This document provides an introduction to California Title 24 standards regarding windows, lighting, and ventilation. It discusses the history of window glass and fenestration technology. It also summarizes key Title 24 requirements, including maximum window U-factors and SHGC values by climate zone. Fenestration is classified into types 1-3 depending on manufacturing method. Default values from tables 116-A and 116-B are used for some fenestration when NFRC labels are unavailable.
3. California Center for Sustainable Energy
Wi d
Windows, Li hti d
Lighting and
Ventilation
Welcome and Window Basics
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4. California Center for Sustainable Energy
Presenters:
Douglas Beaman,
Gary Wollin
608 - 13th Street
Modesto, California 95354
doug@dougbeaman.com
gary@dougbeaman.com
(209) 524-1000
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January 1, 2010
Any building permit applied for on or after January 1
1,
2010 must comply with the new Standards.
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Available in PDF format from
the CEC website:
Publication #:
CEC-400-2008-001-CMF
The Standards contain the
actual code language,
harder to understand
understand,
but the last word.
www.energy.ca.gov/title-24
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Available in PDF format
from the CEC website:
Publication #:
CEC-400-2008-016-CMF
Designed to be used by
building departments,
builders,
builders energy
consultants.
www.energy.ca.gov/title24
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The word fenestration finds its root in the Latin word for
window, fenestra.
Architecture
Products that fill openings in a building envelope, such
as windows, doors, skylights, curtain walls, etc.,
designed to permit the passage of air, light, vehicles,
or people.
l
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Almost no homes enjoyed the benefits of
insulation. Homes either had mass,
stone walls, sod or logs, were timber
ll d l i b
framed with possibly some straw or mud
in the voids.
For many glass was an expensive luxury.
Well into the 19th century glass was
expensive and many homes had double
shutters.
Homes were naturally ventilated. Summer
and Winter.
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Homes for millennia had heating that was provided by a
fireplace.
In f t th E gli h
I fact the English word for window does not come from a
df i d d t f
hole in a wall but a hole in the roof that the Vikings used
to allow the smoke out of a building.
Origin:
1175–1225; Middle English windoge, windowe
Old Norse vindauga equiv to vindr = wind + auga = eye
vindauga, equiv.
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Window glass, in use since the 1st century AD, was originally made by
casting, or by blowing hollow cylinders that were slit and flattened
into sheets
sheets.
The term glass developed in the late Roman Empire. It was in the
Roman glassmaking center at Trier, now in modern Germany, that
the late-Latin term glesum originated, probably from a Germanic
word for a transparent, lustrous substance.
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The crown process was a later technique, in which a gather of
glass was blown and shaped into a flattened globe or crown.
The
Th pontil rod was attached to the flat side, the blowpipe
il d h d h fl id h bl i
removed. By spinning the reheated crown on the rod, the
hole left by the blowpipe enlarged, and eventually the disk,
through centrifugal force, flapped out in a large circular
sheet. The pontil rod was cracked off, leaving a scar, or
bull's-eye.
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1834, Robert Lucas Chance introduced "Improved
Cylinder Sheet" glass which was produced using a
process invented in Germany. This produced even
finer and larger glasses. This was the glass used to
glaze the "Crystal Palace" in London.
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Today, nearly all window glass is made mechanically
by drawing g
y g glass upward from a molten p
p pool fed
from a tank furnace.
In the Fourcault process the glass sheet is drawn
through a slotted refractory block submerged in
the surface of the glass pool, into a vertical
annealing furnace from which it emerges to be
cut into sheets.
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The new glass provides a vacuum space between two panes of glass. To
keep the two sheets of glass from being drawn together by the vacuum,
low thermal-conductivity spacers are placed in the space between the
two panes. (These are the small dots that can be seen in the
photograph.)
The vacuum is only about 1/100th as strong as what is typically found in an
ordinary thermos, it is still far better than
standard double pane glass in preventing
heat loss from conduction and from
convection. The only other glazing systems
I have come across with close to this level of
insulation value have been nanogel-filled
windows, but those are just translucent,
and do not allow clear vision through the
glass.
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U-Factor
SHGC (Solar
SHGC—(Solar Heat Gain Coeffieicnt)
AL—(Air Leakage)
VT—Visible Light Transmittance
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A measure of the rate of non-solar heat flow through a
material or assembly. The lower the U-factor, the
greater a window’s resistance to heat flow and the
better its insulating value. The U-factor is the
reciprocal of the R-value (U=1/R).
