TBC

TBC

Making Buildings Work Better

The Units of Performance

People spend a lot of money on new buildings and often don’t get the performance they expect and deserve. As a commissioning authority, I can confirm that poor performance often stems from poor communication. Ambiguity, in particular, leads to assumptions which, let’s face it, are often wrong.

If we can improve communication, we can reduce the number of issues that occur, having a very real and positive impact to health and safety, comfort and operational costs (most noticeably smaller energy bills).

From Design to Operation

Mechanical designers use numbers and units to communicate the types and sizes of devices and sensors to be installed in a building. These decisions impact construction costs, capacities, control stability and operational efficiently. Designers also write sequences of operation to clarify how systems will be configured and programmed, which establishes appropriate limits and setpoints that can have an extremely large impact on operational performance.

If a contractor isn’t provided with enough information to implement a design correctly, should we really expect a designer’s intentions to be met?

In modern building automation systems (BAS), numbers are actually communicated with the use of electrical signals (in volts, milliamps, resistance or digital communication). As sensors and control devices can usually be selected or configured to act differently for the same electrical signal, people can’t make sense of the electrical signals until they have been translated into different numbers with more descriptive units (like airflow expressed in cfm). When units don’t get properly assigned—or even worse, when translation never occurs (ex: valve command expressed in volts), it gets much harder for building operators and engineers to understand how things are operating and to properly troubleshoot problems.

If a contractor implements an ambiguous design as documented or makes wrong assumptions for one or more pieces that were unclear, should we expect building operations and maintenance staff to fully understand the installed systems, effectively troubleshoot issues and keep a building running at peak performance?

What is a Unit?

When we deal with numbers, ‘units’ help provide a standard quantity to compare against—basically providing more information that ensures people are speaking the same language with regards to the meaning of a value. A size of a man who weighs 170 has very different meaning if measured in pounds or kilograms.

Numbers with missing or ambiguous units are one common source of confusion in buildings that are particularly easy to address. When these problems occur, an experienced person can usually read between the lines, but we should expect our design and construction teams to provide a professional-level effort to make sure bad assumptions are minimized.

Percentage is a ‘Quasi Unit’

Percentage takes the role of a unit, but still leaves room for interpretation. I call this a ‘quasi unit’.

Valve and damper positions are usually expressed in percent but what exactly is that communicating? For these kinds of devices, percentage usually refers to ‘% open’ but there are still many cases where they are actually programmed as ‘% closed’ or where the whole ‘open’/’closed’ concept simply doesn’t apply. The position of a 3-way valve could refer to a ‘percentage bypassed’ or ‘percentage recirculated’ but this is almost never clarified. When the intent isn’t clear, the likelihood of costly mistakes (like simultaneous heating and cooling) increases.

VFD speeds are also typically expressed by designers and manufacturers in the units of percent, but industry hasn’t come to agreement about whether this percentage is based on the high limit, controllable range or electric distribution frequency. Each of these strategies results in different actual speeds for the same signal. The table below illustrates how we’re not always speaking the same language when we communicate speed in percent.

Speed Signal (%) VFD Frequency (Hz)
(based on % of high limit) (based on % of controllable range) (based on % of elec distribution frequency)
0% 0 12 0
50% 45 41 30
100% 70 70 60

*Assuming VFD low limit set to 12 Hz, high limit at 70 Hz, and elec frequency of 60 Hz

This is more important than it seems. If a designer provides a sequence that asks for a fan to control down to 0% (presumably assuming % is based on a controllable range), the selected method could put the motor at risk of premature failure by operating at speeds where heat can’t be properly dissipated. The energy efficiency of different strategies can also vary significantly.

What’s the solution?

Improving performance has to start with a well-documented design. Reduce the number of bad assumptions by insisting that designers and contractors communicate more effectively. Make sure they consistently use units on numbers to fully communicate meaning.

Avoid the use of ‘quasi units’. If percent or another ambiguous unit is needed, ask for additional words to fully clarify what is really meant.

If the meaning is still unclear, make sure clarification is received early on… before equipment gets ordered and changes become difficult and costly.

Prove you’ve gotten what you asked for and what the designer intended. If you aren’t already using it, commissioning is a great way to help catch issues early, minimize risks to performance and maximize project success.

Benson headshotMr. Benson holds a degree in electrical engineering and is skilled in high-performance building design and control. He has a unique blend of experience with engineering, controls programming and fault detection. With this experience, he is able to bridge critical gaps that typically exist between design, implementation and ongoing performance. His work in new buildings includes fundamental and enhanced commissioning, measurement and verification (M&V) and facilitating energy-efficiency utility incentives. He is also adept in existing building services such as building performance assessments (including ASHRAE energy audits), existing building commissioning and HVAC controls upgrades. He consistently achieves significant energy savings and improvements to comfort from implementation of recommendations.

