Engineering news

Building Commissioning

Three Key Myths

Our team of professionals can help to assure that your building will operate as intended when the job is complete. Many of the problems that we encounter during the commissioning process relate to the performance of systems in the building. Understanding how buildings operate and how each integral part affects the whole is critical in evaluating a building. Many systems may function properly on paper, but may not function so well when installed in the field. This may be due to shipping damage, improper or careless installation or many other factors. Discovering these deficiencies and correcting them on a proactive basis reduces the overall cost of operating and maintaining the building. This costs savings is achieved through energy efficiency, reduced liabilities, longer life cycles for systems and higher productivity. Many building owners look only at initial costs but this can be costly. Once the building is in operation, many of the problems which should have been detected, diagnosed and corrected during design and construction have become a major failure and may involve damaged building components, litigation, increased insurance costs, etc. Call us to discuss your commissioning needs. Our services include indoor air quality, HVAC systems, engineering, operational performance checks, infrared thermography and other services which can be developed to meet your needs.

For existing buildings, the commissioning process is just as important in establishing building performance and energy goals. Our process for commissioning existing buildings includes:

Thermography used to discover overheated pump motor due to misaligned shaft & poor electrical power connections

Commissioning is a quality-oriented process for achieving, verifying, and documenting that the performance of facility systems and assemblies meets defined objectives and criteria. The Commissioning Process begins at project inception during the Pre-Design Phase and continues for the life of the facility through the Occupancy and Operations Phase. During the Pre-Design Phase, the Owner’s Project Requirements (OPR) are determined and documented by the Commissioning Team, which includes the Owner, Commissioning Authority (CxA), design professionals, operation and maintenance personnel, occupants, and users. Throughout each phase of the project, deliverables (drawings, specifications, submittals, construction, training, documentation, etc.) are verified against the OPR. (ASHRAE Guideline 0-2005)

Building As a "Whole"

A Holistic Design Philosophy

The concept of "wholes" is not new. In 1926, Jan Christian Smuts, a South African Prime Minister and philosopher, coined the term "holism". He believed that there are no individual parts in nature, only patterns and arrangements that contribute to the whole. Buckminster Fuller also said back in 1969 while working on the space program: "Synergy is the only word in our language that means behavior of whole systems, unpredicted by the separately observed behaviors of the system's parts or any subassembly of the system's parts."

When commissioning a building in years past, much of the commissioning process and budget was focused on the operational performance of the HVAC systems. The HVAC system alone cannot be completely or functionally commissioned unless the "holistic" approach, used by the C.L.I. Group is adopted. It is becoming increasingly clear that the building envelope is an integral part of a commissioned building. Water & air control, building pressures and indoor air quality are all directly related to the economical operation and performance of a building. Our multi-disciplined team includes TAB professionals, IAQ professionals and building science experts that can put the pieces of the puzzle together. The building should operate as designed on all levels. Shortcomings in any of the mentioned systems can adversely affect all of the other systems in addition to creating problems of their own. In recent years "whole building commissioning" has come to the forefront of the commissioning process and has been extensively written about and adopted in many areas. Organizations such as N.I.B.S. and  ASHRAE are looking at standards for whole building design and commissioning. The image (left) shows significant and expensive damage in the wall of a classroom recently evaluated by C.L.I. Group. This expensive damage could have been prevented if the building had been properly commissioned when built.

The idea that all building problems and issues can be addressed through the HVAC systems is a costly idea for many building owners. The costs involved in the never ending adjustment, repair and replacement of HVAC systems and components is expensive enough. When you add that cost to the poor results achieved, the costs begin to rise even more. So why aren't the repairs and replacements working? Well, they may not be the problem. This is the main reason why using an independent third-party company to perform the assessment of the problem is the most cost effective answer. A third-party consulting firm does not have the financial bias that a specialty contractor has. Therefore an unbiased evaluation will look at all potential problems. To put this idea into perspective, imagine how many health problems would go undiagnosed with potentially catastrophic results if everyone chose only heart surgeons to diagnose their health concerns. What if your problem was cancer, liver failure or a brain disorder? This is similar to what many building owners do. They call their HVAC contractor to answer questions about all problems (e.g. comfort, moisture, energy costs, indoor air quality, etc.) and naturally the HVAC contractor finds that the HVAC system needs extensive repair and/or replacement. The building enclosure, building pressures, etc. are never evaluated.