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The fraction of solar radiation transmitted through a
window, expressed as a percentage. The lower a
window s SHGC,
window’s SHGC the less solar heat it transmits
and the greater its shading ability. Generally, a
lower SHGC is desirable in warm climates, and a
higher SHGC in cold ones.
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Heat loss and gain occur by infiltration through
cracks in the window assembly. It is indicated by
y y
an air leakage rating (AL) expressed as the
equivalent cubic feet of air passing through a
square foot of window area. The lower the AL, the
less air will pass through cracks in the window
assembly.
assembly At this time, the AL is optional.
time optional
Select windows with an AL of 0.30 or less (units are
cfm/sq ft).
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The visible transmittance (VT) is an optical property
that indicates the amount of visible light
transmitted.
transmitted The NFRC's VT is a whole window
rating and includes the impact of the frame
which does not transmit any visible light. While
VT theoretically varies between 0 and 1, most
values are between 0.3 and 0.8. The higher the
VT, the more light is transmitted. A high VT is
desirable t
d i bl to maximize d light
i i daylight.
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An Insulating Glass Unit is the transparent
component of a window or door assembly. An IGU
p y
comprises two or three panes of glass separated
with spacers and sealed at the edges. IGU also
includes the insulating air space between the
panes. Often this air space is replaced with a
gas-fill.
gas fill
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Single-Glazed with Clear Glass
Relative to all other glazing
options, single-glazed with
clear glass allows the
highest transfer of energy
(i.e. heat loss or heat gain
depending on local climate
p g
conditions) while permitting
the highest daylight
transmission.
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Originally, the space was filled with air or flushed with dry nitrogen just prior to sealing.
In a sealed glass insulating unit, air currents between the two panes of glazing carry heat to
the top of the unit and settle into cold pools at the bottom. Filling the space with a less
conductive, more viscous, or slow-moving gas minimizes the convection currents within
the space, conduction through the gas is reduced, and the overall transfer of heat
between the inside and outside is reduced.
Argon is inexpensive, nontoxic, nonreactive, clear, and odorless. The optimal spacing for an
argon-filled unit is the same as for air, about 1/2 inch (11-13 mm).
Krypton has better thermal performance, but is more expensive to produce. Krypton is
particularly useful when the space between glazings must be thinner than normally
desired, for example, 1/4 inch (6 mm). The optimum gap width for krypton is 3/8"
3/8
(9mm).
A mixture of krypton and argon gases is also used as a compromise between thermal
performance and cost.
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Low-emittance (Low-E) coating are microscopically thin, virtually invisible,
metal or metallic oxide layers deposited on a window or skylight glazing
surface primarily to reduce the U-factor by suppressing radiative heat
U factor
flow.
The principal mechanism of heat transfer in multilayer glazing is thermal
radiation from a warm pane of glass to a cooler pane. Coating a glass
surface with a low-emittance material and facing that coating into the
gap between the glass layers blocks a significant amount of this radiant
heat transfer, thus lowering the total heat flow through the window.
Low-E coatings are transparent to visible light. Different types of Low-E
coatings have been designed to allow for high solar gain, moderate
solar gain, or low solar gain.
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One approach to reducing heat loss has been to replace the aluminum spacer with a metal
that is less conductive, e.g. stainless steel, and change the cross-sectional shape of the
spacer.
Another approach is to replace the metal with a design that uses materials that are better
insulating. The most commonly used design incorporates spacer, sealer, and desiccant
in a thermoplastic compound that contains a blend of desiccant materials and
incorporates a thin, fluted metal shim of aluminum or stainless steel.
Another approach uses an insulating silicone foam spacer that incorporates a desiccant and
has a high-strength adhesive at its edges to bond to glass. The foam is backed with a
secondary sealant. Both extruded vinyl and fiberglass spacers have also been used in
place of metal designs.
For purposes of determining the overall window U-factor, the edge spacer has an effect that
extends beyond the physical size of the spacer to a band about 2-1/2 inches wide. The
contribution of this 2-1/2-inch-wide "glass edge" to the total window U-factor depends
on the size of the window. Glass edge effects are more important for smaller windows,
which have a proportionately larger glass edge area.
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Back to California
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§151(f)3 and 4 have the prescriptive requirements for
fenestration in low-rise residential buildings. These
include requirements for maximum glazing area,
maximum U-factor, and for some climate zones, a
maximum SHGC requirement.
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Window values:
U-factors from 0.55 – 0.67 to 0.40
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§151(f)3 Exception allows up to 3 square feet of the
glazing installed in doors and up to 2 square feet of
tubular skylight with dual-pane diffusers to have an
assumed U-factor equivalent to the Package
requirements.