Is There Such a Thing as Too Much Attention to Detail?

too-much-information.jpg

by Ray Dodd

Our core business is commissioning large commercial and industrial buildings. What that means in simple terms is that we strive to make sure that, once constructed, the building performs as it was designed.

We are often accused by people with a more traditional view (before iPads) of creating pointless paperwork, being too detailed, stalling the project and adding an unnecessary layer of cost.

Unfortunately many contractors are focused on making their substantial completion date so they can pull off the job (stop spending money), and the owner can open the doors for business. If there are issues – we can deal with them later.

One situation we encounter frequently is being asked to skip the step of requiring that our checklists are completely filled out before we begin testing. The idea is to streamline the process. It NEVER works. The purpose of the checklists is to determine if the project is ready to be tested. We methodically test each system – starting with the ones that all the other ones are dependent on. We test systems – not just equipment. If the equipment works, but the interdependent parts are not finished, the whole process fails.

Before I was involved in commissioning I owned a heating and air-conditioning service business. After years of fixing systems I could point out what was wrong just by observation with a pretty good accuracy rate. When I started working for a company commissioning systems I too thought all that paperwork was unnecessary. But over time I changed my mind. With accelerated schedules and direct digital control, making sure that every single thing functions the way it is supposed to is a very complex job that requires great attention to detail.

On one of my first commissioning jobs we tested an emergency power system. We shut the main power off, timed how fast the transfer switch brought on the generator, and then looked around to make sure the emergency lights and fire alarm worked. Not much to it – a two-page test. My mentor at the time didn’t want to get too deep into the details.

Today, we have a 36-page document (authored by our electrical engineering team) just for testing the generator. We test all the parts of the emergency power system separately and then together – what’s called an integrated systems test. After all that is complete, we execute a final Pull-the-Plug-Test to make sure that everything that is supposed happen when the power goes down happens and then everything goes back to normal when power is restored. LOTS of attention to detail.

As the old saying goes: The devil is in the details. If you get the details right, the project is a success, you meet your goals, and you can move onto something else and stop spending money going back on warranty calls. Your customer is satisfied and is likely to call you back for the next project.

So I pose the question: Is there such a thing as too much attention to detail?

Ray_Dodd_CSERay Dodd, P.E., LEED AP, CxA is the President of Total Building Commissioning, Inc. in Salt Lake City, Utah. Mr. Dodd has been the owner of an HVAC service company, worked as a consulting engineer, and directed the engineering group for a large national mechanical design/ build company. Overall, Mr. Dodd has over 25 years experience in the design, construction, service, and commissioning of commercial, industrial, institutional, and high technology mechanical facilities systems and is frequently called upon as an expert witness providing easy-to-understand analysis to non-technical participants. He has a Bachelor of Science degree in mechanical engineering, a LEED AP, is a registered Commissioning Professional through AGC, and he is a registered professional engineer in Utah and Colorado.

Are Building Commissioning Agents simply “The Quality Police”?

by Ray Dodd

When I first started my career as a building commissioning agent (I had been a design engineer for 15 years before that) we were viewed by the contractors as the quality police: clipboard in hand, jotting down everything they did WRONG! From the first commissioning kick-off meeting I attended (the let’s get-to-know-you meeting) it was a contentious relationship. This was not what I had envisioned at all.

I had just come from a nine-year stint working for a large mechanical design/build contractor. We did everything in-house: sheet metal, pipe fitting, controls, service and engineering. When our people said they were ready to close-out the job there was no reason not to believe them. They were excellent, hardworking technicians. Yet our warranty costs far exceeded what we had budgeted, and our service trucks were a familiar sight in completed building parking lots long after we had pulled off the job. Clearly something was wrong.

After much discussion, it was decided that we should commission our own jobs. Using a standard commissioning protocol we set up a system and tasked each engineer to test the function of every system they designed. Within the first year we reduced our warranty costs by 70%!

We never uncovered a pattern of deceit or incompetence. What we learned was that these projects, especially with the increasing use of digital controls, were complex. The intersection of different trades, engineering disciplines, accelerated schedules and conflicting agendas required somebody to help the project achieve the intent of the designers. Since we were all on the same team our job as the building commissioning agent was to assure the success of the project for our company and the owner alike.

Today, as a third-party commissioning provider we have kept the same philosophy. We actively work with the contractors and engineers to reinforce the idea that we are dedicated to their success, and not interested in just pointing out flaws. It works. Over time we have created a team dynamic with many large contractors because they know that having us on their team assures a successful, more profitable project for them. For us, providing measurable value for every stakeholder in the project is a much better job than being the quality police.

