[Code of Federal Regulations]
[Title 10, Volume 3]
[Revised as of January 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 10CFR435.105]
[Page 426-549]
TITLE 10--ENERGY
CHAPTER II--DEPARTMENT OF ENERGY
PART 435--ENERGY CONSERVATION VOLUNTARY PERFORMANCE STANDARDS FOR NEW BUILDINGS; MANDATORY FOR FEDERAL BUILDINGS--Table of Contents
Subpart A--Voluntary Performance Standards for New Commercial and Multi-
Family High Rise Residential Buildings; Mandatory for Federal Buildings
Sec. 435.105 Building Envelope.
5.1 General
5.1.1 This section contains requirements for the energy conscious
design of building envelopes. It sets principles of good envelope
design, and provides a set of minimum requirements and two alternative
compliance paths--prescriptive and system performance.
5.1.2 Compliance. A building shall be considered in Compliance with
this section if the following conditions are met:
5.1.2.1 The minimum requirements of Section 5.3 are met;
5.1.2.2 The design of the building envelope complies with either
the prescriptive criteria of section 5.4 or the system performance
criteria of section 5.5. For the design of buildings with high internal
heat gains, unusual operating schedules, or that incorporate innovative
design strategies, consideration shall be given to using the compliance
paths set forth in sections 11.0 or 12.0.
5.1.3 The prescriptive compliance alternative of section 5.4
provides requirements for buildings designed to take advantage of
perimeter daylighting, thermal mass, high performance glazings, and
fenestration shading. The designer is allowed to make trade-offs between
thermal mass, wall insulation, amount of fenestration, shading
coefficients, shading projections, thermal transmittance of the glazing,
daylighting for several different climate locations.
5.1.4 The systems performance compliance alternative of section 3.5
provides calculation procedures that give credit for the benefits of
more complex energy conserving envelope designs.
[[Page 427]]
5.1.5 Information on thermal properties, performance of building
envelope sections and components, and heat transfer shall be obtained
from the ASHRAE Handbook, 1985 Fundamentals Volume. When information is
not available from this source, the data shall be obtained from
laboratory or field test measurements conducted in accordance with ASTM
Standard C-177-85, ``Standard Test Method for Steady-State Thermal
Transmission Properties by Means of the Guarded Hot Plate,'' ASTM
Standard C-518-85, ``Steady-State Thermal Transmission Properties by
Means of the Heat Flow Meter,'' ASTM Standard C-236-80, ``Standard Test
Method for Steady-State Thermal Performance of Building Assemblies by
Means of a Guarded Hot Box,'' and ASTM Standard C-976-82, ``Thermal
Performance of Building Assemblies By Means of a Calibrated Hot Box.''
5.1.6 Daylighting Credit. In this section, daylighting credit for
reduced energy use resulting from the use of automatic lighting control
devices in conjunction with fenestration, is given only for space
heating and cooling loads. Credit for the reduced use of electric
lighting energy is calculated in section 3.5.6. If daylighting credit
for reduced electric lighting energy use is desired to be applied to
other building systems, such as more fenestration area, section 11.0 or
12.0 should be used.
5.1.7 The requirements of this section are not intended to replace
building loads calculation procedures.
5.2 Principles of Design
5.2.1 Building Loads
5.2.1.1 Building loads result from sources external and internal to
the building. (1) External loads, from outdoor temperature, humidity,
wind, and insolation, fluctuate daily and seasonally. (2) Internal loads
from the activities conducted within the building, including heating and
moisture produced by the occupants, lights, and process equipment (e.g.,
appliances, computers) vary with internal activities. Improving energy
efficiency in a building depends on achieving a balance between and
among the internal and external loads. The building design should,
therefore, offset gains and losses of heat, light, and moisture between
the interior and exterior of the building, among interior spaces, and
over-time, (daily, seasonally, and annually).
5.2.1.2 This balance of loads can be most efficiently achieved if
the building envelope is viewed as, and designed to be, a controlled
membrane rather than an immutable barrier. The typical design of a
modern building has considered the building envelope to be a fixed
barrier that restricts heat and air flow to the maximum extent possible.
This will not usually yield the most energy efficient building.
5.2.1.3 The desired goal of the energy design of the building
envelope shall be to produce a controlled membrane that allows or
prevents heat, light, and moisture flow to achieve a balance between
internal and external loads. Thus the envelope becomes an integral part
of the building's environmental conditioning systems.
5.2.1.4 To achieve control of the building envelope as a membrane,
and to simultaneously achieve occupant comfort in the perimeter zones,
many of the traditional building skin components must be used
(insulation, mass, caulking and weather stripping). However, other
concepts shall also be considered to temper supply air or utilize waste
heat in exhaust air to temper envelope conditions, such as operable
solar shading devices, and the integration of glazing systems with the
HVAC distribution system.
5.2.1.5 Control of External Loads
5.2.1.5.1 Control of Conduction
(a) Controlled conductivity may be considered through the careful
use of insulation, sensible (mass) or phase-change storage and movable
insulation at levels which minimizes net heating and cooling loads on a
time integrated (annual) basis.
(b) Unintentional or uncontrolled thermal bridges shall be minimized
and considered in energy related calculations since they can radically
alter the conductivity of a building envelope. Examples include wall
studs, balconies, ledges, and extensions of building slabs.
[[Page 428]]
5.2.1.5.2 Control of Infiltration (Heat Loss or Gain)
(a) Infiltration shall be minimized and all efforts to achieve a
zero level shall be taken. This will minimize fan energy consumption in
pressurized buildings during occupied periods and heat loss (or unwanted
heat gain in warm climates) during unoccupied periods. Infiltration
reduction shall be accomplished through design details that enhance the
fit and integrity of building envelope joints in a way that may be
readily achieved during building construction. This includes
infiltration control by caulking, weather stripping, vestibule doors
and/or revolving doors with construction meeting or exceeding accepted
specifications.
(b) The quantity of mechanical ventilation must vary with the need,
with recommended values at any given time equal to that required by
ASHRAE Standard 62-1981. Higher levels of ventilation (e.g.,
economizers) shall be considered to substitute for mechanical cooling.
(c) Operable windows may be considered to allow for occupant
controlled ventilation. When using operable windows, the design of the
building's mechanical system must be carefully executed to minimize
unnecessary HVAC energy consumption, and building operators must be
cautioned about the improper use of the operable windows.
(d) Non-mechanical ventilation can be enhanced in the shape of the
building as well as the physical elements of the building envelope, such
as cupolas.
(e) For hotels and high rise dwelling units and other systems having
exhaust totalling 3000 cfm or more, with annual operation in excess of
3000 hours and within 200 linear ft of simultaneous make-up air
equipment, they shall incorporate energy recovery or treatment to ASHRAE
62-1981 quality levels and reuse exhaust air when allowed by code.