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Type 1
Manufactured products are delivered pre-assembled
pre assembled
from the factory.
This is the most common type of fenestration in
residential construction.
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Type 2
Site built
Site-built products are glazed or assembled on site
using factory prepared systems. . . . For unlabeled
site-built fenestration use default values from
Standards Table 116-A for U-factor and Table 116-B
for SHGC, otherwise, select site-build fenestration
from NFRC’s Certified Products Directory
NFRC s Directory.
See http://www.NFRC.org.
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Type 3
Field fabricated
Field-fabricated products are built on site using
standard dimensional lumber or other materials not
intentionally prepared for use as a fenestration
product. For field-fabricated fenestration use default
values from Standards Table 116-A for U-factor and
Table 116-B for SHGC
116 B SHGC.
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Answer
For glass block, use the U-factor and SHGC values from Standards Tables
116-A and 116-B for the frame type in which the g
yp glass blocks are
installed.
The worst-case scenario would be a metal-framed glass.
The U-factor for metal framed glass block is from Table 116-A is therefore
0.87.
The SHGC depends on whether the glass block has a metal or non-metal
frame, and is operable or fixed or clear or tinted.
For this example, the glass block is operable and clear, therefore the S GC
f SHGC
is 0.70.
Glass block is considered a field-fabricated product and therefore does not
need a label.
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Doors with less than 50% glass areas are treated as
a door with fenestration installed within the door.
The glass area is calculated as the sum of the glass
areas plus two inches on all sides (to account for
framing).
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The NFRC label if one is available, or
The default values from Standards Table 116-A and
116-B.
The opaque part of the door is ignored in the prescriptive
approach. If the performance approach is used for the
glazing part of the door, an NFRC label or default values
for U-factors and SHGC must be used, for the opaque
portion of the door, a default value of 0.50 must be
assumed.
assumed
Alternatively, if available, NFRC values for U-factor and SHGC
may be used for the entire door, including the opaque
areas.
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I plan on installing a tubular skylight using the
performance approach. The skylight has a clear
plastic dome exterior to the roof, a single pane 1/4.-
in. (6 mm)-thick acrylic diffuser mounted at the
ceiling, and a metal tube connecting the two.
How do I determine the U-factor and SHGC that I will
need to comply with the Standards?
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Method 1
Use the default U-factor from Standards Table 116-A
116-A.
This tubular skylight would be considered a metal
frame, fixed, single-pane resulting in a U-factor of
1.19, which must appear on a label preceded by the
words “CEC Default U-factor.”
(A tubular skylight would have to have two panes of
glazing with an air space of less than two inches
(50 mm) between them at the plane of the ceiling
insulation for it to be considered double-pane.)
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Method 2
Determine the U-factor from the Reference
U factor
Nonresidential Appendix NA6, Equation NA6-1.
The U-factor for this tubular skylight is based on the
metal with no curb (Table NA-1).
The U-factor for this skylight using Equation NA6-1 is 1.25, where Ut =
(0.195 + (0.882 x 1.20)).
This must appear on a label stated as:
“CEC Default U-factor 1.25.”
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Method 3
If the skylight has been tested and certified pursuant to
NFRC procedures, then use the NFRC label that
states, “Manufacturer stipulates that this rating was
determined in accordance with applicable NFRC
procedures NFRC 100” followed by the U-factor.
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How would the U-factor and the SHGC be determined if
the skylight in the example above has a dual pane
diffuser (instead of single pane) mounted at the
ceiling?
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The procedure would be exactly the same as the
example above, except that double pane U-factor
and SHGC values from Standards Tables 116-A and
116-B would be used instead of single pane values.
Note: Up to 2 square feet of tubular skylight is assumed
to have the U-factor required to meet prescriptive
compliance or the Package D value for performance
compliance (Exception to §151(f)3A).
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There is no credit for interior shading devices, although
they can be effective in reducing solar gains and
should be considered by homeowners.
The Energy Commission considers interior shades in
the category of home furnishings and not a feature
of the house that is provided by the builder.
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The field inspector should verify that the windows
and other fenestration products installed have
performance characteristics that are
documented on the temporary NFRC labels and
that comply with the U-factor and SHGC used in
the compliance documentation, including the
CF-6R. All fenestration products must have a
temporary label indicating U f t SHGC, and air
t l b l i di ti g U-factor, SHGC d i
infiltration rate (only field-fabricated products are
exempt from labeling requirements).