Ray Dodd, P.E., LEED AP, CxA is the President of Total Building Commissioning, Inc. in Salt Lake City, Utah. Mr. Dodd has been the owner of an HVAC service company, worked as a consulting engineer, and directed the engineering group for a large national mechanical design/ build company. Overall, Mr. Dodd has over 25 years experience in the design, construction, service, and commissioning of commercial, industrial, institutional, and high technology mechanical facilities systems and is frequently called upon as an expert witness providing easy-to-understand analysis to non-technical participants. He has a Bachelor of Science degree in mechanical engineering, a LEED AP, is a registered Commissioning Professional through AGC, and he is a registered professional engineer in Utah and Colorado.

Commissioning is Not an Entry Level Job

by Ray Dodd

Look up “commissioning” in the dictionary and one entry you’ll find says: “To put (a ship) into active service.”

The term: Commissioning had its start in the shake-out of large ships, and later airplanes and industrial facilities such as refineries. The idea was to run a machine or process through its paces and work out the bugs before putting it into service.

This task was typically taken on by the most senior staff members. They had risen through the ranks and worked many jobs throughout the organization, so they had a global view of the design, building, and maintenance challenges of the machine or process.

The days of working in one factory or ship yard for a whole career has passed, but the concept — as it relates to commissioning — is still as viable as ever.

Commissioning buildings requires a unique skill set. You need to understand the very different yet integral points of view of the designers, builders, maintenance staff and owners. You need to understand of the function of the equipment you are commissioning and how it all ties together as a system, reacting to a multitude of inputs. Finally, in building commissioning, different trades – mechanical, electrical, fire/life safety and technology all interface to produce a safe building that works as the designers intended it to. As a commissioning agent, you need to speak the language of each trade and intimately understand that interface.

Being a commissioning authority is not an entry-level job – even for those armed with a brand-new shiny engineering degree. It takes experience and exposure to the many facets of the building construction business. And that takes time.

Ray_Dodd_CSERay Dodd, P.E., LEED AP, CxA is the President of Total Building Commissioning, Inc. in Salt Lake City, Utah. Mr. Dodd has been the owner of an HVAC service company, worked as a consulting engineer, and directed the engineering group for a large national mechanical design/ build company. Overall, Mr. Dodd has over 25 years experience in the design, construction, service, and commissioning of commercial, industrial, institutional, and high technology mechanical facilities systems and is frequently called upon as an expert witness providing easy-to-understand analysis to non-technical participants. He has a Bachelor of Science degree in mechanical engineering, a LEED AP, is a registered Commissioning Professional through AGC, and he is a registered professional engineer in Utah and Colorado.

Standby for Changes: Required Commissioning for Commercial Mechanical and Lighting Systems per the IECC 2012 Code

The 2012 International Energy Code is now being adopted by municipalities throughout the United States and contains new requirements for building systems commissioning.

Commissioning provides the building owner, designers and builders with risk mitigation by assuring that the systems function as designed. Commissioning also reduces RFIs, warranty issues, maintenance and construction issues as well as schedule creep due to lack of coordination by trades.

Until now, building commissioning has been prescribed for projects where non-conformance is an unacceptable risk, and for projects pursuing LEED (Leadership in Energy and Environmental Design) where building systems commissioning is a prerequisite for certification.

This new commissioning requirement is an important step to ensuring that buildings are designed, constructed and operate according to the owner’s needs, however, it’s a big change for owners and contractors if they aren’t aware of the new requirements and how they will affect projects with respect to cost, schedule, and participation.

With these new standards, the demand for commissioning in buildings will intensify. Significant changes in the code now require commissioning of the HVAC equipment, lighting controls, economizers and control systems of nearly all commercial projects with 40 tons of cooling or 50 tons of heating (680 MBTU of heating).

Requirements specific to the new 2012 code can be found in Section C408.1 of the IECC including commissioning of the building mechanical systems in Section C403 and lighting systems in Section C405. Some highlights include:

  • A detailed commissioning plan developed by a registered professional engineer that includes pieces of equipment; an operations and maintenance manual; and descriptions of systems adjusting and balancing.
  • HVAC systems require test and balance (TAB)
    • Air and water flow rates measured and adjusted to deliver final flow rates within tolerances in product specifications
    • Test and balance activities to include air system and hydronic system balancing
    • Each supply air outlet and zone terminal device equipped with means for air balancing per Chapter 6 of the IMC
    • Individual hydronic heating and cooling coils equipped with means for balancing and measuring flow
  • Functional performance testing to include all modes and sequence of operation, including full-load, part-load and emergency conditions.
  • HVAC control systems to be tested to document that control devices, components, equipment, and systems are calibrated, adjusted and operate in accordance with approved plans and specifications.
  • Sequences of operation to be functionally tested to document that they operate in accordance with approved plans and specifications.
  • Buildings or portions of buildings can’t pass final mechanical inspection until the code official has received a letter of transmittal from the building owner acknowledging the building owner has received the Preliminary Commissioning Report.

