authorities, architects, engineers (structural, civil and MEP), main contractors, steelwork and concrete subcontractors, formwork contractors and all site personnel. Until recent years BIM has just been available as a solution for architects, engineers and steelwork contractors, etc., leaving everyone else just to work with 2D drawings that may be industry-specific, but not being totally readable without knowledge of that environment.

Various references have been made to architects’ BIM model or the structural BIM. However, they really are the same, as the boundaries between their models and their content are reducing all the time. Architects’ BIM models will include structural member; however, the models that they produce do not normally require including the material grades, reactions and finishes, whereas the model produced by the steelwork contractor will include at least the manufacturing details and all the information necessary to order, fabricate, deliver and erect the members. The MEP contractor could also define the site fixings on their version of the model, as the contractor will want to know when the assemblies will be delivered to site, where it will be fixed or poured, and how much the item costs. The client’s view of the same member would be for control and for possible site maintenance. For this reason, various models are created in the ‘best-of-breed’ authoring applications and shared with other design-team members as reference models, which are normally in the form of industry foundation class (IFC) files for all structures except the plant and offshore markets, where CIMsteel Integration Standards (cis/2) and dgn format files are the dominant interoperability transfer model formats.

It is so much easier to work with a BIM model and to explore the building in 3D with rich information, than looking at hundreds or thousands of drawings and having to understand the industry drawing conventions. Now a user can simply click on to an object and obtain all the information that they require either through the native object, if on the authoring application, or through the reference model or even from a viewer or collaboration tool directly from the cloud.

The main aims and objectives of the working group are to:

The general recommendations were to:

The report also defines the project BIM maturity levels, from level 0 to level 3 and as a quick summary:

The UK Government’s main targets in the report were:

COBie information is a formal schema that helps design teams to organize architectural BIM object information into spreadsheets that are normally shared with other project players for facility management.

Also with the initiative from the BIMForum (www.bimforum.org), there is currently much interest in the level of development (LOD) of the BIM model objects, so the client can obtain a clear picture of their expected BIM deliverable quality. For full information see www.bimforum.org/lod.

In very general terms, these levels are:

With Tekla BIMsight the user can:

Tekla BIMsight can be downloaded from www.teklabimsight.com which also includes video tutorials and a user forum.

In addition to Tekla BIMsight, Trimble Solutions Corporation also produces Field3D (www.teklabimsight.com/tekla-field3d), which is an enhanced collaboration tool that runs on both Apple and Android devices and also has a cloud service option.

It is always hard to establish the return on investment and project savings with regard to any software systems. However, as the BIM project is created within the memory of the computer before involving any materials or site personnel’s time the change is inexpensive. Various reports and white papers regarding the cost of change and constant remodelling was one of the reasons for the UK Governments BIM initiative.