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The heat transfer characteristics of site-built curbs are
not included in the NFRC rating and must be
modeled as a part of the opaque building envelope.
For compliance purposes with the low-rise residential
standards, the U-factor for a skylight rated with any
of the three mounting variations described above is
applied to the area of the rough opening
opening.
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1. Inset mount, where the curb of the skylight extends into
the rough opening on the roof;
2. Curb mount, where the outside of the curb is equal to
the rough opening in the roof; and
3. Curb mount, where the inside of the curb is equal to the
rough opening in the roof.
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The heat transfer characteristics of site-built curbs are
not included in the NFRC rating and must be
modeled as a part of the opaque building envelope.
For compliance purposes with the low-rise residential
standards, the U-factor for a skylight rated with any
of the three mounting variations described above is
applied to the area of the rough opening
opening.
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Advisory: New Year, New Numbers
As of January 4, 2010, ENERGY STAR qualified windows, doors, and
skylights will meet new performance levels
levels.
In the next few months, you will see two new labels to help you choose
windows, doors, or skylights for your home:
Starting October 1, 2009, you might see the label, in red or in
black, in combination with ENERGY STAR product labels.
This label identifies high-efficiency products that currently
qualify for the ENERGY STAR but will not meet the more
stringent requirements that go into full effect April 1, 2010.
Another new label helps you find products that are
eligible for the federal tax credit of up to $1,500. The
label to the left, already visible in stores today, tells
you the product qualifies for ENERGY STAR and is
also eligible for the tax credit.
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Answer
Yes, there is a tax credit for storm windows and doors in 2009 and
2010 that meet this criteria:
Storm Window.
A storm window that, in combination with the exterior window over
which it is installed-
1. Has a U-factor and SHGC of 0.30 or below; and
2. Meets the prescriptive criteria for such component established
by the IECC.
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Answer
Yes, there is a tax credit for storm windows and doors in 2009 and
2010 that meet this criteria:
Storm Door.
A storm door that, in combination with the exterior door over
which it is installed--
1. (a) Has a U-factor and SHGC of 0.30 or below; and
2. (b) Meets the prescriptive criteria for such component
established by the IECC.
To verify tax credit eligibility, ask your retailer to provide the Manufacturer's
Certification Statement for the storm windows/doors you plan to
purchase.
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“Most Americans spend about 90 percent of their time
indoors, where pollutant levels may be 2-5 times
higher, and occasionally 100 times higher, than
outdoors.”
—The Environmental Protection Agency (EPA)
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2008 Titl 24
Title
Residential Lighting
Is available from the
California Lighting
Technology Center
www.CLTC.ucdavis.edu
2008 Title 24 Residential Lighting Overview 2
California 2008 Title 24 Lighting Basics Page 1
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These lighting fixtures are designed and built to operate
only energy-efficient light sources, such as
fluorescent T8 lamps, compact fluorescent lamps
(CFLs), and high intensity discharge (HID) lamps.
2008 Title 24 Residential Lighting Overview 3
A high efficacy luminaire is one that meets the
efficacies listed in Table 150-C of the Standards
(shown as Tables 6-1 and 6-2 in this presentation),
contains only high efficacy lamps or high efficacy
LED lighting, and must not contain a socket which
allows any low efficacy lighting system to be used.
For example, any luminaire containing a medium
screw base socket is classified as low efficacy,
regardless of the type of lamp installed into that
socket.
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Must not contain medium based incandescent sockets.
[
[except for Outdoor high intensity discharge lighting (
p g y g g g (HID) containing a HID
) g
lamp, and factory-installed hardwired HID ballast and HID rated socket,
and meeting minimum lumens per watt]
Medium Base Lamp 4-pin Quad Compact Medium Base HID
Fluorescent
Fluorescent
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http://www.buy-cfls.com/
http://www.schoolhouseelectric.com/
http://www schoolhouseelectric com/
http://www.destinationlighting.com/
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Select the appropriate
color:
Warmer lamp colors
(CCT = 2700-3000K)
= closest color
match to
incandescent
2008 Title 24 Residential Lighting Overview 11
Incandescent HPS
Incandescent
Cool White CFL
2008 Title 24 Residential Lighting Overview 12
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1. A gasket is attached to the bottom of the certified airtight
housing prior to the installation of the ceiling (i.e. drywall or
other ceiling materials) to create an airtight seal.
g ) g
OR
2. A gasket is applied between the certified airtight housing
and the ceiling opening after the ceiling has been installed.