5.2.1.5.3 Control of Radiated Heat Losses and Gains
(a) Capability for occupant radiant comfort shall be maintained
regardless of whether the building envelope is designed to be a static
or dynamic membrane. Opaque surfaces shall be designed so that the
average inside surface temperatures will remain within 5 deg.F of room
temperature in the coldest anticipated weather (i.e., winter design
conditions), and the coldest inside surface will remain within 25 deg.F
of the room temperature.
(b) In a building with time-varying internal heat generation,
thermal mass may be considered for controlling radiant comfort. In the
perimeter zone, thermal mass is more effective when it is positioned
internal to the envelope insulation.
(c) The effective control of solar radiation is critical to the
design of energy-efficient buildings due to the high level of internal
heat production already present in most commercial building types. In
some climates, the lighting energy consumption savings due to
daylighting techniques can be greater than the heating and cooling
energy penalties from additional glazed surface area, provided that the
building envelope is properly designed for daylighting and lighting
controls are installed and used. In other climates they may not.
Daylighting designs are most effective if direct solar beam radiation is
not allowed to cause glare in building spaces.
(d) The transparent portions of the building envelope shall be
designed to prevent solar radiant gain above that necessary for
effective daylighting and solar heating. On south-facing facades, the
use of low shading coefficients is generally not as effective as
external physical shading devices in achieving this balance. Light
shelves offer a very effective means of admitting daylight while shading
the view glazing and simultaneously allowing occupants to manipulate
interior shading devices (draperies, blinds) without eliminating day
light.
(e) The solar spectrum contains a range of wavelengths including
visible and infrared (heat). Designers shall consider which portion of
the spectrum to admit into the building. For example, low emissivity,
high-visible-transmittance glazings may be considered for the effective
control of radiant heat gains and losses. For shading control designers
may consider the careful use of vegetation that can block excess
[[Page 429]]
gain, year-around or seasonally depending on the plant species chosen.
5.3 Minimum Requirements
5.3.1 Overall Thermal Transmittance (Uo)
5.3.1.1 The overall thermal transmittance of the building envelope
above grade assembly shall be calculated as follows:
[GRAPHIC] [TIFF OMITTED] TC14NO91.061
Equation 5.3-1
Where:
Uo=the area weighted average thermal transmittance of the
gross area of the building envelope assembly, e.g., the
exterior wall assembly including fenestration and doors; roofs
and ceiling assembly; or the floor assembly, Btu/hft \2\
deg.F.
Ao=the gross area of the envelope assembly, ft \2\.
Ui=the thermal transmittance of each individual path of the
envelope assembly (see Section 5.3.2), Ui=1/
Ri (where R1 is the total resistance to
heat flow of an individual path through an envelope assembly).
Ai=the area of each individual element of the envelope
assembly, ft \2\.
5. 3. 2 Thermal Resistance of Below Grade Components (R)
5.3.2.1 In calculating the thermal resistance of all below grade
components, the thermal performance of the adjacent ground shall be
excluded.
5.3.2.2 Slabs
5.3.2.2.1 The R-value required for slabs refers only to the
insulation materials. Insulative continuity shall be maintained in the
design of slab edge insulation systems. Continuity shall be maintained
from the wall insulation through the slab/wall/footing intersection to
the body of the slab edge insulation.
5.3.2.2.2 Slab-on-grade floors shall have insulation around the
perimeter of the floor with the thermal resistance (Ru) of
the insulation specified in accordance with Figure 5.5-2. The slab
insulation specified shall extend either in a vertical plane downward
from the top of the slab for the minimum distance shown or downward to
the bottom of the slab then in a horizontal plane beneath the slab or
outward from the building for the minimum distance shown. The horizontal
length, or vertical depth, of insulation required varies from 24 in. to
48 in. depending upon the R-value selected. For heated slabs, an R of 2
shall be added to the thermal resistance required.
5.3.2.2.3 Vertical insulation shall not be required to extend below
the foundation footing. There are no insulation requirements for slabs
in locations having less than 3,000 HDD65 or for footings extending less
than 18 in. below grade.
5.3.2.2.4 The dimensional requirements for horizontal insulation
refers to the insulation materials only. Horizontal applications shall
have a thermal break in the slab edge that provides continuity between
the wall insulation on the slab and the horizontal insulation.
Below Grade Walls
5.3.2.3.1 The R-value required for Below Grade Walls refers to the
overall R-value of the wall assembly excluding air film coefficients and
the thermal performance of the adjacent ground.
5.3.3 Thermal Transmittance (Ui) of an Envelope Assembly
5.3.3.1 The thermal transmittance of each envelope assembly shall
be determined with due consideration of all major series and parallel
heat flow paths through the elements of the assembly. Compression of
insulation shall be considered in determining the thermal resistance.
5.3.3.2 The thermal transmittance of opaque assemblies
Ui shall be determined using a series path procedure that
corrects parallel paths, such as insulation and studs in a wall cavity
or the roof assembly shown in Figure 5.3-1. Table 5.3-1 prescribes the
procedure to be used for Subsections 5.3.3.2.1 and 5.3.3.2.2.
[[Page 430]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.092
[[Page 431]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.093
5.3.3.2.1 For envelope assemblies containing metal framing, the
Ui shall be determined by using one of the following methods:
(a) Results from laboratory or field test measurements, using one of
the procedures specified in section 5.1.5.
(b) For non-metal surfaces attached to metal framing, where data
from tests conducted using procedures specified in section 5.1.5, such
as those provided in Tables 5.3-2 and 5.3-3, is available, the total
resistance of the series path may be calculated using Equations 5.3-2a
and 5.3-2b, and illustrated in Figure 5.3-1:
[GRAPHIC] [TIFF OMITTED] TC04OC91.094
[[Page 432]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.095
[GRAPHIC] [TIFF OMITTED] TC14NO91.062
Equation 5.3-2a
[GRAPHIC] [TIFF OMITTED] TC14NO91.063
Equation 5.3-2b
Where:
Rt=the total resistance of the envelope assembly
Ri=the resistance of the series elements (for i=1 to n),
excluding the parallel path element(s)
Re=the equivalent resistance of the element containing the
parallel path, the value of Re is:
Re=(R-value of insulation) x Fc
Equation 5.3-2c
Where:
Fc=the correction factor from Table 5.3-2 or Table 5.3-3.
(c) For elements other than those covered in item (b) above, the
zone method described in Chapter 23 of the ASHRAE Handbook, 1985
Fundamentals Volume shall be used. The equations on pages 23.13 and
23.14 shall be used.
(d) For sheet metal construction, internally insulated with an
internal metal structure bonded on one or both sides to a metal skin or
covering (see Figure 5.3-2), the following steps shall be used to
calculate the U-value of the envelope construction.
