Commissioning - Is it the Answer to HVAC Problems?
By: Maureen P. Taylor
Reprinted from July 2003 ohioconstructionlaw.com
The Problem. Which system in a new building
is likely to require 15 to 25% of the construction
budget and cause most of the headaches after construction
is finished? If you answered the HVAC (heating,
ventilation and air conditioning) system, either you have
been reading back issues of ohioconstructionlaw.com
(specifically, the March 2003 issue), or you really know
the construction industry.
The “rule of thumb” for the cost of an HVAC system
met with general agreement at the Roundtables
sponsored last winter by Bricker & Eckler LLP’s
Construction Law Department. The problems encountered
with HVAC systems surfaced repeatedly
in Bricker & Eckler’s annual surveys of school construction
projects over the last four years. Year after
year, more schools reported problems with the
HVAC system than with any other system, including
roofing. In 2002, for instance, 40% of respondents
reported that their HVAC systems either had problems
requiring considerable efforts to correct or
had problems that were still not corrected at the time
of the survey.
With all of the improvements in technology,
why don’t HVAC systems always work as their
owners expect them to work? The technological
sophistication of the systems themselves may be
partly to blame. Today’s systems require more
above-ceiling installation, have to meet more
demanding codes, and have much more complicated
controls than the older systems. There are more
design options than ever before, and therefore more
opportunities for design problems.
At the same time, as Tony Furst, Senior Project
Administrator for Commissioning Services with
Heapy Engineering, Inc., points out, the construction
industry has gotten more and more competitive.
Increased competition encourages contractors to cut
costs by installing their equipment and then walking
away, without providing some of the services that
used to be standard. The result? HVAC and other
systems that operate at less than peak efficiency -
sometimes a lot less.
Is there an answer, a way to assure that these expensive
systems will operate as intended and designed,
saving the owner in the long run on operating costs?
Many in the industry think that the process of Commissioning
provides at least a partial answer. In the
last decade or so, Commissioning for new buildings
has gotten increased attention.
What Is Commissioning? The standard definition
comes from an influential publication from ASHRAE,
the American Society of Heating, Refrigeration and
Air-Conditioning Engineers, Inc.:
[Commissioning is] the process of ensuring
that systems are designed, installed, functionally
tested, and capable of being operated and
maintained to perform in conformity with the
design intent. [The process] . . . begins with
planning and includes design, construction,
startup, acceptance and training, and can be
applied throughout the life of the building.
[ASHRAE Guideline 1-1996, “The HVAC
Commissioning Process,” Clause 4.2]
As the Guideline says, “Owners can use the process
to achieve quality from the start in lieu of inspecting
for quality or modifying the system after the facility
is occupied.”
What “systems” are involved in the Commissioning
process? HVAC, of course, which includes air
handling systems, hot water, chiller, and controls, but
commissioning specifications can also include such
systems as the electrical switchgear and the fire
detection system.
Although the Ohio Basic Building Code does not
require Commissioning (yet), the Ohio School Facilities
Commission recognizes its importance. Furst
says that Heapy Engineering has contracted to develop
Commissioning specifications to be included
either in an addendum to or in a revision of the OSFC
Design Manual. When the new specifications are
issued, he expects Commissioning to be required for
any project still in the design phase. So many school
districts - and many contractors - will need to understand
what Commissioning entails. And if the
schools require it, can other public construction
be far behind?
To visualize how Commissioning works, consider
the same hypothetical project with and without
Commissioning.
How Does It Work Without Commissioning? In
the typical construction project - without
Commissioning - the contractors are responsible for
seeing that their own systems comply with the design
documents and are working. Most follow the
specifications, but occasionally, in Furst’s experience,
a contractor will “throw the spec away” and do
something else. Either the Mechanical Engineer or a Construction Manager with expertise in HVAC
systems may catch some nonconforming work. But
a CM can’t be an expert in everything, so some
problems get missed. To a certain extent, a CM has
to rely on the contractors to do their jobs.
Once the equipment is installed, a TAB contractor
(in charge of Testing, Adjusting, and Balancing) tests
out the equipment and prepares a TAB or “balance”
report listing any deficiencies noticed. TAB contractors
can be prime contractors but are more commonly
subs to the mechanical contractor. If so, they submit
their balance report to the mechanical engineer in
draft form. The final balance report from the mechanical
contractor may or may not be the full report
of the TAB contractor. And TAB contractors can
miss things, too - sometimes whole systems, such as
the chilled water system in one recent project Tony
Furst recalls.
As the building nears Substantial Completion, the
process of field inspection generates punchlists of
deficiencies or exceptions in the various systems.
Does each system comply with acceptable industry
standards and with the shop drawings? If not, a note
of the deficiency is made on the punchlist. But no
one checks to see if the system is working at peak
efficiency; the questions are merely (1) is it the equipment
called for, and (2) is it operating?