OR
3. Caulk is applied between the certified airtight housing and
the ili
th ceiling after the ceiling h been i t ll d
ft th ili has b installed.
OR
4. A certified airtight trim kit is attached to the housing after
the ceiling has been installed.
Title 24 2008 Overview—Lighting 15
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Low Efficacy System Required High Efficacy System
1 recessed can with screw Minimum Required:
based socket. 100 Watts
Relamping rated wattage on Example:
factory installed label 4 CF fixtures x 26 watts
= 100 Watts = 104 watts
Low Efficacy System
= 100 Watts
2008 Title 24 Residential Lighting Overview 19
Once it has been determined that the installed low efficacy lighting
wattage is no greater than the installed high efficacy wattage, a
limited number of additional low efficacy lighting wattage may be
installed. The dditi
i t ll d Th additional l efficacy wattage shown b l i T bl
l low ffi tt g h below in Table
6-3 may be installed provided that all of the following conditions are
met:
1. All installed low efficacy luminaires in the kitchen are controlled by a
manual-on occupant sensor, dimmer, energy management control
system (EMCS), or a multi-scene programmable control system,
And
2. All permanently installed luminaires in garages, laundry rooms,
closets greater than 70 square feet, and utility rooms are high
efficacy and are also controlled by a vacancy sensor.
THEN
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2008 Title 24 Residential Lighting Overview 21
At least half the installed wattage of luminaires in
kitchens shall be high efficacy.
However, lighting installed inside a cabinet is not
included in the wattage calculation that determines
the half of the installed wattage that is high efficacy.
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Lighting internal to cabinets is not considered when
determining that at least 50% of the permanently
installed lighting in a residential kitchen is high
efficacy. Permanently installed lighting that is
internal to cabinets shall use no more than 20 watts
of power per linear foot of illuminated cabinet.
2008 Title 24 Residential Lighting Overview 23
The following lighting systems are not considered
lighting internal to cabinets:
1. Lighting recessed into a cabinet for the purpose of
illuminating surfaces outside of the cabinet
2. Lighting attached to any surface on the outside of a
cabinet, including the top, bottom, or sides
3. Lighting attached to the inside of a cabinet, such as
reflector lamps, for the purpose of projecting light
out of the cabinet.
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Question
I have 23 linear feet of upper kitchen cabinets, and 32 feet of lower
kitchen cabinets. I want to install lighting on the inside of 18 feet of
cabinets
upper cabinets which have glass doors. The upper cabinets have
three shelves. I want to install lights under all three shelves. How
many watts of lighting may I install in the cabinets?
Answer
The cabinet lighting allowance is based upon the linear foot of
illuminated cabinet, regardless of the number of shelves in each
cabinet.
cabinet
Therefore, multiply 18 feet times 20 watts per foot = 360
watts. You are allowed to install up to 360 watts of
internal cabinet lighting.
2008 Title 24 Residential Lighting Overview 25
Question
In the above example, if I have 18 linear feet of upper cabinets with
p , pp
glass doors, but I only want to install lighting in 10 linear feet of
the cabinets, how many watts of lighting may I install in the
cabinets?
Answer
The allowance is based upon the linear feet of cabinet that is
illuminated. In this case, multiply 10 feet time 20 watts per foot =
200 watts. You are allowed to install up to 200 watts of internal
cabinet lighting.
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The residential lighting Standards require luminaire
input power (wattage) to be determined in kitchens.
Blank electrical boxes §150(k)3
In residential kitchens, the wattage of electrical boxes
finished with a blank cover or where no electrical
equipment has been installed, and where the
electrical b can b used f a l i i or a
l t i l box be d for luminaire
surface mounted ceiling fan, shall be calculated as
180 watts of low efficacy lighting per electrical box.
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High efficacy lighting must be switched separately from
low efficacy lighting.
There are no longer any constraints on where the
separate switches are located.
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Lighting in areas adjacent to the kitchen, such as
dining and nook areas and even family rooms, is
considered to be kitchen lighting if it is not
separately switched from the kitchen lighting. The
switches may be mounted on the same faceplate,
but as long as the lights can be switched
independently, these areas do not count as being in
the kitchen.
Title 24 2008 Overview—Lighting 29
All hardwired lighting must be high efficacy,
Or
Controlled by a manual-on motion sensor,
(Occupancy/Vacancy Sensor)
2008 Title 24 Residential Lighting Overview 30
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48. California Center for Sustainable Energy
Lighting in Garages, Laundry Rooms, and Utility Rooms
must all meet the same requirements as Bathrooms.