[[Page 433]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.096
(1) First, calculate the resistance of the thermal bridge
RTB as follows:
[GRAPHIC] [TIFF OMITTED] TC14NO91.064
[[Page 434]]
(i) Where R1, the effective mean flow path along the
outer metal surface, is calculated by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.065
(ii) And if it occurs, the resistance of insulation (R2)
between the outer metal surface and the metal structural member is
calculated by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.066
(iii) And, the resistance of the structural member (R3)
is calculated by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.067
Equation 5.3-6
(iv) And if it occurs, the resistance of insulation (R4)
between the inner metal surface and the purlin flange is calculated by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.068
(v) And finally, the effective mean flow path along the inner metal
surface (R5) is calculated by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.069
Where:
L=total length
h=coefficient of heat transfer
k=thermal conductivity
T=temperature
B=total width
H=partial height
t=thickness of sheet metal
(2) Then calculate the parallel path resistance of the homogeneous
insulation RH as follows:
[GRAPHIC] [TIFF OMITTED] TC14NO91.070
(3) Then obtain the overall construction resistance RC by
combining RH and RTB as two parallel resistances:
[GRAPHIC] [TIFF OMITTED] TC14NO91.071
Equation 5.3-10
(4) Then add the inside and outside surface resistances
Ri and Ru to get the total resistance
RTOT:
[GRAPHIC] [TIFF OMITTED] TC14NO91.072
Equation 5.3-11
(5) The total area resistance mTOT is then calculated by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.073
Equation 5.3-12
(6) And finally, obtain the U-value by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.074
Equation 5.3-13
(7) Where additional resistances are introduced in the construction,
introduce them in lieu of the above (R2 and R4)
resistances. An example of this would be the calculation of both a
metallic fastener and a block of higher thermal conductivity material
between the outer sheet metal and the internal structural member as
shown in Figure 5.3-3. In this case the original R2 is re-
calculated by first calculating the thermal bridge R2TB as
follows:
[[Page 435]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.102
[GRAPHIC] [TIFF OMITTED] TC14NO91.075
Equation 5.3-14
(i) Where the resistance of the heads of number (N) of fasteners per
length
[[Page 436]]
(L), adjusting for surface resistance in common with the sheet metal
surface, is calculated by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.076
Equation 5.3-15
Where:
N=the number of fasteners in Length L
f=the function of B÷ r for different values of the
ratio r2/r1 given in Figure 5.3-4.
[GRAPHIC] [TIFF OMITTED] TC14NO91.077
r1=the radius of the fastener shank.
r2=the outer radius of the fastener head.
[[Page 437]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.103
(ii) And, the resistance of the shank of the fastener is calculated
by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.078
Equation 5.3-16
(iii) And, finally, the resistance of the connection to the internal
structural member is calculated by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.079
(iv) Then calculate the resistance of the block of higher thermal
conductivity material as follows:
[[Page 438]]
[GRAPHIC] [TIFF OMITTED] TC14NO91.080
Where:
12
(v) Then obtain the resistance to be used in lieu of the original
R2 by:
[GRAPHIC] [TIFF OMITTED] TC14NO91.081
Equation 5.3-19
5.3.3.2.2 For envelope assemblies containing Non-Metal Framing, the
Ui shall be determined from one of the laboratory or field
test measurements specified in Section 5.1.5 or from the ASHRAE series-
parallel method. Formulas in Chapter 23, page 23.2 of the ASHRAE
Handbook, 1985 Fundamentals Volume, shall be used for these
calculations.
5.3.3.3 The thermal transmittance of fenestration assemblies shall
be corrected to account for the presence of sash, frames, edge effects
and spacers in multiple-glazed units.
If thermal transmittances of sash and frames are known, Equation
5.3-1 shall be used, otherwise the thermal transmittance offenestration
assemblies shall be calculated as follows:
Uof=
Ugi x Ff,i x Ai/
Aof=
(Ug,1 x Fe,1 x A1+Ug,2 x Ff,2
x A2+ . . .
+Ug,n x Ff,n x An)/Aof
Equation 5.3-20
Where:
Ai=area of ith fenestration assembly
i=numerical subscript (1,2, . . . n) refers to each of the various
fenestration assemblies present in the wall
n=the number of fenestration assemblies in the wall assembly.
Uof=the overall thermal transmittance of the fenestration
assembly, including sash and frames, Btu/hft\2\ deg.F.
Ug=the thermal transmittance of the central area of the
fenestration excluding edge effects, spacers in multiple-
glazed units, and the sash and frame, Btu/hft\2\ deg.F.
Ff,i=framing adjustment factor for sash, frames, etc.
Aof=the area of all fenestration including glazed portions,
sash, frames, etc.
5.3.3.3.1 Values for Ug shall be the winter value
obtained from the glazing manufacturer's test data or from Table 13 or
Figure 14 of Chapter 27 of the ASHRAE Handbook, 1985 Fundamentals
Volume. Values for Ff shall be obtained from the frame
manufacturer's test data or from the average adjustment factor for a
particular product in Table 13, Part C, in Chapter 27 of the ASHRAE
Handbook, 1985 Fundamentals Volume. For glass products with a U value of
0.45 or less, use the Ff for triple insulated glazing.
Alternatively, values of the Ug deg.F product may be used
from manufacturer's test data for open window and frame assemblies
tested as a unit provided that the tests referenced edge-effects and
windspeed are accounted for winter tested U-values are used.
5.3.4 Gross Area of Envelope Components
5.3.4.1 The gross area of a roof assembly consists of the total
surface of the roof assembly exposed to outside air or unconditioned
spaces. The roof assembly shall include all roof/ceiling components
through which heat may flow between indoor and outdoor environments
including skylight surfaces, but excluding service openings.
5.3.4.1.1 For thermal transmittance purposes, when return air
ceiling plenums are employed, the roof/ceiling assembly shall not
include the thermal resistance of the ceiling, or the plenum space, as
part of the total thermal resistance of the assembly.
5.3.4.2 The gross area of a floor assembly over outside or
unconditioned space consists of the total surface of the floor assembly
exposed to the outside air or an unconditioned space. The floor assembly
shall include all floor components through which heat may flow between
indoor and outdoor or unconditioned space environments.
5.3.4.3 The gross area of exterior walls enclosing a heated or
cooled space is measured on the exterior and consists of the opaque wall
including between floor spandrels, peripheral edges of flooring, window
areas including sash and door areas, but excluding vents, grilles and
pipes.
5.3.5 Shading Coefficients
5.3.5.1 The Shading Coefficient (SC) for fenestration shall be
obtained from Chapter 27 of the ASHRAE Handbook,
[[Page 439]]
1985 Fundamentals Volume or from manufacturers' test data. For the
prescriptive or system performance envelope compliance calculations in
sections 5.4 and 5.5, a factor, SCx, is used. SCx
is the Shading Coefficient of the fenestration, including internal and
external shading devices, but excluding the effect of external shading
projections, which is calculated separately. The shading coefficient
used for louvered shade screens shall be determined using a profile
angle of 30 deg., as found in Table 41, Chapter 27 of the ASHRAE
Handbook, 1985 Fundamentals Volume.
5.3.6 Wall Heat Capacity
5.3.6.1 Heat capacity in Btu/ deg.Fft\2\, shall be determined as
the product of the average wall weight in lb/ft\2\ and the weighted
average specific heat of the wall component in Btu/lb deg.F.