If everyone has complied with the contract, installed
the equipment as designed, and done a good job, all
systems may be go at the start. The building is occupied,
and the contractors leave.
Then the seasons change, different equipment kicks
on, and the maintenance staff has some questions.
Why isn’t Room 106 as cool/warm as Room 206?
Why do the fans make so much noise first thing in
the morning? Why are the electric bills so much
higher than they were in the old building? Dissatisfaction
builds, and eventually someone calls a
meeting of the contractors involved. After much
finger-pointing, everyone agrees that something
should be done. But who should do it, and who
should pay for it? If the situation is bad enough, this
can lead to an all-out dispute that may only end
before an arbitrator or in a court of law.
How Does It Work With Commissioning? With
Commissioning, the same project would involve an
additional professional, the “Commissioning Authority”
or “Commissioning Agent.” (Take your pick;
you can abbreviate either one “CA.”) The CA can
be an employee of the owner, the Construction Manager,
or an independent professional. The role of the
CA, according to the ASHRAE Guideline, is to represent
the owner’s needs and implement the overall
Commissioning process, from the program phase of
the project through at least the first year of operation.
So the CA starts as soon as the project is underway.
The CA reviews the plans and specs to be sure all
items related to the HVAC system are complete
and adequate to do the job as the owner intends.
Initially, the CA works with the design professionals
to prepare a Commissioning Plan that will evolve
through each phase of the project. In the program
phase, part of the Commissioning Plan includes
identifying the members of the Commissioning Team,
which will be led by the CA and may include nine
or more other individuals:
The Mechanical Engineer;
The General Contractor’s Representative(s);
The Controls Contractor’s Representative(s);
The Sheet Metal Contractor’s
Representative(s);
The Electrical Contractor’s Representative(s);
The Fire Detection Contractor’s
Representative(s);
The Mechanical Contractor’s
Representative(s);
The Air Balance (or TAB) Contractor’s
Representative(s); and
The Owner’s Representative(s).
Shortly after the contracts are awarded, the CA calls
together all the Team members for a Commissioning
Kickoff Meeting. From this meeting should emerge
tentative schedules for inspections, systems testing,
balancing, performance testing, and training the
owner’s personnel. Thus begins the process
of coordinating the contractors, subs,
suppliers, and owner’s representatives.
Once the equipment is installed, the CA will
coordinate the inspections, check the work
of the TAB contractor, receive and review
maintenance manuals, witness the startup
of each system, and document, document,
document. According to Furst, documentation
is a strong point of the Commissioning
process. For a typical school, for
instance, the assembled Commissioning
documents will fill a three-inch binder.
An important item in the documentation
is the Functional Testing Log, a specific
checklist for each system (the chilled water
system and the air handling unit, for
instance) that specifies in minute detail the
tests to be performed and the responses
desired from the equipment. If the responses
are below par, the appropriate
contractor must adjust or replace the less-than-satisfactory
equipment. (This requirement must be
written into each contract, so that each contractor recognizes the obligation to correct any deficiency
noted on the Log.)
When the checklist is completed, everyone involved
signs off on the Log. The appropriate contractors
and the Construction Manager certify that the system
and equipment involved meet the functional requirements
described in the Log. The CA and
owner’s representative sign to show they have witnessed
the testing and approve the results. Both the
owner and the contractors have assurance that the
system is working at peak efficiency.
All of this documentation is invaluable when it comes
to training the owner’s operation and maintenance
staff. Heapy Engineering makes a point of inviting
the maintenance staff to all of the functional
testing sessions. When it is time for the
final training session, each contractor submits
an outline of what it plans to cover,
and the contractors and CA work together
to educate those who will be running the
equipment on ways to get the most efficient
performance from it.
Then the building opens, and the contractors
move on to other projects. But the
Commissioning Agent or Authority continues
under contract for the next year (or
longer, if the project is particularly huge or
complex). When the seasons change and
new equipment shifts into gear, the CA is
there to witness the startup and to monitor
the systems’ performance. Everything
should continue to operate smoothly. But
if it doesn’t, the CA has the original documentation
to consult. A quick check of the
Functional Testing Log should reveal what
has changed since the beginning, when the
system was working properly.
Where Do You Find a Commissioning
Agent? Opinions differ on whether the Commissioning
Agent or Authority should be independent from
the other players in the construction process. The
ASHRAE Guideline calls it “logical” to choose an employee
of the owner to fill the role. Others argue for
independence.
Many owners, of course, would have trouble finding
a person on-staff to meet the suggested qualifications.