Motion control wall switch
2008 Title 24 Residential Lighting Overview 31
A manual-on motion sensor must turn off automatically
when no one is present, then as normally done when
lighting is needed, must be turned on manually with
a switch.
2008 Title 24 Residential Lighting Overview 32
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50. California Center for Sustainable Energy
Question
We would like to use incandescent lighting in a bathroom
along with a vacancy sensor. Alth gh th sensor has
l g ith Although the h
the “manual-on” capability, it also has the capability of
turning the lights on automatically by flipping a switch
that is located under the switch plate cover. Does this
sensor meet the requirements of the Standards?
Answer
No, this sensor does not meet the requirements of the
Standards. Section 119 requires that the vacancy
sensor shall not have an override switch that converts
the sensor from a manual-on to an automatic-on system.
2008 Title 24 Residential Lighting Overview 35
Must be manual on.
Time Delay cannot be greater than
30 minutes.
Cannot be ‘locked’ in a permanent
‘on’ state.
2008 Title 24 Residential Lighting Overview 36
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51. California Center for Sustainable Energy
Dimmers, which are already common in many
residential applications, allow the room occupants
to lower the room lighting (and thus the power used)
as desired.
2008 Title 24 Residential Lighting Overview 37
All installed luminaires shall either be high efficacy
Or
shall be controlled by a vacancy sensor or dimmer.
2008 Title 24 Residential Lighting Overview 38
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53. California Center for Sustainable Energy
1. Controlled by a manual on/off switch, and
2. A motion sensor that is not equipped with an override or bypass
switch that di bl the motion sensor which automatically turns
i h h disables h i hi h i ll
off the lights when no motion is detected, and
3. One of the following three methods to automatically turn the lights
off during the daytime:
A. Photocontrol not having an override or bypass switch that
disables the photocontrol; or
B. Astronomical time clock not having an override or bypass switch
that disables the astronomical time clock; or
C. Energy management control system (EMCS) not having an
override or bypass switch that allows the luminaire to be always
on.
on.
Title 24 2008 Overview—Lighting 41
Lighting in detached storage buildings less than 1000
square feet, when those storage buildings are
located on a residential site, is not required to
comply with §150(k)11.
Title 24 2008 Overview—Lighting 42
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54. California Center for Sustainable Energy
When it is desirable to allow residential outdoor lighting to
be on for more than 30 minutes after the sensor has
stopped sensing activity For example when someone is
activity. example,
entertaining in their backyard, they may want the lights
to stay on longer than 30 minutes. To address this issue,
the residential lighting Standards allow low efficacy
outdoor luminaires to be controlled by a motion sensor
controlled by a temporary override switch to bypass the
motion sensing function, provided that the motion
ti i gf ti id d th t th ti
sensor is automatically reactivated within six hours. The
motion sensor must automatically reactivate itself
without any action on part of the operator.
Title 24 2008 Overview—Lighting 43
Lighting that is not permanently attached to buildings,
such as decorative landscape lighting when it is not
permanently attached to buildings, is not regulated
by the Standards.
Title 24 2008 Overview—Lighting 44
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55. California Center for Sustainable Energy
Parking lots and carports for a total of seven or fewer
cars per site must meet the residential outdoor
lighting requirements as applicable.
<7 Cars per site
p
Title 24 2008 Overview—Lighting 45
Parking lots and carports for a total of eight or more
cars per site must meet the nonresidential outdoor
lighting requirements (see §130, §132, §134, and
§147).
Parking garages that house eight or more cars shall
meet the interior lighting control and power
requirements of the Nonresidential Standards
Standards.
≥8 Cars per site
Title 24 2008 Overview—Lighting 46
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56. California Center for Sustainable Energy
The nonresidential outdoor lighting Standards include
the following requirements for parking lots and car
ports that accommodate a total of eight or more
vehicles per site:
Luminaires rated for lamps over 100W must have a
lamp efficacy of at least 60 lumens per watt, or be
controlled by a motion sensor Luminaires rated for
sensor.
use only with LED, compact fluorescent, linear
fluorescent, metal halide, and high pressure sodium
lamps are not affected by this requirement.
Title 24 2008 Overview—Lighting 47
Luminaires with lamps rated over 175 watts shall be
designated “cutoff” in a photometric test report.
Luminaires shall be controlled by a photocontrol, or an
astronomical time switch that turns the lighting off
when daylight is available.