5.3.6.2 If the wall system is defined as having exterior insulation
only the properties of the wall elements inside of the insulation layer
shall be used in determining the wall heat capacity.
5.3.6.3 For walls with integral insulation, all of the elements of
the entire wall system may be used in the calculation of the wall heat
capacity.
5.3.7 Air Leakage and Moisture Migration
5.3.7.1 The requirements of this subsection apply only to those
locations separating the outdoors from interior building conditioned
space. Compliance with the criteria for air leakage through building
components shall be determined by ASTM E 283-1984, ``Standard Method of
Test Rate of Air Leakage Through Exterior Windows, Curtain Walls and
Doors.''
5.3.7.2 Air Leakage Requirements for Fenestration and Doors
5.3.7.2.1 Fenestration meeting the following standards for air
leakage is acceptable:
(a) ANSI/AAMA 101-85, ``Aluminum Prime Windows.''
(b) ASTM D-4099-83, ``Specifications for Poly(VinylChloride) (PVC)
Prime Windows.''
(c) ANSI/NWMA I.S. 2-80, ``Wood Window Units (Improved Performance
Rating Only).''
5.3.7.2.2 Sliding Doors shall meet one of the following standards
for air leakage:
(a) ANSI/AAMA 101-85, ``Aluminum Sliding Glass Doors.''
(b) NWMA I.S. 3-83, ``Wood Sliding Patio Doors.''
5.3.7.2.3 Commercial entrance swinging or revolving doors shall
limit air leakage to a rate not to exceed 1.25 cfm/ft2 of
door area, at standard test conditions.
5.3.7.2.4 Residential swinging doors shall limit air leakage to a
rate not to exceed 0.5 cfm/ft2 of door area, at standard test
conditions.
5.3.7.2.5 Where spaces have regular high volume traffic through the
building envelope, such as retail store entrances and loading bays,
estimates of air leakage for HVAC system design shall be based on air
exchange by traffic flow.
5.3.7.2.6 To reduce infiltration due to stack-effect draft in
multi-story buildings, the use of vestibules or revolving doors on all
primary entries and exits shall be considered.
5.3.7.3 Air Leakage Requirements for Exterior Envelope Joints and
Penetrations.
5.3.7.3.1 Exterior joints, cracks, and holes in the building
envelope, such as those around window or door frames, between wall and
foundation, between wall and roof, through wall panels at penetrations
of utility services or other service entry through walls, floors, and
roofs, between wall panels, particularly at corners and changes in
orientation, between wall and floor, where floor penetrates wall, around
penetrations of chimney, flue vents, or attic hatches, shall be caulked,
gasketed, weather stripped, or otherwise sealed.
5.3.7.4 Moisture Migration Requirements for Exterior Envelopes
5.3.7.4.1 The building envelope shall be designed to prevent
moisture migration that leads to deterioration in insulation performance
of the building.
5.3.7.4.2 Vapor retarders shall be considered to prevent moisture
from collecting within the envelope. Designs should incorporate the
principles of ASHRAE Handbook, 1985 Fundamentals Volume, Chapter 21,
``Moisture in Building Construction.''
5.3.8 Shell Buildings
5.3.8.1 The following conditions shall be assumed if determination
of
[[Page 440]]
building envelope compliance occurs prior to the determination of
lighting power density, equipment power density, or fenestration shading
device characteristics:
5.3.8.1.1 Lighting Power Density and Equipment Power Density. For
section 5.4, the total power density shall be assumed to be those listed
in Table 5.3-4. For section 5.5, the values in Table 5.3-4 shall be
assumed to be apportioned as \2/3\ lighting and \1/3\ for other
equipment. Note that these are not recommended design values, but are
for compliance purposes only.
[GRAPHIC] [TIFF OMITTED] TC04OC91.106
5.3.8.1.2 Fenestration shading devices. Only those shading devices
that are part of the design when it is being evaluated for compliance
shall be considered when determining compliance.
5.3.8.1.3 Daylighting controls for electric lighting. Only those
controls that are part of the design when it is being evaluated for
compliance shall be considered when determining compliance.
5.3.9 Buildings Located in Climates With Greater Than 15,000 HDD
Base 65 deg.F.
5.3.9.1 For locations with a heating degree-day base (HDD) 65
o F greater than 15,000, the envelope criteria listed in
Table 5.3-5 shall apply, and the window wall ratio (WWR) shall be less
than or equal to 0.20.
[[Page 441]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.107
5.3.10 Daylight Credits for Skylights.
5.3.10.1 Skylights used in conjunction with automatic lighting
controls for daylighting can significantly reduce the lighting energy
consumption, thereby more than offsetting the increase in envelope heat
transfer.
[[Page 442]]
5.3.10.2 When determining building roof compliance, daylight
credits for skylights may be used if the criteria of this subsection are
met.
5.3.10.3 Skylights for which daylight credit is taken may be
excluded from the calculation of the overall thermal transmittance value
(Uor) of the roof assembly, if all of the following
conditions are met:
5.3.10.3.1 The opaque roof thermal transmittance Uor
value does not exceed the value determined within the selected Alternate
Component Package (ACP) table for the prescriptive method or by Equation
5.5-1 for the systems performance method.
5.3.10.3.2 Skylight areas, including framing, as a percentage of
the roof area do not exceed the values specified in Tables 5.3-6A and
5.3-6B for building sites located within the climate ranges listed in
the two Tables, where Visible Light Transmittance (VLT) is the
transmittance of a particular glazing material over the visible portion
of the solar spectrum. Skylight areas shall be interpolated between
visible light transmittance values of 0.75 and 0.50, only.
[[Page 443]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.108
[[Page 444]]
[GRAPHIC] [TIFF OMITTED] TC04OC91.109
5.3.10.3.3 The skylight area associated with daylight credit can be
taken is the area under each skylight whose dimension in each direction
(centered on the skylight) is equal to the skylight dimension in that
direction plus a distance equal to the floor to ceiling height.
5.3.10.3.4 Skylight areas that overlap areas that have already
taken daylight credit (perimeter window areas or other skylight areas)
do not again take daylight credit.
5.3.10.3.5 All electric lighting fixtures within skylight areas are
controlled by daylight-activated automatic lighting controls.
5.3.10.3.6 For buildings located in climates that have less than
8000 HDD65, the overall thermal transmittance of the skylight assembly,
including framing, is less than or equal to 0.7 Btu/hft \2\ deg.F. For
locations greater
[[Page 445]]
than 8000 HDD65, the overall thermal transmittance of the skylight
assembly, including framing, is less than or equal to 0.45 Btu/hft \2\
deg.F.
5.3.10.3.7 Skylight curbs have thermal transmittance (U) values no
greater than 0.21 Btu/hft \2\ deg.F.
5.3.10.3.8 The infiltration coefficient of the skylights does not
exceed 0.05 cfm/ft \2\.
