Acoustical Design Criteria
The program shall be capable of calculating each zone's
peak heating and cooling load as well as the whole-
All mechanical systems must be designed to satisfy the
building "block" loads. The program shall, at a minimum,
acoustical design criteria detailed in Chapter 3.
calculate: solar gains through fenestration, internal gains
from occupants including latent heat for cooling
Thermostatic Zoning Design Criteria
purposes, internal gains from lighting and equipment,
outside air loads (sensible and latent) from ventilation
Interior thermostatic control zones must not exceed
and infiltration, and heat gains or losses through
139 m2 (1,500 sq.ft.) per zone for open office areas or
fenestration, walls, floors and roofs. The heating load
a maximum of three offices per zone for closed office
calculations must be done without credit for occupants
and internal gains.
Perimeter thermostatic control zones shall not exceed
The HVAC loads calculations report shall include all
28 m2 (300 sq.ft.) and shall be no more than 4.6 m (15 ft)
input and output used in the heating and cooling
from an outdoor wall along a common exposure. Corner
calculation program, and shall include zone peak heating
offices shall be a dedicated zone.
and cooling loads results, and whole building "block"
If a building program shows that an office building shall
loads, air-handling unit coil selections, and psychrometric
have an open plan layout or if the program does not state
a preference, it may be assumed that up to 40 percent of
the floor plan shall be occupied by closed offices at some
Energy Calculations. A building energy analysis shall be
point in the future.
performed to demonstrate that the building design meets
or exceeds the energy performance goals established for
Single air-handling units shall not serve multiple floors
the project. Refer to Chapter 1 for specific energy
or scattered building loads. Systems designed for Federal
performance goals requirements.
Courthouses shall have no more than two courtrooms
served by a single air-handling unit, and that air-handling
The building energy analysis shall be performed using the
unit shall be dedicated to serving only those two
ASHRAE Standard 90.1 Energy Cost Budget methodology,
and must demonstrate compliance with the latest
editions of ASHRAE Standard 90.1, 10 CFR 434, and
10 CFR 435. The analysis shall be included in each design
HVAC Loads Calculations
submission as described in Appendix A.3.
and Energy Calculations Criteria
The analysis shall evaluate the energy performance of
HVAC Loads Calculations. The HVAC loads calculations
the building design including the proposed building
shall be preformed with a computer-based program using
envelope, HVAC systems and components, the lighting
the latest ASHRAE Handbook of Fundamentals Heat
systems, and domestic hot water systems, as well as the
Balance Method (HB), Radiant time Series (RTS)
proposed control strategies for these building systems.
Method, or Transfer Function Method (TFM), developed
for the hourly analysis of heating and cooling loads in
124 F A C I L I T I E S S T A N D A R D S
5.3 Design Criteria
Revised March 2005 PBS-P100