Title 24 2008 Overview—Lighting 48
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57. California Center for Sustainable Energy
Question
I have a low-rise multi-family complex with a total of 20
parking spaces. H
ki g However, th parking spaces are
the ki g
arranged throughout the site in groups of only 4 spaces
each. Are these parking spaces required to comply with
the nonresidential outdoor lighting requirements?
Answer
Yes, these spaces are required to comply with the
nonresidential outdoor lighting Standards. Parking lots
and carports for a total of eight or more cars per site
must meet the nonresidential outdoor lighting
requirements.
Title 24 2008 Overview—Lighting 49
Lighting for common areas of low-rise residential
buildings with four or more dwelling units shall be
high efficacy, or shall be controlled by an occupant
sensor. Occupant sensors used in common areas
may have the capability of turning the lights on
automatically.
Title 24 2008 Overview—Lighting 50
California 2008 Title 24 Lighting Basics Page 25
58. California Center for Sustainable Energy
2008 Title 24 Residential Lighting Overview 51
Other Issues
2008 Title 24 Residential Lighting Overview Page 52
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59. California Center for Sustainable Energy
§130(b) and (c)
The design and installation of all lighting systems
systems,
lighting controls and equipment in high-rise
residential dwelling units and in hotel/motel guest
rooms shall comply with the applicable provisions of
§150(k).
Title 24 2008 Overview—Lighting 53
Permanently installed luminaires include the following:
1. Lighting attached to walls, ceilings, columns
2. Track d flexible lighting
2 T k and fl ibl li hti systems t
3. Lighting inside permanently installed cabinets
4. Lighting attached to the top or bottom of permanently installed
cabinets
5. Lighting attached to ceiling fans
6. Lighting integral to exhaust fans.
7. Lighting that is integral to garage door openers if it is designed to be
used as general lighting, is switched independently from the garage
door opener, and does not automatically turn off after a pre-
determined amount of time.
Title 24 2008 Overview—Lighting 54
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60. California Center for Sustainable Energy
Permanently installed lighting does not include
1. Portable lighting as defined by §101
2. Lighting installed by the manufacturer in refrigerators, stoves,
microwave ovens, exhaust hoods for cooking equipment,
refrigerated cases, vending machines, food preparation
equipment, and scientific and industrial equipment.
3. Lighting in garage door openers which consists of no more
than two screw-based sockets integrated into the garage
screw-
door opener by the manufacturer, where the lights
automatically turn on when the garage door is activated, and
automatically turn off after a pre-determined amount of time.
Title 24 2008 Overview—Lighting 55
LED—Light Emitting Diode Lighting
2008 Title 24 Residential Lighting Overview Page 56
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61. California Center for Sustainable Energy
The 2008 Standards include the following language to
address the use of LED lighting:
1. §101 contains definitions for LED lighting.
2. §119 requires LED lighting to be certified to the
Energy Commission before it can be classified as
high efficacy for residential applications. An LED
luminaire,
l i i or LED light engine with integral heat sink,
li ht i ith i t lh t i k
shall be classified as low efficacy if it has not been
certified to the Energy Commission as high efficacy.
Title 24 2008 Overview—Lighting 57
3. §130(d)5 points to Reference Joint Appendix JA-8 for
determining how much power (wattage) is installed
with an LED lighting system. JA-8 requires that
JA-
wattage for LEDs shall be the maximum rated input
wattage of the LED lighting system, including power
used by fans, transformers, and power supply
devices.
4. §150(k)1 and Table 150-C (shown as Table 6-2) has
requirements for determining when an LED lighting
source system can be classified as high efficacy.
Title 24 2008 Overview—Lighting 58
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62. California Center for Sustainable Energy
Lighting controls, ballasts for residential recessed
luminaires, and high efficacy LED lighting source
systems shall not be installed unless they have been
certified by the manufacturer and listed on this
database. The database and certification
instructions are available from the following web
link:
http://www.energy.ca.gov/appliances/appliance/index.html
Title 24 2008 Overview—Lighting 59
Controls
2008 Title 24 Residential Lighting Overview Page 60
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Following are controls that are required for compliance with the 2008
residential lighting Standards:
All Permanently Installed Luminaires must be switched separately from
low efficacy luminaires.
Exhaust Fans. There are two options for the switching of lighting
associated with exhaust fans:
1. All lighting must be switched separately from exhaust fans,
OR
2. For an exhaust fan with an integral lighting system, the lighting
system must be able to be manually turned on and off while
allowing the fan to continue to operate for an extended period of
time. An exhaust fan may need to run continuously if used to
comply with §150(o), (Whole house Ventilation).
