Creating Intelligent Digital Built Environments
By Daniel Kazado and Ahmet Çıtıpıtıoğlu for Autodesk University
Building Information Modeling (BIM) has gained enormous traction in the design and construction of a project. Facility owners and operators are increasingly recognizing the value of utilizing BIM models for post-construction use throughout the lifecycle of their facilities and assets. As a result, there are higher expectations and an increasing set of BIM requirements. Models are to reflect the as-built conditions accurately and contain or link to information that is useful to Facilities Management (FM) and Operations.
Under the Public Private Partnership (PPP) framework TAV Airports execute Built-Operate-Transfer (BOT) projects where typically TAV will design and construct airport facilities in return for the concession to operate the airport for 25 to 30 years. Such a long horizon makes maintenance of its investments ever more important to ensure efficient operations and reduced risks to the long-term investment. Combining its design, construction, and operation know-how of TAV Airports and TAV Construction, TAV Integrated Solutions has been implementing innovative tools and technologies like BIM at its airports for the past several years.
BIM for Facilities Management
There are several considerations to take in to account in developing BIM and GIS data models on projects with the objective to improve operations and facilities management. Lack of a proper approach and planning most likely will result in models with insufficient structure and content to be useful for their objectives, risking extensive and expensive rework.
Using BIM as a platform to integrate and supplement existing digital infrastructure such as an asset management system, computerized maintenance management system (CMMS) or BMS/BAS enables better performance for operations, energy management, sustainability, and overall better business.
There are several motivations for such an endeavor:
- Contractual requirements
- Information mobility
- Digitize and future proof data
- Capture and coalesce information
- Information granularity
- Know what is managed
- Utilize extensive integration opportunities
The impact of the accumulated information with BIM transcends the design and construction phases. When comparing cost and duration — operations and associated maintenance cost (OPEX) clearly dominants the cost of the capital investment (CAPEX). The OPEX can benefit from the improvements by utilizing BIM. Comparing the CAPEX and OPEX of a midsized airport (shown in the figure below) it is clear that there is greater value to be gained from BIM on the operations side when compared to the design and construction phase.
Beyond the use of BIM during design and construction there is much to gain in the long run throughout the facilities lifecycle and this is reflected in the recent surge of BIM delivery requirements aimed at FM use within project specifications on a wide range of projects including airports, high rises, data centers, and multipurpose developments.
Though the objectives of BIM model use following construction are typically not well elaborated. This makes it challenging to ensure models are authored so to be useful for the intended purpose of the facilities operator. The following sections will elaborate on the steps toward using BIM models for creating intelligent digital built environments.
Understanding the Process for BIM-FM Integration
Buildings Are Data
What will happen to the information delivered on drawings? For operations will they be accurate or even accessible many years later? This is the essence of our motivation to capture and deliver construction data digitally for future use during the lifecycle of the facility. We are now building both digitally and physically.
The steps involved in taking data and turning it into useful information are common to several functions during construction and after; e.g., design, modeling, site inspections for QA/QC or HSE, for FM for work orders, etc.
- Data authored or registered by some means (i.e., pen and paper, sketches, drawings, BIM models, mobile tablet, etc.)
- They are stored via some medium (i.e., binder, database, model, Excel, etc.)
- Shared through some means such as a Common Data Environment (CDE), email, transmittal letter, etc.
- Finally, data can be processed, reported to have a higher understanding of the data presented — meaning information
There are three main cornerstones in making this happen:
- Technology > Fairly matured
- Process > Needs to be developed to ensure delivery of objectives
- People > Need to be trained to competencies to use the technology and follow the processes
Allocating the funds to hire the right people or train staff to develop and execute the processes is a good start. It is essential for the client/operator to establish all guidelines within a BIM Execution Plan (BEP) where all the objectives and requirements are defined and documented in detail, at a minimum covering the following:
- BIM content and attribute definitions
- BIM asset element requirements
- Existing facility BIM model requirements
- New and future facility BIM model requirements
- BIM content update methodology
- Data management
- BIM hardware and software updates
- BIM management workflows
The BEP developed by the client/operator is a document that covers all aspects of BIM use throughout the lifecycle of the facility. It is the parent document that dictates all future projects which will have their own separate BEP. This is to ensure all future development and additions to the facility BIM database are consistent and compliant with systems in use. Each phase of each project will require its own BIM Execution Plan developed by the responsible consultant or contractor.
