By: Ed Iczkowski
Lately, Commissioning (Cx) has been the topic of discussion in the construction industry. The proponents swear by it while those opposed to it claim it is smoke and mirrors. Many building owners, developers, and design professionals are asking themselves why bring another consultant into the construction process and how can they afford the additional expense? The question that should be pondered is, can I afford not to Cx my next project?
The American Society of Heating, Refrigerating and Air-conditioning Engineers (ASHRAE) defines Cx as the process of ensuring systems are designed, installed, functionally tested, and capable of being operated and maintained to perform in conformity with the design intent. Cx is not merely a series of inspections. It is a systematic process that encourages quality workmanship, verifies correct system operation and maintainability, produces a trained operation and maintenance staff, and provides thorough documentation. The Cx Plan is developed, by the Commissioning Authority (CA), based on the owner’s needs and is project specific. Less sophisticated systems will require less rigorous Cx than more complex systems.
The current state of the construction industry has created the demand for Cx. Over the past decade, construction costs have risen, the design time has shrunk and the build schedule has been reduced so that nearly every project is a fast-track job. Current design fees have not risen proportionally with the cost of constructing a building. The Architect and the Design Engineers have no choice but to minimize or even eliminate services to stay competitive. In the not too distant past, the design team regularly attended construction meetings, promptly answered requests for information and performed field inspections. It is a rare occurrence, to see the design team on a construction site today. When the market will not bear fair and equitable fee increases, services must be reduced in order to remain competitive and profitable.
Paul C. Tseng, PE, CEM describes the traditional plan-spec-bid-build process as promotes finger pointing, generates expensive change orders, sacrifices quality in the name of the lowest price, and discourages creativity and innovation in the name of risk management. The Construction Manager (CM) was introduced to the construction process to more effectively coordinate the various construction trades, minimize owner expenditures and maintain the construction schedule. The typical build schedule has been reduced by nearly 25% forcing the CM to eliminate engineering review and system functionality inspections. The CM is typically rewarded for expediting the schedule; faster doesn’t equate to a superior product. The encouragement to accelerate the schedule leads to mistakes and poor workmanship which generally results in change orders leading to increased owner cost, contractor discord and virtual elimination of any form of teamwork.
The construction industry has experienced many new technological advances resulting in more affordable state of the art facilities. Nearly every new building utilizes Direct Digital Controls (DDC) whereas two decades ago this was cost prohibitive. With the technological advances comes the need for specialized installation crews. To produce more in less time, contractors have gone to an assembly line approach. One crew will hang the air-handling unit, another crew will install ductwork, another crew will install piping, another crew will install control components and another crew will install control wiring. It is not uncommon to have dozens of crews working on a single system. The primary goal of the installing contractor is to expedite the schedule by maximizing production.
The traditional common goal of the owner, design team, construction manager and the installing contractors is speed. Generally, expediting the schedule results in an early completion date, increased change orders and extended punch lists. When time is the only concern, quality suffers. The Cx process expedites the schedule, encourages quality workmanship, reduces or eliminates change orders and minimizes punch lists and project close out time. The Cx process is recommended to start in the conceptual design phase although it can start at any time during the project. The earlier the Cx process is started, the more benefits will be gained. Most owners that implement Cx for the first time begin during the construction phase. Once an owner has experienced the Cx process, they will use it again and generally implement it earlier in the project.
Cx is a four-phase process; design phase, construction phase, acceptance phase and post-acceptance phase. During the design phase, the owner’s design intent is developed and the CA develops the Cx Plan. The CA conducts reviews of the Construction Documents (CD) at 50% and 95% to verify that the CD comply with the owner’s design intent. The review will identify issues that are likely to result in change orders, schedule delays and system maintainability. The CA will prepare Cx specifications including the contractor’s responsibilities. The Cx fee, for a typical office building, during the design phase is 0.2 – 0.6% of the construction cost.
The CA reviews submittals, creates project specific checklists, develops an Operation & Maintenance program tailored to the owners needs and manages the CX process. The CA’s submittal review concentrates on design intent compliance, maintainability of the equipment and serviceability of the equipment comprising the system.
Project specific installation and start-up checklists are created by the CA. The CA will utilize the CD, manufacturer’s installation and maintenance manuals, and the CA’s construction experience to create meaningful punch-list style checklists. The checklists will incorporate the work of all trades responsible for the system installation and start-up. There maybe more than four different trades installing a VAV box and once a mistake is made, the trades following may very well compound the problem. The checklists curtail repeated mistakes and help to identify problems early. The CA will perform field verification of the checklists and maintains a deficiency and acceptance log or issues log.
The o&M program is being developed as the facility is being constructed. Some facilities have in-house personnel, others may sub-contract the service, while others may employ a combination of both. The O&M program must comply with the owner’s design intent and typically includes; staff training, well document manuals, operating procedures, maintenance schedules, spare parts lists and vendor lists.
The construction phase ends with the verification of systems start-up. The CA will prepare a report verifying that systems start-up has been successfully completed and the Cx process begins the Acceptance Phase. The CA has previously prepared functional performance tests to verify the operation of the system. Typically, start-up means energizing the equipment and recording temperatures and pressures to ensure the equipment is operating as the manufacturer intended. A successful start-up verifies that safety devices are operating and the components are functioning normally. Start-up does not verify that the hot water reheat valve can stroke full open on a call for heat, or full closed on a call for cooling, or modulate on a call for dehumidification. The CA prepares procedures of how the system will function, how the system will be FPT and verification of compliance. When the system doesn’t comply, the CA will offer suggestions of how the system maybe modified to meet compliance.
To end the Acceptance phase, the CA compiles the as-built drawings, the Systems manual and prepares the CX report. The Cx report indicates that the commissioned systems have been installed and are operating in accordance with the CD. If this is not true for all Cx systems then the CA summarize the deficiencies, offer potential remedies, and recommend acceptance or rejection by the owner.
The objective of the post-acceptance phase is to maintain the performance of the systems throughout the useful life of the facility. As part of the Cx contract, the CA will provide owner support through-out the warranty period; addressing new deficiencies, verifying the off-season testing, and modification of the Systems Manual and as-built drawings to reflect facility changes.
According to BOMA, commissioning can provide energy savings from $0.50 - $1.25/sq. ft. Maintenance savings of $0.50 - $1.25/sq. ft. can be achieved. Employee productivity can increase from 6% – 16%. These are only some of the potential savings. How much will these savings cost? Building commissioning ranges from 1.5% - 3% of the construction cost, HVAC & BAS commissioning ranges from 2.5% – 5% of the mechanical cost, and the lighting and power system ranges from 1% – 2%. The real question should be, how can I afford not to commission by facility?
Every consumer wants to pay the right price. No one knowingly chooses to overpay. Many prefer to underpay, thinking they have found a bargain. Is the lowest price the best price? I believe the right price is best explained by a 19th century Economist named John Ruskin.
“It is unwise to pay too much, but it’s worse to pay too little. When
you pay too much, you lose money, that is all. When you pay too
little, you sometimes lose everything because the thing you bought
was incapable of doing the thing it was bought to do. The common
law of business balance prohibits paying a little and getting a lot, it
can’t be done. If you deal with the lowest bidder, it is well to add
something for the risk you run, and if you do that you will have
enough to pay for something better.”
This article was originally printed in the summer 2002 edition of the Blueline; the newsletter of the NJ Chapter of the Healthcare Facility Managers Society.
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