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Do You Trust the BIM Calculations Generated by Your Software?

Concept of worksite on technical drawing structure and construction

Technology has done wonders to streamline the intricacies of construction design and engineering. It’s so much easier to create a mechanical building design and to determine and assemble all the parts, connectors, and other manufacturer-specific content required to construct it using advanced BIM software. Nevertheless, a major factor for errors are BIM calculations, but why is that?

We can trust that the content assembled using BIM software will work together, thereby circumventing incompatibilities and clashes. With a good BIM solution – one that is regularly updated with changing manufacturer specifications, our expectations of a flawless M&E design are met.

That’s one important tight spot to overcome. Unfortunately, the same cannot be said of BIM-generated mechanical calculations. 

3 Keypoints of This Article

  • BIM Software's Calculation: Despite the capabilities of Building Information Management (BIM) software in streamlining construction design and ensuring component compatibility, the accuracy and reliability of BIM calculations remain questionable, prompting professionals to seek external verification.
  • CIBSE's Solution for Verification: BIM software packages that meet accuracy standard by CIBSE are awarded the Software Verification Assessment (SVA) logo, ensuring professionals of their accuracy and conformity to standards.
  • Trimble's CIBSE Verification Achievement: Demonstrating its commitment to precision and compliance, Trimble's Stabicad has become the pioneering software to receive CIBSE's independent certification for its mechanical and electrical calculations, covering a wide range of functionalities from heating and cooling to electrical systems.

Why We Need BIM Software Calculation Standards

The accuracy of your mechanical calculations is just as imperative as the compatibility of the design components and the origin of the data. Unfortunately, there’s no easy way to know if the calculations generated by your BIM software are correct or not, or even how they were achieved.

With so many downstream processes relying on these calculations, M&E designers and engineers are compelled to take extra steps to ensure they are precise and true to form. Pipe work sizing, for example, is derived from a complex computational result based on a series of nested variables, including flow, velocity, losses in straight and contiguous pipe runs, and individual fittings — each requiring its own calculation. If any one of these calculations is off, the result is rubbish.

To confirm calculation accuracy, designers seek verification outside of BIM software. Typically, validation is completed using either a trusted third-party software package or an engineering firm —and this validation step must be repeated each time BIM software is revised or updated. 

Not only are these steps time-consuming, why should you have to prove that BIM software does what it says it does? And, of course, it’s not just you who is repeatedly performing these checks. Every single M&E designer worth their salt, all around the globe, is doing the same verification process with each BIM software revision. Is this not a huge waste of time?

Cracking the BIM calculations code

The engineers at the UK’s most trusted building services institution, CIBSE, took on the task of putting a full stop to this inefficient approach. Two years in the making, CIBSE’s Society of Digital Engineers (SDE), along with the product management team from Trimble, developed a software verification assessment methodology that can reliably test whether BIM software calculations are correct and in accordance with CIBSE guidance. 

If a BIM software package successfully meets the requirements of this independent verification assessment, the software is certified by CIBSE, and a software verification assessment (SVA) logo is issued. 

Now, when you use BIM software that displays the SVA logo, you can trust that all BIM-generated calculations are correct and up to current standards. No more checking and rechecking. Redesign and rework, as well as project risk, are reduced. You can produce accurate M&E designs within shorter timeframes, increasing your overall productivity and efficiency. Perhaps best of all, you’ll have peace of mind knowing there are no gremlins hidden in the mix.

Trimble: First in the industry to achieve CIBSE verification for accurate BIM calculations

Trimble has long been synonymous with compliant BIM calculation services. With the digital evolution of seamless end-to-end building design and construction workflows, the need for precision is now greater than ever.  

So it is with pride that we announce that Stabicad is the first in the industry to have mechanical and electrical calculations independently certified by CIBSE.

These include:

  • Air systems
  • Heating and cooling water systems
  • Domestic water systems
  • Drainage systems
  • Electrical demand
  • Electrical systems: Cable sizing
  • Electrical systems: Protective devices

Watch the SVA session from Build2Perform 2022 for additional details.