What Is “a” LOD 500 BIM Model?
It is common for project specifications to require as-built LOD 500 BIM model delivery at the end of the project, though there really isn’t such a thing as “a” LOD 500 model. A model will contain elements at various levels of development. Therefore, we use LOD matrices for each element type and describe all associated visual and attribute information to ensure a mutual understanding between all parties. MEP system information is also essential for operations and this information needs to be identified through the BIM model as well.
Delivery methods such as COBie which describes the means to compile/aggregate data from subcontractors, alone is not descriptive — specifically about the naming and content of information. Nomenclature between design and operations may also vary — FM staff may not identify the Supply Air System the same way as specified during design or construction. All this needs to be defined prior to any modeling.
Anyone who googles BIM will find several versions of charts showing each phase of a building lifecycle from conception to demolition surrounding a central BIM model. Talking about such a cycle around “a” Central Model from start to end is an oversimplification of what really happens. Rather than having a single BIM model, typically there are several models for each discipline split per floors or zones as necessary which are constantly updated throughout design and construction.
Models are updated and combined together (federated), elaborated, and updated, and this continues where by the end of a project several versions of several models have been generated and used as reference for coordination and data drops. This is part of the challenge to assemble all the information for FM use at the end of the project.
Our broad understanding of LOD is more of a phasing issue where the amount of known information increases from LOD 300 to 500. The graphical detail of the elements typically does not differ throughout the modeling cycles. This is in part due to available element libraries and increased computer power. Simplification of elements if readily available is not really necessary. Thus, the main difference is the content and attributes within the model.
A general misconception is that you will end up with LOD 500 model by default as you have been continuously updating during construction. This is hardly the case — if the objective is not clear at the beginning or modeling critical information and features may be excluded and this would mean additional man-hours and costs at the end of the project to rectify the models.
Organization and Processes
Projects with BIM requirements need to be organized where the engineering team on-site is staffed with BIM coordinators embedded with the discipline managers involved in coordination with additional staff on hand for modeling. The BIM effort should not be set as a separate entity. With the volume of information generated through BIM and delivery expectations it may be necessary to include a dedicated information manager.
The typical workflow for modeling and coordination during construction involves a continuous cycle of model updates based on new information or changes due to coordination and design variations. Each change may require updating the pre-engineering documents within the BEP, including the LOD matrix, element attribute tables, system tables, etc.
BIM coordination meetings during construction are generally conducted weekly with relevant stakeholders in attendance. The following figure shows the weekly flow of modeling and coordination and approvals for shop drawings.
Modeling does not end with at the completion of a project. Operated facilities continuously evolve. BIM models need to be maintained to reflect current conditions. Changed equipment, room assignments, and so forth need to be updated in the models. This information can flow from site to the CMMS or Asset Management database at certain intervals depending on the criticality of the facility or system. The following figure shows the exchange of information and workflow between the operator and integrator to maintain the content of the BIM models and integration with FM digital infrastructure.
BIM models are inherently structured — in Revit we start out with the predefined categories of families and further define the types of family elements. This organization in model may not be consistent with the intended way you would organize your asset registry (management database). To align the data with a COBie-like structure, we also identify additional important family type parameters used to identify elements:
- Type Name
- Type Description
- Omniclass Number
- Omniclass Title
With the family structure and types defined a model would have several hundred instances of an element. This is where all the modeling effort goes — placing all the elements in the right location. Each instance of element will have unique properties that need to be defined for the asset registry. Here are additional important instance parameters used to identify element instances:
- Instance Name
- Instance Description
- Room Number
- Room Name
- System Code
- Subsystem Code
- Serial Number
As mentioned the organization within the BIM models may not be consistent with the organization of the asset registry. Facility and Asset Management may approach data different than what is set-up from the BIM models during the Design and Construction phases. For example, an AHU (Air Handling Unit) unit will be defined as different type within the BIM model — whether the unit is horizontal or vertical or even if it is single or double story. But from a Facilities or Asset Management point of view — the equipment has a fan and filter, depending whether it is large or small it will be identified as an AHU or FCU (Fan Coil Unit). It is very important to have the BIM model authored for FM use to be setup accordingly. Otherwise another layer of mapping of different types between the BIM models and FM platform will be required.
