pdfcoffee.com_hvacsimplifiedpdf-pdf-free

Introduction to HVAC
2. who has hired competent engineers that provide
thorough, code-compliant drawings and specifications
in a timely manner,
3. so that experienced and qualified contractors can
provide sound bids.
If the low bid is too high, the building is “valueengineered,”
or downsized, to meet the available budget.
Great care and open communication are necessary to
make adjustments that do not alter the building’s
intended functions and operating characteristics.
Although the time schedule is often abbreviated, design
drawings and specifications must be modified with
thoughtful consideration being given to the impacts of
lower-cost substitutions. The project is then re-bid and
initiated. However, costs may skyrocket due to many
noncompetitive bid “change orders” that are required
because of the lack of time available to thoroughly redesign
the building to meet the lower budget.
Figure 1.2 is the design-build alternative to the
plan-bid method of designing and constructing buildings.
In this situation, the owner hires a design-build
contractor who employs either in-house architects and
engineers or hires external firms. The project manager is
the design-build general contractor and all the subcontractors
work for the design-build firm. Subcontractors
can also be outside firms.
This arrangement fosters better cooperation among
participants, and the cost of change orders is the responsibility
of the design-build firm. However, the level of
checks and balances among architects, engineers, and
contractors is reduced, which may leave the owner-customer
more at risk. Savvy owners will likely hire a
building professional to oversee the work of the designbuild
firm.
THE ROLE OF AN HVAC ENGINEER
Successful engineering firms consistently obtain
projects, which ensures steady income during normal
business cycles. These firms develop a positive reputation
by establishing trust with architects, construction
managers, and owners. Their reputation is enhanced by
a record of promptness, dependability, and completing
projects on time and within budget. HVAC engineers in
such a firm do the following:
1. Establish relationships with other design team
members to maximize cooperation and coordination
of system integration and construction.
Figure 1.2
Design-build organization chart.
3