Is your Commissioning Authority and Firm certified?

Professional certifications and degrees are clear marks of competency in the architecture, engineering and constructions fields. However, when it comes to commissioning, an individual cannot obtain a degree in building commissioning and instead clients must depend on their commissioning agents to bring to the table a mix of job experience and industry recognized certifications. There are several certifications that clients seeking commissioning authorities can look to in order to ensure requisite knowledge and understanding of the building commissioning process.

Certified Commissioning Authority (CxA) from the AABC Commissioning Group

CxA certification is required for all government and military-related projects. Additionally, many industry clients, such as the healthcare sector, require certification.

This certification requires an examination not only an examination but the company must also be an independent certified commissioning firm. In addition to the examination, the commissioning authority must provide references and submit documentation on at least three projects. The certification is reviewed and renewed on annual basis to ensure the commissioning authority provides a quality-based service.

“The Certified Commissioning Authority designation allows clients everywhere to rely on professional credibility and dedication to providing the best in comprehensive services,” TBC Project Commissioning Authority Todd Watson,  LEED AP, CxA, QCxP, explains.

Accredited Qualified Commissioning Process Provider (QCxP) from The University of Wisconsin Madison

The QCxP provides a level of recognition for those who have acquired an understanding of the commissioning process through education and demonstrated a minimum level of understanding of the commissioning process through training and an examination.

Accredited Commissioning Process Technical Support Provider (CxTS) from The University of Wisconsin Madison

The CxTS highlights the skill and experience of individuals who have provided commissioning services primarily in select project stages, on small or limited scope projects, or who provide key technical support to commissioning activities. Applicants must provide documentation on two major or four smaller new construction or rehab projects or equivalent existing building projects, including letters of reference and pass the examination.

Owners and clients who seek out both commissioning expertise as well as industry recognized certifications from their certified commissioning professionals can rest assured that their high-performance, energy-efficient building will function as intended, every time.

Healthcare Commissioning Requirements for Certification

The popularity of building commissioning in the past ten years has increased dramatically largely due to the LEED (Leadership in Energy and Environmental Design) building certification program. The prescribed commissioning requirements for LEED were designed to validate that the energy consuming systems in the building–HVAC, lighting and domestic hot water–perform as designed. However, commissioning can deliver far more than an energy performance validation.

Commissioning provides the building owner, designers and builders with risk mitigation by reducing RFIs, warranty issues, maintenance and construction issues as well as schedule creep due to lack of coordination by trades. In specialized function facilities like state-of- the- art healthcare centers, the risk of critical systems failing to perform is unacceptable, thus commissioning is crucial to realizing the expected performance of the facility.

To that end, the Utah Department of Health Facilities Certification group has adopted, as of February 2012, the 2010 Guideline for Design and Construction of Health Care Facilities. In guideline section 1.2-8, commissioning is now required for the following systems:

  • HVAC
  • Electrical
  • Emergency Power
  • Nurse Call
  • Med Gas
  • Fire Protection/suppression
  • Telecom
  • Alarm/Security
  • Pressure relationships for Infectious Control

To Functionally Test or Not

There have been debates for years about what terms to use for the different commissioning tasks. One of those tasks is Functional Testing. There have been several suggestions for alternative terms. Below are my thoughts on some of the terms suggested to me. Read the rest of this entry »

Thinking Outside the Box

As commissioning authorities we are asked to think outside of the box, ask questions such as: what if? and why? to get people thinking and to try to avoid unforeseen problems. It’s like the graphic below, which I love. Can you connect 9 dots in a 3 x 3 square using only four lines and only going though each dot once?

Read the rest of this entry »

Presentation: Who Stole My High Performance Building?

I want to thank the Utah ASHRAE Chapter for inviting me to give my presentation called “Who Stole My High Performance Building?” on Friday December 3, 2010. It was a packed house with over 70 people in attendance. The audience participation and questions were great.  This presentation shares many of the lessons learned in the field and gives valuable feedback of how different designs are performing in the field. Read the rest of this entry »

About TBC

As a leader in the building commissioning industry, Total Building Commissioning (TBC) is a facility consulting firm that specializes in the commissioning of mechanical, electrical, controls and all other major building systems as well as LEED™ certification consulting.

Contact TBC

info@tbcxinc.com

Phone: 801-401-8401
Toll Free: 877-822-9462

324 South State Street, Suite 400
Salt Lake City, Utah, 84111