5.3.10.4 Skylight areas in Tables 5.3-6A and 5.3-6B may be
increased by 50% if a shading device is used that blocks over 50% of the
solar gain during the peak cooling design condition.
5.3.10.5 Areas for vertical glazing in clerestories and roof
monitors shall be included in the wall fenestration calculation.
5.3.10.6 For shell buildings, the permitted skylight area from
Tables 5.3-6A and 5.3-6B shall be based on a light level of 30 fc and a
lighting power density (LPD) of less than 1 W/ft \2\.
5.3.10.7 For speculative buildings, the permitted skylight area
from Tables 5.3-6A and 5.3-6B shall be based on the unit lighting power
allowance from Table 3.4-1 and an illuminance level as follows:
5.3.10.7.1 For LPD less than or equal to 1.0 W/ft \2\, use 30 fc;
5.3.10.7.2 For LPD greater than 1.0 W/ft \2\ and less than 2.5 W/ft
\2\, use 50 fc; and
5.3.10.7.3 For LPD greater than 2.5 W/ft \2\, use 70 fc.
5.3.10.8 Buildings with roof assembly devices that cannot be
evaluated under this subsection shall be evaluated using the Building
Energy Compliance Methods of Section 11.0 or 12.0.
5.4 Building Envelope--Prescriptive Compliance Alternative
5.4.1 General.
5.4.1.1 This section provides a simple compliance path using
precalculated prescriptive requirements for selected exterior envelope
configurations of new buildings.
5.4.1.2 The Alternate Component Packages (ACP), found in this
subsection, provide design criteria for use with the following options:
5.4.1.2.1 ``Base Case''--buildings with envelopes designed without
perimeter daylighting.
5.4.1.2.2 ``Perimeter Daylighting''--buildings with envelopes that
use additional fenestration area by incorporating automatic lighting
controls in the perimeter zone to permit the use of daylighting in lieu
of electric lighting. This ACP is not available for those climates that
do not usually require space cooling by means of mechanical
refrigeration.
(a) This daylighting credit is in addition to the increased lighting
power allowance provided in section 3.5. Some perimeter daylighting
options allow a greater proportion of fenestration area due to the
increased visible and decreased thermal transmittances of high
performance glazings in combination with automatic lighting controls.
5.4.1.3 Each ACP provides a limited number of complying
combinations of building variables for a set of climate ranges. The
criteria, such as maximum percent fenestration, were calculated using
the system performance criteria of section 5.5. Values were chosen from
within climate and other variable ranges for the most restrictive
results, to ensure compliance of any combination of values within those
ranges. Thus, for most climate locations and envelope parameters, the
prescriptive criteria may be slightly more stringent than the system
performance criteria of section 5.5.
5.4.1.4 Both the base and perimeter daylight cases have two or
three fenestration U-value ranges depending on the climate.
5.4.2 Compliance.
5.4.2.1 The envelope design of the building being evaluated is in
compliance with the prescriptive criteria of this section provided that:
5.4.2.1.1 The minimum requirements of section 5.3 are met.
5.4.2.1.2 All envelope thermal transmittance (U) values are less
than or equal to those chosen from the ACP Table selected for roofs,
opaque walls, walls next to unconditioned spaces, and floors over
unconditioned spaces.
5.4.2.1.3 The percentage of fenestration of the combined gross wall
area is less than or equal to the value permitted for internal load
range and glazing in the selected ACP Table.
5.4.2.1.4 Slab-on-grade floors have insulation around the perimeter
of the
[[Page 446]]
floor with the thermal resistance (Ru) of the insulation as
listed in the ACP table. The slab insulation specified shall extend
either in a vertical plane downward from the top of the slab for the
minimum distance shown or downward to the bottom of the slab then in a
horizontal plane beneath the slab or outward from the building for the
minimum distance shown. The horizontal length, or vertical depth, of
insulation required varies from 24 in. to 48 in. depending upon the R-
value selected. For heated slabs, an R of 2 shall be added to the
thermal resistance required.
(a) Vertical insulation shall not be required to extend below the
foundation footing.
(b) There are no insulation requirements for slabs in locations
having less than 3,000 HDD65 or for footings extending less than 18 in.
below grade.
5.4.2.1.5 The thermal resistance of the below-grade wall assembly
must be greater than or equal to that listed in the ACP table, or the
heat loss calculated in accordance with Chapter 25 of the ASHRAE
Handbook, 1985 Fundamentals shall be less than or equal to that of a
wall below grade having a thermal resistance equal to that specified in
Figure 5.5-3. No insulation is required for climates with less than
3,000 HDD65 or for those portions of walls more than one story below
grade.
5.4.3 Procedure for Using the Alternate Component Packages (ACP).
5.4.3.1 The prescriptive envelope criteria for each of 30 climate
ranges are contained in Tables 5.4-2 through 5.4-31.
5.4.3.2 The following steps shall be used to determine compliance
with these prescriptive envelope criteria.
5.4.3.2.1 Determine appropriate climate range using either (a) or
(b) below.
(a) From Table 5.4-1, select the appropriate ACP Table based on the
climate for the building site. The main climate variables that are
needed for the proper selection of an ACP Table are cooling degree-days
base 65 deg.F (CDD65), heating degree-days base 50 deg.F (HDD50), and
annual average daily incident of solar radiation on the east or west
vertical surface of the facade, Btu/ft\2\/day (VSEW). For certain
climate ranges this must be augmented by cooling degree-hours base 80
deg.F (CDH80).
(1) This data, for a specific building location, may be acquired
from the U.S. Weather Service of the National Oceanic and Atmospheric
Administration or the local weather bureau. The column designated ``ACP
Table No.'' in Table 5.4-1 contains the table number of the appropriate
ACP Table.
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(b) From the list of cities in Appendix 5A, ``List of Cities and
Climate Data'', which contains data for 234 cities, select the closest
city climatologically to the building site. If the site is not one of
the cities listed or if the climate at the site differs significantly
from a listed adjacent city, obtain the information from the weather
bureau or other reliable source and use (a) above. The column designated
``ACP Table No.'' contains the table number of the appropriate ACP
Table.
(c) For information purposes only, the climate data used to develop
the ACP tables for the above-grade wall section are shown in Table 5.4-
32. The criteria for all other envelope sections was based on the most
stringent level for the cities listed in the ACP Table.
5.4.3.2.2 Determination of Maximum Allowable Percent Fenestration.
(a) Using the appropriate ACP Table, determine the maximum allowable
percent fenestration. The maximum allowable percent fenestration is the
[[Page 509]]
total area of fenestration assemblies divided by the total gross
exterior wall area, considering all elevations of the building.
Determining the maximum allowable percent fenestration requires the
following five steps:
(1) Based on the Internal Load Density (ILD) for the proposed
design, select one of the three Internal Load Ranges as the point of
entry to the tables. Note for ILD's greater than 3.5 W/ft \2\ use the
3.5 W/ft \2\ range. For shell buildings, see procedures in Section
5.3.8. Determine the ILD of the proposed design, based on the sum of the
Internal Lighting Power Allowance (ILPA), the Equipment Power Density
(EPD) and Occupant Load Adjustment (OLA), as shown in Equation 5.4-1.