The new ASHRAE Guideline 0-2005 addresses the total building commissioning process and NIBS Guideline 3 will soon be published which covers the building envelope. This effort shows the increasing awareness of commissioning buildings as a whole.

Total Building Commissioning (U.S. General Services Administration) Definition:
                                         
To assure a high standard of excellence, GSA utilizes a Total Building Commissioning Process. Total Building Commissioning is the Public Buildings Service’s (PBS) process for quality assurance in new construction and facility modernization. It is the process for achieving, validating and documenting that the performance of the total building and its systems meet the design intent and requirements of the owner.

For more information on our "Total Building Cx Philosophy" click here.

Because all building systems are integrated, a deficiency in one or more components can result in suboptimal operation and performance among other components. Remedying these deficiencies can result in a variety of benefits including:

Commissioning The Building Envelope for Moisture Management

Moisture control problems account for up to 80 percent of all associated premature wear expenditures made on built facilities. Although proper commissioning procedures have been noted to reduce the potential for approximately 70 percent of these claims, no standards exist for the control of moisture migration in building commissioning guidelines. The development of commissioning guidelines for the control of moisture migration involves quantifying, with a risk management approach, the performance thresholds that distinguish acceptable from unacceptable design. These criteria should define allowable threshold values regarding mold growth, corrosion, loss of structural strength, and indoor air quality. This report includes an introduction and brief history of building commissioning and the code regulations intended to address moisture in buildings, a description of the commissioning process as related to the building envelope in humidified buildings, and discussions of building humidification and the criteria and guidelines for commissioning humidified buildings. The guidelines explain the role of a building envelope commissioning agent, from early in the design phase, through construction, to assuring proper operation after occupancy. This process includes the use of performance modeling techniques to predict the envelope performance prior to completion. Establishing guidelines for the commissioning of humidification is an important step toward anticipating and preventing the conditions that may lead to moisture problems and related health effects and maintenance expenditures.

Commissioning for Humidified Buildings, Brian M. Deal, William Rose, and Scott E. Riley, USACERL Technical Report 99/03 November 1998

Evaluating Overall Building Enclosure Performance

In evaluating the performance of the building enclosure, we look at four key functions:

Evaluating these functions can be achieved through building mock-up, on-site testing, plan reviews and materials evaluations. It is our opinion, that building owner's that opt to have the enclosure commissioned will experience better across the board performance from the building. Benefits may include:

The status-quo building commissioning that we have all become accustomed to may not be providing the benefits that many owner's expect. The reason, in part is that current commissioning practices include only HVAC systems. This reduces the potential for meaningful commissioning and reduces opportunities for energy and equipment cost related savings. Building owner's need to be educated about the benefits of building enclosure commissioning. This is true for both new and existing buildings. To better understand commissioning and the benefits it can bring, an owner must first gain a better understanding of how systems of a building should act as a integrated system and NOT as independent systems.

C.L.I. Group has been involved in numerous projects that involved complaint's from building owners regarding comfort and energy costs. The owner's have often contacted us after unsuccessful attempts by other to correct the problems. What we have found in many cases, is that owner's intuitively contact their HVAC contractor when comfort problems arise. In many cases the answer they get is to increase current system capacity or to add new systems. What we have found is that while adding additional capacity or a new system may address the comfort complaints, there will be a substantial dollar penalty for such band-aid type fixes. We have also found, that in the majority of cases, no one has evaluated other potential remedies. We have often evaluated the building enclosure and found that there is excessive air leakage, poor thermal performance (thermal bridging) and other problems that affect building comfort and drain energy budgets. The fact is, that by correcting the envelope, we may be able to reduce capacity of HVAC systems and eliminate comfort complaints. The saving from correcting a building in this fashion will last throughout the life of the building. Much the same that adding HVAC capacity will increase operating expenses for the life of the building and may not completely address comfort complaints.

Retro-Commissioning

The Retro-commissioning process identifies low cost operational and maintenance improvements for existing buildings that typically payback in less than 1 year. Retro-commissioning primarily optimizes equipment and systems operation but can also be used to identify solutions to recurring operational problems.  The American Council for an Energy Efficient Economy (ACEEE) recently identified Retro-commissioning as the 2nd most effective energy saving process among 38 evaluated measures.