These, according to ASHRAE, should include at least
these six “minimums”:
At least five years of construction experience;
Experience or training with the ASHRAE commissioning
process;
Controls and instrumentation experience;
Knowledge of specific types of buildings and
HVAC systems, and experience with them;
Excellent oral and written communication skills;
and
Experience working with multidisciplinary teams.
Other qualifications ASHRAE recommends include
design experience, operation and maintenance experience,
knowledge of testing, adjusting, and balancing,
knowledge of life safety codes, and professional
registration.
If no employee of the owner quite fills the bill, a check
of engineering firms and construction management
firms may be in order. Since Commissioning is still
relatively new, many consulting engineers are just
getting into the Commissioning business. According
to Tony Furst, there is no nationally accepted certifying
authority for Commissioning Agents, although
the National Environmental Balancing Board is working
to develop one.
What’s It All Going To Cost? Part of drawing up
the initial Commissioning Plan includes developing
a budget for the process, an estimate of what it is all
going to cost. Much depends, of course, on the size
and complexity of the facility. Furst thinks a good
rule of thumb is that the Commissioning fee should
run about one to two percent of the Architect’s fee.
Will the contractors increase their bids, knowing that
the project involves commissioning? The answer to
that varies, depending on the contractor. In Furst’s
experience, the more responsible contractors will see
commissioning as a coordinated effort to assure that
what ought to be done anyway is being done by everyone.
Since no additional work is called for, they
see no reason to increase their bids. Others may add
as much as three or four percent to their bids.
Is This Expense Really Necessary? For some owners,
Commissioning is a hard sell. They agree with
one Roundtable participant who put it this way:
“Look, I’m already paying an Architect, a Mechanical
Engineer, a Mechanical Contractor, a Construction
Manager, a Controls Subcontractor, and an Air-
Water Balance Subcontractor. Do I really have to
pay for a Commissioning Agent, too? Why can’t they
all just do their jobs right, so my HVAC system will
work properly?”
There are really three answers to this question, with
some truth to each.
The first and simplest answer is that the skeptical
owner is right. If all the jobs were done properly,
then the system should work properly. In the best
of all possible worlds, Commissioning would be
unnecessary.
But we don’t live in the best of all possible worlds, at
least not yet. The second and more realistic answer
lies in the description of the problem itself: The
sophisticated technology of today’s systems makes coordination of the various contractors and their
equipment vital. It is not enough that each piece work
properly in isolation. Each piece must be adjusted,
calibrated, and integrated with the other equipment
in the building. The whole is really equal to more
than the sum of the parts, and only the Commissioning
Agent knows and understands the whole.
The third answer is that it is possible to draft the frontend
documents to achieve many of the benefits of
Commissioning without calling for a separate Commissioning
Agent. One way to do this is to involve
the Mechanical Engineer at an earlier stage than usual.
For instance, in many of the Owner-Architect Agreements
drafted by Bricker & Eckler attorneys, the
Schematic Design Phase calls for an early meeting
in which the Architect, Mechanical Engineer, Construction
Manager and owner review the owner’s
expectations of the HVAC system and discuss the
options available, the costs of operation and maintenance,
and the costs and benefits of the Commissioning
process, a life cycle cost analysis, and a maintenance
agreement for the HVAC system. Such a meeting
should lead to shorter follow-up meetings in later
phases of the construction process.
System testing during the first year of operation can
also be included in the front-end documents, of
course. It is an open question whether these contractual
additions will actually achieve the results of Commissioning
without the costs. If much of the Commissioning
Agent’s work is built into the Architect’s or
Mechanical Engineer’s role, won’t their fees be increased
accordingly? That’s certainly a possibility.
Do the Benefits Justify the Costs? The costs of
Commissioning should be balanced against what
Furst and others in the industry see as the considerable
benefits of the Commissioning process:
Receiving a building with few or no system deficiencies;
Optimal performance that results in much lower
energy costs (Furst tells of one school where the
annual cost of energy works out to $2.50 per
square foot);
Assured compliance with warranty requirements;
Minimal complaints from occupants; and
The joy of avoiding the headaches that come with
moving into a non-functioning building or one
that just doesn’t work the way it should.
How Do You Get Started? If you want to learn
more about the Commissioning process - or if you’ve
already decided you want to include it in
your next project - a good place to begin
is with the ASHRAE Guideline 1-1996,
“The HVAC Commissioning Process.”
The Guideline can be ordered on
the Internet, either in a print or a
downloadable version.
Other resources available from the
ASHRAE online bookstore will help you
calculate the costs of Commissioning, establish
Commissioning fees, and develop
specifications and RFPs for Commissioning
services. These should prove invaluable
as you begin at the beginning, revising your contracts
and other front-end documents so that they
include Commissioning.
Thanks to Tony Furst of Heapy Engineering, Inc.,
for reviewing and contributing to this article.