ILD=ILPA+EPD+OLA
Equation 5.4-1
Where:
The Internal Lighting Power Allowance (ILPA) shall be:
1. The building average Internal Lighting Power Allowance (ILPA) of
the design building in W/ft \2\ as determined in Section 3.4 or 3.5;
2. The average of the Lighting Power Budgets (LPB) for all activity
areas within 15 ft of each exterior wall based on the procedures
specified by the Systems Performance Criteria of Section 3.5.3, or
3. The actual lighting power density of the proposed design in W/ft
\2\, either the building average or the average of the lighting power
within 15 ft of each exterior wall.
Note.-- The lighting prescriptive path, Section 3.4, does not
provide lighting values for health, assembly, multi-family high rise,
and hotel/motel buildings type occupancies. Use the 1.51 to 3.0 range of
Internal Load Density for health and assembly buildings; and the 0 to
1.5 range for multi-family high rise and hotel/motel buildings.
The Equipment Power Density (EPD) shall be either:
1. The building average receptacle power density selected from Table
5.4-33 in W/ft \2\; or
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2. The actual average receptacle power density for all activity
areas within 15 ft of each exterior wall in W/ft \2\, considering
diversity. For determining compliance in Tables 5.4-2 through 5.4-31,
the actual average receptacle power densities calculated by this method
that exceed 1.0 W/ft \2\ shall be limited to 1.0 W/ft \2\ in Equation
5.4-1.
The Occupant Load Adjustment (OLA) shall be either:
1. 0.0 W/ft\2\. This recognizes the assumed occupant sensible load
of 0.6 W/ft\2\ that is built into the ACP tables; or
2. A positive or negative difference between the actual occupant
load and 0.6 W/ft\2\ if the design building has a larger or smaller
occupant load.
(2) Select external shading projection factor (PF). If no external
shading projections are used in the proposed design, select the column
designated Projection Factor=0.000-0.249. If external shading
projections are used, determine the average area weighted projection
factor on the window in accordance with Equation 5.4-2. Then select the
appropriate column in the ACP Table.
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Equation 5.4-2
Where:
PF=Average area weighted projection factor
Pd=External horizontal shading projection depth, in. or ft
H=Sum of height of the fenestration and the distance from the top of the
fenestration to the bottom of external shading projection in
units consistent with Pd.
[[Page 511]]
(3) Select the Shading Coefficient of the fenestration
(SCx) including internal, integral, and external shading
devices, but excluding the effect of external shading projections (PF).
This includes curtains, shades, or blinds. Reference ASHRAE Handbook,
1985 Fundamentals Volume, Chapter 27.
(4) Select one of the daylighting options, either:
1. Base Case, no daylighting; or
2. Perimeter Daylighting (automatic daylight controls for lighting
system must be used). This option is not available in some locations.
(5) Select appropriate fenestration type. For most options, this is
determined by the thermal transmittance value (Uof) of the
fenestration assembly. For some fenestration options, the visible light
transmittance (VLT) of the fenestration should not be less than the
shading coefficient of the glazed portion of the fenestration assembly,
not considering any shading devices. The ranges generally correspond to
single glazing, double glazing, triple glazing and high performance
glazing incorporating low emissivity coatings/films or more than two
glazing layers. Each ACP table includes at most, three ranges of glazing
U-value.
5.4.4.2.3 Determine the Maximum Uow for the Opaque Wall
Assembly. In the appropriate ACP Table the Maximum Uow for
the opaque wall assembly is determined using the following steps:
(a) For a lightweight wall assembly, heat capacity (HC) less than 5
Btu/ft\2\ deg.F, use the value indicated. This Uow is
constant over all internal load ranges.
(b) To use the mass wall adjustment, the following additional steps
are necessary:
(1) Select the same internal load range as that used in determining
the maximum allowable percent fenestration.
(2) Select the mass wall heat capacity (HC) and insulation position.
If the wall insulation is positioned internal to or integral with the
wall mass, use the column headed Interior/Integral Insulation. If the
wall insulation is positioned external to the wall mass use the column
headed Exterior Insulation. For HC less than 5 Btu/ft\2\ deg.F this
adjustment table cannot be used. At this step you will have two choices
of Uow that are keyed to a small or large percent
fenestration. This represents the full range of Uow values
allowed.
(3) Select or interpolate the appropriate maximum Uow for
the opaque wall based on the maximum allowable percent fenestration
determined in Section 5.4.4.2.2 or the actual building percent
fenestration whichever value is lower. The Uow shall be
determined by straight line interpolation for fenestration percentages
between the smallest and largest values listed. If the design building
percentage fenestration is less than the smallest value listed, select
the Uow for the largest percentage fenestration listed.
5.4.4.2.4 Determine Other Envelope Criteria. In each ACP table, the
criteria for roof, wall adjacent to unconditioned space, wall below
grade (first story only), floor over unconditioned space, and slab-on-
grade floors, shall be met. For heated slabs on grade, the R-value shall
be the R-value for the unheated slab-on-grade plus 2.0. For skylights,
the daylight credit procedure presented in Section 5.3.10 shall be used.
5.5 Building Envelope--System Performance Compliance Alternative
5.5.1 Roof Thermal Transmittance Criteria
5.5.1.1 Any building that is heated and/or mechanically cooled
shall have an overall thermal transmittance value (Uor) for
the gross area of the roof assembly not greater than the value
determined by Equation 5.5-1. The provisions of Section 5.3 shall be
followed in determining acceptable combinations of materials that will
meet the required Uor values of Equation
5.5-1.
Uo=1/
(5.3+1.8 x 10-\3\ x HDD65+1.3 x 10-3
x CDD65+2.6 x 10-4 x CDH80)
Equation 5.5-1
5.5.1.2 Equation 5.5-1 applies only for climate locations with
HDD65 less than or equal to 15,000. For climate locations with HDD65
greater than 15,000, see subsection 5.3.9, Table 5.3-5.
5.5.1.2.1 Exceptions to Section 5.5.1.2:
(a) any building that is only heated shall have an overall thermal
transmittance value (Uor) for the gross area of
[[Page 512]]
the roof assembly less than or equal to the value determined by Equation
5.5-1 with CDD65 and CDH80 set equal to zero; and
(b) any building that is only mechanically cooled shall have an
overall thermal transmittance value (Uor) for the gross area
of the roof assembly less than or equal to the value determined by
Equation 5.5-1 with HDD65 set equal to zero.
5.5.2 Floor Thermal Transmittance Criteria
5.5.2.1 The floors of any building that is heated and/or
mechanically cooled shall meet the following thermal criteria:
5.5.2.1.1 Floors of conditioned spaces over unconditioned spaces
shall have a thermal transmittance (Uof) not greater than
that specified in Figure 5.5-1.