Retro-commissioning may identify capital improvements, however, its primary focus is on using diagnostic evaluation and testing to identify opportunities to optimize the building systems. Retro-commissioning identifies the opportunities to:

Retro-commissioning an existing building is much different than commissioning a new building. The systems, controls and methodologies may be similar, but there are several other considerations when commissioning an existing building. The first thing to consider is that in retro-commissioning a building, the designer, builder, etc. are probably no longer part of the process. This leaves more responsibility and liability on the CxA. The costs and time involved should be considered. A few other considerations for commissioning an existing building:

The questions above, as well as others must be answered before undertaking a retro-commissioning project. There should be a clear understanding between owner and CxA from the onset concerning which systems are to be commissioned and how they are to be commissioned. This prevent misunderstandings later in the process.

The Building Envelope in Retro-Commissioning

Airtightness and infiltration rate measurements in office and other commercial buildings have shown that these buildings can experience significant levels of air leakage. The energy impact of air leakage in U.S. office buildings was estimated based on the analysis of a set of 25 buildings used in previous studies of energy consumption. Each of these buildings represents a portion of the U.S. office building stock as of 1995. The energy impact of air leakage in each building was estimated by performing an hourly analysis over one year, with the infiltration rates varying linearly with the wind speed. The energy associated with each of the 25 buildings was then summed to estimate the national energy cost of air leakage. The results show that infiltration accounts for roughly 15% of the heating load in all office buildings nationwide, and a higher percentage in recently constructed buildings.

Source:

Implementing the Results of Ventilation Research. AIVC Conference, 16th. Proceedings. September 19-22, 1995, Palm Springs, CA, 379-391 pp, 1995.

A Failure to Communicate?

It is becoming increasingly clear that building commissioning today involves more than just numbers matching on a balancing report. Today's built environment is much more complex than it was 25 years ago and component parts play a more critical role in proper building operation and cost. Failing to commission any integral component of the whole building could leave your building vulnerable. Evaluating buildings over the last several years has changed our thinking on what it means to commission a building. In cases such as the church classroom shown above, simply balancing the HVAC system would not have discovered or corrected the cause for this major failure in the building envelope. In the noted building, not only was the building envelope in various stages of failure, the indoor air quality was suffering as a result of biological contaminants introduced into the indoor environment as a result of moisture issues which were discovered.

The above case is only one of many in which we have recently been involved. These cases emphasize the importance of addressing building commissioning with a "whole building" mentality. This takes a very specialized team of experts to get the job done right. The old school of thought when it comes to commissioning only the mechanical system is like maintaining your car by only putting gas in the tank. A building, like an automobile, must be maintained in it's entirety in order to achieve longevity and efficiency. In too many cases, contractors, architects and engineers call for commissioning of the HVAC system only. This is a problem when the building envelope is ignored. Remember, "In Order to Balance a System, It Must be Balance-Able". Not including the envelope in the commissioning process may make truly balancing the HVAC system unrealistic or impossible. The fact is, you must contain air before you can control it.

What is LEED®?

The Leadership in Energy and Environmental Design (LEED) Green Building Rating System™ is the nationally accepted benchmark for the design, construction, and operation of high performance green buildings. LEED gives building owners and operators the tools they need to have an immediate and measurable impact on their buildings’ performance. LEED promotes a whole-building approach to sustainability by recognizing performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection, and indoor environmental quality.

LEED provides a roadmap for measuring and documenting success for every building type and phase of a building lifecycle.

LEED-NC

LEED for New Construction and Major Renovations is a green building rating system that was designed to guide and distinguish high-performance commercial and institutional projects, with a focus on office buildings. LEED-NC has also been used on K-12 schools, multi-unit residential buildings, manufacturing plants, laboratories and many other building types.

LEED-EB

LEED for Existing Buildings maximizes operational efficiency while minimizing environmental impacts. It provides a recognized, performance-based benchmark for building owners and operators to measure operations, improvements and maintenance on a consistent scale. LEED for Existing Buildings is a road map for delivering economically profitable, environmentally responsible, healthy, productive places to live and work.

