With building information modeling (BIM) gaining steam as a facilities management tool, many owners are excited to commission this game-changing technology for their buildings. But requesting a model is much more complex than ordering furniture or recycling bins.
“You can have the best BIM, but without the foresight and planning, it’s not worth commissioning,” says Pete Zyskowski, director of technical services and a BIM consultant with Applied Software, a BIM services provider.
A BIM deliverable needs to be as unique as the building it represents. As the end user, you determine what your model includes and how detailed it should be. To guide you through commissioning, follow these steps to ensure your deliverable will meet your needs.
1) Determine the Big Picture
A clear focus for your model is the most important part of the commissioning process. The level of detail you need directly impacts scheduling and costs.
First identify how the model will support facilities management. BIM allows you to gain greater control over areas like energy spend, space planning, and asset management – which of these benefits are you looking for?
“One of the best things owners can do is educate themselves on what value can be extracted from BIM – looking at how it adds value to their business, creates efficiencies, and ultimately saves them money,” says Kyle Bernhardt, product line manager for Building Design Suite at Autodesk, a 3D software provider. “It’s those calculations that can really provide a successful process.”
Without a clear purpose, you may get a model that doesn’t support your end goals. “Asking for just BIM is like asking a builder to just build a home. There’s so much more information that needs to be discussed,” says Mark Petrucci, an application specialist with Applied Software.
Because BIM is only starting to emerge on the operations side, you can’t use the same model that was created during design, otherwise it will be saturated with data unrelated to facilities management.
“Focus on the ‘I’ in BIM,” advises Aniruddha Deodhar, program manager of AEC Sustainability for Autodesk. “If all you have is a box, a wire 3D frame, it’s not as compelling. The more rich in content your BIM is, the more useful and valuable it is downstream for maintenance and operations.”
After determining the model’s scope, be ready to provide background data to the design team. If you are commissioning for energy management, you can help the contractor gather known data that will populate the model.
“In terms of energy analysis, the more figures an owner can offer the better,” recommends Deodhar. “Provide information about the mechanical systems, occupancy, building schedule, utility bills, rough estimates of floor-to-ceiling heights, and glazing percentages.”
Make sure these figures are as accurate as possible. If you cut corners with off-hand calculations or benchmarking, you’ll compromise the integrity of the model.
“Owners will try to use this information to save on costs but it ends up costing them more in the long run when they have to rectify or recreate a flawed model,” Deodhar warns.
2) Select a Scanning Option
How detailed your model is typically defines the methods used for reality capture, but there are several options available that meet different budget parameters:
- Measuring tape and wheel
- 2D architectural drawings (plan and scale)
- Laser scanning
- Photogrammetry
- Geospatial information gathering
A measuring tape and wheel have long been a standby in the industry. It’s a cost-effective option that doesn’t require complex technology and is ideal for simple spaces. These manually gathered dimensions are turned into a 2D architectural plan, which is easily converted into 3D, says Birgitta Foster, assisting director of the buildingSMARTalliance, an organization that promotes BIM. Owners with these drawings already in place have a leg up over those starting from scratch.
Owners should note that the accuracy of measuring tape and CAD drawings isn’t as strong as other reality capture options. For example, measurement methods differ – do you start a measure from the center of a room, a corner, or a wall? Are you measuring for gross square footage, net square feet, or rentable square feet?
Existing 2D plans also suffer from the same inconsistencies as blueprints – they can be inaccurate or out of date. Use laser scanning to confirm the reliability of CAD plans or bypass architectural drawings altogether.
“Laser scanning is the best possible method to capture the existing state in a 3D form,” recommends Bernhardt. “What you end up with once you aggregate multiple scans into a single point cloud is the 3D representation of that building. Anything that can be seen by the scanner is captured into hundreds of millions of data points. With the amazing computing power that’s brought to bear across the various technologies around laser scanning, it can deliver a remarkably real-life experience.”
While this method comes with a higher price tag, scanning affords a level of detail that cannot be matched by more traditional methods.
“From that high detail point cloud, it can be used as a modeling reference for the authoring of BIM elements,” Bernhardt continues. “You can very accurately and quickly trace walls, windows, and piping because you have a reference that is the real thing – in some cases down to a 7-millimeter level of detail.”
In fact, modeling technology has evolved to the point where it can distinguish between different types of systems. “You can bring the scan data into the software and it’s intelligent enough to recognize a pipe is a pipe, a wall is a wall, and so on. If it doesn’t know what it is, it won’t try to model it,” explains Foster.
The good news to an owner concerned about costs is that you can use any combination of reality capture methods (see sidebar on page 30). This is also a smart move if you have a wide variety of areas to document.
“An owner may determine that something as basic as a gymnasium does not require scanning because he only needs the dimensions of the four walls,” says Neil Parker, director of business development for EcoDomus, Inc, a BIM services provider. “With a boiler room, scanning may be the better choice because of all of the equipment that needs to be documented.”
3) Set Aside Time
The complexity of your model also impacts how much time it takes to create it. Most capture options take anywhere from an afternoon to a few days. Once the data is collected, a basic model can take a designer half a week to populate, while a fully integrated version will take much longer.
“It’s very difficult to generalize the amount of time it will take because it is extremely influenced by how complete you want the model to be,” says Bernhardt. “If you’re only looking for the envelope, you can model that in a number of days. If you want to go beyond the exterior and have accurate renditions of interior partitions, glazing, doors, and ductwork, it could be on the order of weeks, if not months.”
The size and age of your building are also factors. A one-story school takes less time than a 20-story high-rise. The older the building, the more complex it can be to model because of changes over time, says Zyskowski.
As your building undergoes reality capture, make sure your staff and occupants are aware of the extra contractors coming in. Employees may need to be displaced for an afternoon if after-hours documentation isn’t an option.
4) Vet Your Designer
Your goals for BIM also dictate who you need to bring on board. “The service provider or firm that generates these models is the single biggest factor for a project being delivered on time and on budget,” Bernhardt explains.
If you have a standing AEC firm you work with, ask whether they offer BIM services. An established relationship is ideal, particularly with the amount of communication required.
“BIM isn’t so much about the technology – that’s been around for 20 to 30 years,” says Mieczyslaw Boryslawski, co-founder of EcoDomus, Inc. “It’s about the collaborative effort between the different players.”
If your firm can’t meet your needs, select a BIM provider that has a proven track record with deliverables. Though the surveying industry has been around for decades, BIM is a new arrival and not all businesses have fully adopted the technology.
Request to see a project portfolio from a prospective firm, focusing on quality rather than quantity. “I’ve asked providers to share with me what their deliverable would be so I can understand if it’s sufficient for my needs or not,” Foster says.
Also ask about how they communicate with owners, whether they have their own scanning equipment or contract the service out, and if they can provide ongoing BIM assistance after the model is created.
“You want to make sure you’re working with a team who understands what your end goal is,” recommends Parker. “If your end goal is to create a model for a renovation project, you want to select a firm that has an eye toward renovation. Same with facilities management or new construction.”
5) Justify the Costs
Owners need to view BIM as an investment – the upfront cost to develop a model is typically countered by the efficiencies you gain.
Establishing ROI is tricky because the benefits of BIM vary so widely. How do you put a price tag on establishing consistency throughout multiple properties, supporting sustainability initiatives more efficiently, or gaining better control over energy spend?
“A highly detailed model is a costly proposition,” says Bernhardt. “But if you have clearly defined needs, you get value out of that level of detail and the cost will be warranted.”
Jennie Morton ([email protected]) is associate editor of BUILDINGS.
