Getting Mechanical Insulation into a Building Information Model

September 1, 2010

Though things are beginning to change, today we still need to start an article about a building information model (BIM) by defining it: a digital representation of physical and functional characteristics of a facility. A BIM serves as a shared knowledge resource for information about a facility, forming a reliable basis for decisions during its life cycle from inception onward. This definition was included in the United States National BIM Standard™ Version 1, Part 1, which was issued in January 2008.

While well over 50 percent of the industry now claims to use BIM, there are many quality levels of the BIMs in use today. Some firms are using BIM terminology for marketing purposes; others adopt BIM only for geometry; while truly transformed organizations have changed the way they do business and are implementing the full information and transformational aspects of BIM.

A BIM should be used throughout the life of a facility, from earliest concept through demolition and beyond. It should be the complete information record of everything that is included and occurs throughout that facility’s life. A few projects have embraced this cradle-to-grave approach, but they are still rare. However, this will not be the case for long, because many owners are awakening to the fact that using a BIM to manage the information in their facility can help them control costs far better and ensure that the facility provides its function at the expected cost throughout its life.

There are two major principles that, if applied, will guide your use of BIM in a project and help sustain the model throughout the life of the facility. The first is to gather information only once, at the point of creation of the information. Data should be entered into the model when it is created. From that point on, the information is used and re-used for various analysis tasks but is never re-collected. The second principle is to build the facility virtually first and, once all the issues are worked out, build it physically from the model. Having a visual as well as the embedded data in the model of the building will help the owner understand how to operate the facility. It will also allow the designer to see how the systems will function during the facility’s life in all situations.

For example, thermal and environmental considerations can be modeled to include heating and cooling, natural ventilation, daylighting, acoustical transmission, and many other conditions. Every player on the construction team also participates in this effort—essentially performing the same function they always have, just earlier and more collaboratively—prior to construction starting. The BIM should be as complete as possible to include as many details as are realistic, such as thickness of equipment, piping, and ductwork insulation. By incorporating the insulation depth, adequate room can be provided for proper installation, eliminating the current issue of compromising quality due to lack of clearance. Approaching the construction this way will ensure the owner has a true as-built facility when completed, and the analysis and simulation of the facility before it was built can be validated on a continual basis, ensuring that the performance standards are maintained.

BIM can help ensure the facility is as green as it can be, addressing environmental, sustainability, and security concerns without sacrificing occupant comfort. In addition, care must be taken to ensure that the facility is constructible and maintainable. This author recently heard of an example where a donor provided a financial gift to build a complex of facilities, with a stipulation that the facilities were to be sustainable for more than 100 years in a high-risk seismic zone. The team used BIM to design the structural system virtually so it could be assembled quickly in the field and fabrication of wall slabs could begin while the foundation and structural frame were being built. While the structural contractor initially expected the process to take significantly longer, assembly actually turned out to be much faster than anticipated. In the end, the approach saved time and money—plus, the heightened structural requirements for the seismic considerations added no additional expense over traditional methods of construction.

There is a lot of discussion as to how complete a BIM should be. While one could potentially model down to each screw and nail, in most cases this would far exceed the level of common sense. However, if a BIM is too austere, then the analysis will not be accurate, nor will constructability and scheduling be realistic.

Therefore, it is commonly accepted that all contractors and sub-contractors should be brought into the collaborative process and determine in pre-planning how deeply they need to be included in the model or, more accurately, what portion of their effort needs to be modeled.

As the Associated General Contractors of America (AGC) now stipulates, if someone’s work is not represented in the BIM, then that activity needs to take place after everyone else has completed his or her work. Hence, it might be important for subcontractors to include the conduit they need to run cable, but not the cable or devices to be installed in final fit out. This could address insulation on piping as well as all other uses of insulation, including walls and ceilings. Insulation should be included to work out clearances and energy usage and simulate various operating conditions.

The industry is still at the very early stages of implementing BIMs, and many issues remain. However, the value appears to be so significant that this author believes profound change will quickly come to the industry. BIM is a catalyst for the industry to make a significant change in thinking about how we do business. It should allow improved productivity and achieve new heights in energy and water management, all while delivering cost-effective and sustainable facilities for the duration of their existence.

Indeed, not all contracting methods lend themselves to the optimum implementation of BIM. Adjustments will need to be made to the way owners do business and how they ask for information. There are many new contracting alternatives being tested; some will emerge as successful, while others will fade into the past.

Change does not come easily to our industry (as is likely true for most industries). In the words of Peter Senge in the book Fifth Discipline, “People seek change, but don’t want to be changed.” Therefore, we need to keep the mood collaborative throughout the industry and with the owners. Members of the architecture, engineering, and construction industry have the opportunity to change themselves under their rules and use savings to make improvements and preserve profits. If the industry does not act and the owner catches on to the opportunity and takes on more of the risk of change, then the owners will mandate the change, and it will not be as desirable to the practitioner because the savings will manifest themselves in lower fees.

Just because the only tool one has is a hammer, it does not mean every fastener is a nail. This author urges you to get involved now and become a member of the buildingSMART alliance as we work to create open BIM standards that will be the basis for collaboration. BIM standards are in your best interests because they will ensure that interoperability of information exists and that you will have the most flexibility to choose the tool that best meets your needs.

The alliance needs you to become involved as a subject matter expert in the application and use of insulation, so you can ensure your interests are represented as the process moves forward. No one else can represent those needs. It can be accomplished on an individual basis or leveraged through the activities of the National Insulation Association. In any event, you need to ensure your voice is heard as the industry moves forward.
The change is coming. The time to act is now.