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5.5.2.1.2 Slab-on-grade floors shall have insulation around the
perimeter of the floor with the thermal resistance (Ru) of
the insulation as specified in Figure 5.5-2. The insulation specified in
Figure 5.5-2 shall extend either in a vertical plane downward from the
top of the slab for the minimum distance shown or downward to the bottom
of the slab for the minimum distance shown then in a horizontal plane
beneath the slab. The horizontal length, or vertical depth, of
insulation required varies from 24 in. to 48 in. depending upon the R-
value selected. For heated slabs, an R of 2 shall be added to the
thermal resistance required in Figure 5.5-2.
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(a) Vertical insulation is not required to extend below the
foundation footing. There are no insulation requirements for slabs in
locations having less than 3,000 HDD65 for footings extending less than
18 in. below grade.
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5.5.3 Thermal Transmittance Criteria For Opaque Walls Enclosing
Conditioned Spaces Exposed to Interior Unconditioned Spaces
5.5.3.1 All opaque walls enclosing conditioned spaces exposed to
interior unconditioned spaces shall have an overall thermal
transmittance (Uow) not greater than the value specified in
Figure 5.5-3.
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5.5.4 Thermal Resistance Criteria for Exterior Wall Insulation Below
Grade
5.5.4.1 The thermal resistance (R) of the wall assembly shall be
greater than, or equal to the insulation level specified in Figure 5.5-
4, or the heat loss calculated in accordance with Chapter 25 of the
ASHRAE Handbook, 1985 Fundamentals Volume shall be less than, or equal
to that of a wall below grade having a thermal resistance equal to that
specified in Figure 5.5-4. No insulation is required for climate
locations with less than 3,000 HDD65 for those portions of walls more
than one story below grade.
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5.5.5 External Wall Criteria for Heating and Cooling
5.5.5.1 The external wall heating criteria (WCh) and
cooling criteria (WCc) represent limits on cumulative annual
heating and cooling energy flux attributable to transmission and solar
gain. These limits accommodate variation in internal load and wall heat
capacity. They shall be determined for a building envelope design using
Equations 5.5-2 and 5.5-6 in Attachment 5B, ``Equations to Determine
External Wall Heating and Cooling Criteria (WCc and
WCh) and to Determine Compliance (Ci and
Hi) With the Criteria.''
5.5.6 Wall Heating and Cooling Compliance Values
5.5.6.1 The wall heating compliance value Hi and the
wall cooling compliance value Ci are estimates of the
cumulative annual heating and cooling energy flux attributable to heat
transmission and solar gains. These estimates consider the effects of
variations in internal load and wall heat capacity. They shall be
calculated using Equations 5.5-2 and 5.5-6 in Attachment 5B.
5.5.6.3 Applying the Criteria
5.5.6.3.1 The wall criteria shall be applied as follows:
(a) For all buildings that are heated and mechanically cooled, the
sum of the calculated wall heating and cooling compliance values,
Hi and Ci, for all orientations of the proposed
design, as determined in section 5.5.6, shall not exceed the sum of the
corresponding wall criteria for all orientations for wall heating
(WCh) and wall cooling (WCc).
(b) For buildings that are only heated, the sum of the calculated
wall heating compliance values, Hi, for all orientations of
the proposed design, as determined in section 5.5.6, shall not exceed
the sum of the corresponding wall heating criterion WCh for
all orientations.
(c) For buildings that are only mechanically cooled, the sum of the
calculated cooling compliance values, Ci, for all
orientations of the proposed design, as determined from section 5.5.6,
shall not exceed the sum of the corresponding wall cooling criteria,
WCc for all orientations.
5.5.6.4 Constraints on Thermal Transmittance Values
5.5.6.4.1 The compliance calculation procedure in section 5.5.6.3
allows great flexibility in selecting values for envelope components as
long as the overall criteria are met. In calculating compliance, two
constraints are imposed on thermal transmittance values for opaque wall
assemblies and fenestration assemblies comprising the Uo
term, as follows:
(a) Opaque Wall Assemblies: The opaque portion of walls with heat
capacity (HC) less than 7 Btu/ft2 deg.F shall have an
overall thermal transmittance (Uow) not greater than the
value specified in Figure 5.5-4. Procedures, specified in section 5.3,
shall be used to determine acceptable combinations of materials that
meet the required value.
(b) Fenestration Assemblies: The overall thermal transmittance
(Uof) of fenestration assemblies shall not exceed 0.81 Btu/
hft\2\ deg.F for all locations with more than 3000 HDD65 if the
fenestration area exceeds 10% of the total wall area exposed to the
outside air. Thermal transmittance for the fenestration shall be
determined using the calculation procedures in Section 5.3.1 and shall
include the effects of sash, frames, edge effects, and spacers for
multiple-glazed units.
5.5.6.5 Constraint on Daylighting Credit
5.5.6.5.1 For a given orientation, daylight credit may be used in
Equations 5.5-2 and 5.5-6 only for that portion of the fenestration that
is less than or equal to 65% of the gross wall area of the orientation.
5.5.6.6 Lighting Power Density
5.5.6.6.1 The Lighting Power Density used in calculating the
compliance value shall be:
(a) The building average unit Interior Lighting Power Allowance of
the proposed design in W/ft\2\ as specified in section 3.0;
(b) The average of the Lighting Power Budgets for all activity areas
within 15 ft of each exterior wall based
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on the procedures set forth in section 5.3; or
(c) The actual lighting power density of the proposed design in W/
ft\2\, either building average or average of the lighting power within
15 ft of each exterior wall.
5.5.6.7 Equipment Power Density
5.5.6.7.1 The equipment power density used in determining
compliance shall be either:
(a) The ``Average Receptacle Power Densities'' from Table 5.4-32, or
(b) The actual average Equipment Unit Power Density, considering
diversity, either building average or average in the activity areas
within 15 ft of each exterior wall, not to exceed 1 W/ft\2\.
5.5.6.8 Occupancy Loads
5.5.6.8.1 An occupancy load of 0.6 W/ft\2\ is assumed. If the
occupancy loads in the building design are different from this value,
use the larger value.
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Attachment 5C to 435.105 Bibliography
1. Pacific Northwest Laboratory. October, 1983. Recommendations for
Energy Conservation Standards and Guidelines for New Commercial
Buildings. For Building System Division, Assistant Secretary,
Conservation and Renewable Energy, U.S. Department of Energy. (Contract
No. DE-AC06-76RLO 1830). The report is issued in 4 volumes consisting of
40 separate publications (PNL-4870-1 through PNL-4870-40). The
publications most pertinent to the envelope analysis are cited below:
Volume 2: Description of the Development Process; Appendix A:
Envelope Research Documentation.
Volume 3: Description of the Testing Process; Appendix B: Envelope
Compliance Code Documentation.
Volume 4: Documentation of Test Results: (Each in 3 volumes): A:
Small Office Building (Branch Bank); B: Medium Office Building; C: Large
Office Building; D: Retail Store (Anchor Store); E: Strip Store; F:
Apartment House; G: Hotel; H: Warehouse; I: Assembly Building (Church);
J: School.