LEED-H

LEED for Homes is a voluntary rating system that promotes the design and construction of high performance "green" homes. A green home uses less energy, water, and natural resources; creates less waste; and is healthier and more comfortable for the occupants. Benefits of a LEED home include lower energy and water bills; reduced greenhouse gas emissions; and less exposure to mold, mildew and other indoor toxins. The net cost of owning a LEED home is comparable to that of owning a conventional home.

The LEED Rating System is the nationally recognized standard for green building. LEED certification recognizes and rewards builders for meeting the highest performance standards, and gives homeowners confidence that their home is durable, healthy, and environmentally friendly

LEED® Building Commissioning includes:

Energy Prerequisite 1: Fundamental building systems commissioning (required)

Energy Credit 3: Additional commissioning (1 point)

Primary Responsibilities Chart for LEED NC v2.2 - EA Prerequisite 1 and EA Credit 3

Commissioning is a critical component for any green/sustainable building project. Whether the goal is LEED certification, better indoor air quality or reducing your carbon footprint, TOTAL building commissioning can help you achieve those goals.

The Need for Residential Commissioning

The process of commissioning new and existing homes is becoming not only cost effective for builders, consumers and building departments, it should be considered by every party involved with residential buildings including real estate professionals. .

According to Dominion, natural gas prices rose 15% this winter and that fact alone makes commissioning attractive. For builders commissioning can be cost effective by providing documented quality control/assurance and reducing expensive callbacks. For consumers commissioning can assure that the home will perform as intended and allow for the resolution of any disputes before expensive litigation is involved. For real estate professionals an energy efficient home that performs as intended may qualify for an energy efficient mortgage allowing for the buyer to qualify for a larger mortgage based on the estimated energy savings over the mortgage term.

The C.L.I. Group, LLC commissioning program evaluates the home as a system as opposed to evaluating the building on a component basis. We understand that a building performs best when all systems work as a whole and the building should be designed and constructed with this factor in mind. Today, homes are built differently than in the past. Technology and materials have changed since the mid-1970’s in an effort to conserve energy. Homes are built tighter in an effort to achieve this goal. However, as the homes have been tightened, the incidence of moisture related and indoor air quality complaints has risen. Helping builders and consumers to understand why these problems are occurring and how to prevent them from occurring is our business. In most cases, the materials and technologies are correct but the approach to constructing the building and making the systems perform as a whole is where the problems begin.

It is our goal to see new materials and technologies utilized to their full potential so that building performance can achieve it’s intended purpose of providing a comfortable, energy efficient and environmentally friendly home while not escalating the cost of the home. This is achieved through education and by using a whole building commissioning process that assures quality and performance at a reasonable price. This is where our company has stepped out of the box of simply using a home energy rating. While a HERS rating is a good initial step in the process, there are additional items that should be addressed as part of an overall residential building commissioning program.

The commissioning procedures listed below are intended to be implemented at the design stage and follow through to the building occupancy. However, the process works well for existing homes by aiding in the development of cost effective retrofitting procedures that will increase the performance of the existing housing stock.

C.L.I. Residential Commissioning Program

Building Envelope

Air Distribution Systems

HVAC System

Building Pressures

Indoor Air Quality

Whole Building v. Component:

A substantial reason for these problems is that few houses are now built or retrofitted using formal design procedures, most are field assembled from a large number of components, and there is no consistent process to identify related energy and non-energy problems or to correct them. Solving the problems requires field performance evaluations of new and existing houses using appropriate and agreed upon procedures. Many procedural elements already exist in a fragmented environment; some are ready now to integrate into a new process called residential commissioning (Wray et al. 2000).

The fragmented environment in commissioning is the same environment that has become a problem in building. It is C.L.I. Groups goal to bridge that gap in Ohio to assure that everyone is on the same page. The result will be better buildings, less litigation, happier builders and happier consumers. The way we see it, it's a win/win proposal.

Publications

In addition to the partnerships below, we are ASHRAE Certified Commissioning Process Management Professionals (CPMP),  International Code Conference (ICC) Certified (Building, Mechanical, Plumbing & Electrical) and Energy Inspectors/Plans Examiners and Association of Energy Engineers Certified as Indoor Air Quality Technicians.

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