ASHRAE Journal - February 2014 - 53

OPR and [verifying that] the components, systems, and
assemblies in the design directly relate to the testability,
accessibility, maintainability, efficient operation, and
industry-accepted best practices" [italics in original text].
Design phase commissioning is the process of comparing each element of the design to the OPR... [and helping] the design team [ensure that] the Basis of Design
meets the requirements of the [OPR]."
Both definitions are rather flexibly worded and do not
define the details of the CxA's many DPC functions. For
example, DPC should include an independent review
of the contract documents to identify items that may
be missing or issues that may be improperly or incompletely documented.
DPC is not an engineering "peer review" process.
Instead, the goal of DPC is to review the project's design
documents and identify issues during the schematic
design (SD) process-well before any actual design work
is completed. After all, to be successful, a project doesn't
need false starts or design rework. The ultimate objective is
a building that works properly, can be tested to verify correct operation, and then maintained on an ongoing basis.
DPC provides an important quality check that is missing from too many construction projects.

Who's Responsible?
I sometimes hear a CxA say, "We'll review the design
to ensure that the building has appropriate means and
devices that will enable specific tests to be performed
and conditions to be measured during commissioning. We'll also review the drawings to ensure there are
adequate spaces and clearances for performing routine
maintenance. But the engineer of record is responsible
for the building's design."
It's true that engineers are responsible for building
design. But the commissioning process exists because
traditional design, engineering, construction, and startup processes too often have delivered buildings that
don't meet owner expectations. A properly executed
commissioning process provides a system of checks and
balances that is more likely to yield the result the owner
is seeking.
Bottom line? The CxA's job is to drive the commissioning process.

Careful Document Review: Key to Success
On a problem project, everyone is potentially subject to
callbacks, review meetings, and litigation. So it's in the

CxA's best interest to review the project documents as if
he or she were the project's designer.
The CxA needs to be confident that the building
will operate in accordance with the OPR document.
Therefore, the CxA team should be comprised of professionals who are experts in the design and operation
of their various areas of specialization (architecture,
mechanical, electrical, etc.).
It's important to stress the impact of the OPR and BOD
documents in DPC. A well-written OPR clearly spotlights
a wide range of design specific considerations, and an
effective BOD document explains how the design team
will address those considerations.
The goal of commissioning is to produce a building
that works, so it's unwise to begin DPC when the construction drawings are already 50% complete. A design
change at that point in the project can become a costly
proposition for both the owner and the A/E firm, and
can create an adversarial relationship between them.
The commissioning process will fail if the CxA doesn't
question apparent inconsistencies. For example, an
air-handling system that generates 0.5 in. of static
pressure (124 Pa) cannot deliver the airflows required
for a system that is designed around 1.5 in. of pressure (373 Pa). Such an error in specifying static pressure would prevent the HVAC system from providing
design mandated airflow volume throughout the entire
building.
By beginning DPC during the schematic design process, such mistakes can be found and corrected before
they become costly and burdensome. DPC continues
through the creation of the design development (DD)
documents and is finalized during the preparation of
the construction drawings (CD)-but before the project
bidding process begins.
While effective DPC should include detailed reviews
of the project's architectural, mechanical, and electrical
(A/M/E) components, technical commissioning does not
typically include code, structural, or civil engineering
reviews (although such elements may sometimes be
evaluated for specific projects). Therefore, this series of
articles deals only with the A/M/E-related portions of the
construction process.

Architectural Design Review
The first category of DPC considerations the CxA must
evaluate relates to the building's architectural design
elements. Based on our experience, some of the more
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