2. Jones, Jerold, W., Special Project 41: ``Development of
Recommendations to Upgrade ASHRAE Standard 90A-1980. `Energy
Conservation in New Building Design' '', ASHRAE Journal. October, 1983.
3. Wilcox, B., A. Gumerlock, C. Barnaby, R. Mitchell, and C.
Huizenga, Berkeley Solar Group. December 1985. ``The Effects of Thermal
Mass Exterior Walls on Heating and Cooling Loads in Commercial
Buildings: A Procedure for Calculations in ASHRAE Standard 90.''
Proceedings, Thermal Performance of the Exterior Envelopes of Buildings
III. ASHRAE/DOE/BTECC, pp 1187-1224, Clearwater Beach, Florida.
4. Hirsch, James J. December 1982. ``Simulation of HVAC Equipment in
the DOE-2 Program.'' Energy and Environment Division, Lawrence Berkeley
Laboratory, University of California. LBL-14026. DOE Contract DE-AC03-
76SF00098.
5. Johnson, R., D. Arasteh, D. Connell and S. Selkowitz. ``The
Effect of Daylighting Strategies on Building Cooling Loads and Overall
Energy Performance.'' Windows and Daylighting Group, Lawrence Berkeley
Laboratory, University of California. LBL-20374.
6. D. Arasteh, R. Johnson, S. Selkowitz and D. Connell. September
1985. ``Cooling Energy and Cost Savings with Daylighting in a Hot and
Humid Climate.'' Applied Science Division, Lawrence Berkeley Laboratory,
University of California. LBL-19734. DOE Contract DE-AC03-76SF00098.
7. Sullivan, R., Y.J. Huang, J. Bull, I. Turiel, R. Ritschard and S.
Selkowitz. April 1985. ``Thermal Analysis of Buildings--Configuration
Perturbations and Observed Climate Interface.'' Applied Science
Division, Lawrence Berkeley Laboratory, University of California. LBL-
19383. DOE Contract DE-AC03-76SF00098. ASHRAE Transactions, Vol. 92,
Part 1, 1986.
8. Johnson, R., D. Arasteh, and S. Selkowitz. March, 1985. ``Energy
Reduction Implications of Fenestration,'' Applied Science Division,
Lawrence Berkeley Laboratory, University of California. LBL-19304. DOE
Contract DE-AC03-76SF00098.
9. Selkowitz, S. October 1984. ``Influence of Windows on Building
Energy Use.'' Applied Science Division, Lawrence Berkeley Laboratory,
University of California. LBL-18663. DOE Contract DE-AC03-76SF00098.
10. Johnson, R., R. Sullivan, S. Selkowitz, S. Nozaki, C. Conner and
D. Arasteh. 1984. ``Glazing Energy Performance and Design Optimization
with Daylighting.'' Energy and Buildings, 6 (1984) pp. 305-317.
11. Selkowitz, S., D. Arasteh, and R. Johnson. July 1984. ``Peak
Demand Savings from Daylighting in Commercial Buildings.'' Applied
Science Division, Lawrence Berkeley Laboratory, University of
California. LBL-18126. DOE Contract DE-AC03-76SF00098.
12. Johnson, R., S. Selkowitz, and R. Sullivan. April 1984. ``How
Fenestration Can Significantly Affect Energy Use in Commercial
Buildings.'' Energy Efficient Buildings Program, Lawrence Berkeley
Laboratory, University of California. LBL-17330. DOE Contract DE-AC03-
76SF00098.
13. Sullivan, R., S. Nozaki, R. Johnson, and S. Selkowitz. October
1983. ``Commercial Building Energy Performance Analysis Using Multiple
Regression Procedures.'' Applied Science Division, Lawrence Berkeley
Laboratory, University of California. LBL-16645. DOE Contract DE-AC03-
76SF00098.
14. September 1983. ``Data Base Definition and Procedural Guidelines
for Building Envelope Thermal and Daylighting Analysis in Support of
Recommendation to Upgrade ASHRAE/IES Standard 90.'' Applied Science
Division, Lawrence Berkeley Laboratory, University of California. LBID-
801. DOE Contract DE-AC03-76SF00098.
15. Johnson, R., R. Sullivan, S. Nozaki, S. Selkowitz, C. Conner,
and D. Arasteh. September 1983. Building Envelope Thermal and
Daylighting Analysis In Support of Recommendations to Upgrade ASHRAE/IES
Standard 90--Final Report. Applied Science Division, Lawrence Berkeley
Laboratory, University of California. LBLl-16770. DOE Contract DE-AC03-
76SF00098.
16. Selkowitz, S., S. Choi, R. Johnson and R. Sullivan. 1983. ``The
Impact of Fenestration on Energy Use and Peak Loads in Daylighted
Commercial Buildings.'' Progress in Passive Solar Energy Systems,
Copyright 1983. (0731-8626/83).
17. Choi, S., R. Johnson and S. Selkowitz. 1984. ``The Impact of
Daylighting on Peak Electrical Demand.'' Energy and Buildings, 6 (1984)
pp. 387-399.
[[Page 549]]
18. Selkowitz, S. and F. Winkelmann. May 1983. ``New Models for
Analyzing the Thermal and Daylighting Performance of Fenestration.''
Energy Efficient Buildings Program, Lawrence Berkeley Laboratory,
University of California. LBL-14517. DOE Contract DE-AC03-76SF00098.
19. Selkowitz, S., J. J. Kim, M. Navvab and F. Winkelmann. June
1982. ``The DOE-2 and Superlite Daylighting Programs.'' Applied Science
Division, Lawrence Berkeley Laboratory, University of California. LBL-
14569. DOE Contract DE-AC03-76SF00098.
20. Johnson, R., S. Selkowitz, F. Winkelmann, and M. Zenter. October
1981. ``Glazing Optimization Study for Energy Efficiency in Commercial
Office Buildings.'' Energy Efficient Buildings Program, Lawrence
Berkeley Laboratory, University of California. LBL-12764. DOE Contract
DE-AC03-76SF00098.
21. Arasteh, D., Johnson, R., Selkowitz, S., and Sullivan R. 1985.
``Energy Performance and Savings Potential with Skylights.'' ASHRAE
Transactions, Vol. 91, Part 1.
22. Arasteh, D., Johnson, R., and Selkowitz, S. May 1985. The
Effects of Skylight Parameters on Daylighting Energy Savings, Applied
Science Division. Lawrence Berkeley Laboratory, University of
California, LBL-17456. DOE Contract DE-AC03-76SF00098.
23. Crawley, D.B., Briggs, R.S., December 1985. Envelope Design
Implications of ASHRAE Standards 90.1P: A Case Study View, Proceedings,
Thermal Performance of the Exterior Envelope of Buildings III, ASHRAE/
DOE/BTECC, Clearwater Beach, FL. Pacific Northwest Laboratory, Richland,
WA. DOE Contract DE-AC06-76RLO-1830.