Element tagging is one of the main unique mechanism that we can use to link elements between the BIM models and FM infrastructure. Multiple tags exist for multiple purposes. There are several types of unique identifiers that can be used together to may be necessary to define or capture as attribute information within BIM models:
- Barcode tag numbers
- Equipment serial numbers
- As-built/shop drawing schedule mark
- Object ID compiled of several levels of coding
- GUID tags
- Classification Number: Omniclass [Masterformat, Uniformat] (US), Uniclass (UK), NL-SfB (NL), CoClass (SWE), etc.
While there are many ways to tag elements, it is critical to identify the basis for integrating the BIM and FM infrastructure. The client/operator needs to define this within their BEP and establish QA/QC procedures to ensure the accuracy of tagging in the model.
Several levels of information can be used to assemble element tags. Though long tags with too much information is not convenient. Human decipherable concise tags with the minimum number of layers that ensure each tag will be unique for each element is ideal.
Dispersed facilities like airports with several different buildings across a wide area should take into consideration not only maintainable assets, but also areas, zones, and roads which also need to be maintained and thus need their own unique identifying tag. This is useful to assign non-asset work orders, so everything including a roadside curb is an asset.
Tagging schemes need to take into account the need to track location independent assets or assets that may be relocated, decommissioned, and later recommissioned. Tracking the lifecycle of an asset without the proper tagging element management, deleting any element from the model will cause deleting all its history.
Room, space, and zone definitions are important for operations and asset management. We would like to know where assets are located. Typically, rooms are defined by the volume enclosing the room layout from the structural slab level to the upper structural slab soffit. This is to ensure all elements in the room including the mechanical equipment above suspended ceilings are captured. Large mezzanines may need to be separated vertically to emphasize equipment at high locations requiring special access.
Room and space identification in facilities are ever changing: during construction and at the beginning of operations all areas may be renumbered based on necessity. Room schedules need to be managed specifically before extracting data for FM. Similar to element tagging, space assignment must be rigorously checked through a QA/QC process defined in the BEP to prevent any faulty information.
Assets defining the several systems are extremely useful for operators, for instance to track the all ductwork routing from a selected grill to the AHU. Tagging systems across the multiple BIM models require tagging to manage systems. Naming of the systems shall also be done by consulting with the operating FM staff.
Defining systems having an enormous number of members is a challenge in complex facilities. Additionally, one equipment in a system will generally be a part of more than one system. All these systems should be defined in reference to a characteristic base equipment such as the main pump or AHU.
It is practical to have the visual 3D models with the systems defined, such as the HVAC systems, or the Fire Fighting system, where FM staff can easily visualize the nearest shut-off valve of a particular zone from the model. This may not be critical for a midsized project, but for a terminal building nearly a million square meters with more than 200 wet alarm valves, it is critical information during emergencies.
Daniel Kazado is a mechanical engineer with experience on more than 18 large airport projects. He is currently at ProCS Engineering as managing partner & BIM consultant. In the last 10 years, he’s gained extensive know-how with BIM and its use on large scale projects from design and construction to operations. His success with large scale projects lies in implementing the MEP Services using BIM system with the highest beneficial use to increase the productivity in the project.
Ahmet Çıtıpıtıoğlu, Ph.D., P.E., has been involved in the design, construction, and technical operations of several high-performance facility structures, from nuclear power plants and airport terminals to high-rise buildings around the world. His experience with all phases of large projects gives him a unique perspective from the early phases of a project with knowledge of the needs of operation.
Want more? Read on by downloading the full class handout at AU online: Creating Intelligent Digital Built Environments.