150(o),
Title 24 2008 Overview—Lighting 61
All permanently installed luminaires shall be switched
with readily accessible controls that permit the
luminaires to be manually switched on and off.
All lighting controls and equipment shall be installed in
accordance with the manufacturer's instructions.
Title 24 2008 Overview—Lighting 62
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64. California Center for Sustainable Energy
Multiple Switches. This requirement applies to all three-
way, four-way, and other lighting circuits controlled by
more than one switch.
1. No controls shall bypass the dimmer or vacancy
sensor function.
2. The dimmer or vacancy sensor shall be certified to
the E
th Energy Commission th t it complies with the
C i i that li ith th
applicable requirements of §119.
Title 24 2008 Overview—Lighting 63
For control systems consisting of two or more
components, such as an Energy Management
Control System (EMCS), the manufacturer of the
control system shall certify each of the components
required for the system to comply with §119.
Title 24 2008 Overview—Lighting 64
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65. California Center for Sustainable Energy
The Standards do not require a vacancy sensor to be
used with any high efficacy luminaire.
Manual-on / automatic-off occupant sensors, also
known as vacancy sensors, automatically turn lights
off if an occupant forgets to turn them off when a
room is unoccupied. Additionally, these sensors shall
provide the occupant with the ability to turn the
lights off manually upon leaving the room, and turn
them on manually upon entering the room.
Title 24 2008 Overview—Lighting 65
Vacancy sensors are required to be certified as meeting all
of the following requirements:
Provides the
P id th occupant with the ability to manually turn the
t ith th bilit t ll t th
lights on and off.
Shall be capable of turning off the lighting automatically
within 30 minutes or less after the room has been
vacated in response to the absence of occupants in the
room, and
Have a visible status signal that indicates that the device is
operating properly or that it has failed or malfunctioned.
The visible status signal may have an override switch
that turns the signal off.
Title 24 2008 Overview—Lighting 66
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66. California Center for Sustainable Energy
Shall not turn on the lighting automatically, except the
sensor shall have a grace period of 15 seconds to
30 seconds to turn on the lighting automatically
after the sensor has timed out, and
Shall not have an override switch that disables the
vacancy sensor, and
Shall t have an override switch that converts the
Sh ll not h id it h th t t th
sensor from a manual-on to an automatic-on system.
manual- automatic- system
Title 24 2008 Overview—Lighting 67
Dimmers are required to be certified to the Energy Commission
as meeting all of the following requirements:
1.
1 Be capable of reducing power consumption by a minimum of
65 percent when the dimmer is at its lowest light level, and
2. If the device is a dimmer controlling incandescent or
fluorescent lamps, provide electrical outputs to lamps for
reduced flicker operation through the dimming range, so that
the light output has an amplitude modulation of less than 30
percent for frequencies less than 200 Hz, and without
causing premature l
i lamp failure; and
f il d
3. Be listed by a rating lab recognized by the International Code
Council (ICC) as being in compliance with Underwriters
Laboratories Standards, and
Title 24 2008 Overview—Lighting 68
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67. California Center for Sustainable Energy
4. If the device is a wall box dimmer designed to be used in
a three or more-way circuit with non-dimmable switches,
the level set by the dimmer shall not be overridden by
dimmer,
any of the switches in the circuit. The dimmer and all of
the switches in the circuit shall have the capability of
turning lighting OFF if it is ON, and turning lighting ON to
the level set by the dimmer if the lighting is OFF. Any wall
box dimmer that is connected to a system with an
emergency override function shall b controlled by the
g id f ti h ll be t ll d b th
emergency override.
5. If the device is a stepped dimmer, shall include an off
position to turn lights completely off.
Title 24 2008 Overview—Lighting 69
Question
I am doing minor renovations to my kitchen that has six
recessed incandescent cans and I am adding a new
luminaire over the sink. Does this luminaire have to
be a high efficacy luminaire?
Answer
Yes, all new luminaires must be high efficacy until at
least 50% of the total lighting wattage comes from
high efficacy luminaires (§152 (b) 1 and §152 (b) 2).
Title 24 2008 Overview—Lighting 70
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68. California Center for Sustainable Energy
EnergyStar CFL Information
2008 Title 24 Residential Lighting Overview Page 71
How Much Light?
"Warm light 60" means that this CFL provides the same light as a 60-watt
60-
incandescent bulb.
"Warm" indicates a color temperature between 2700-3000K.
2700-
Brightness is a description of light output, which is measured in lumens
(not watts).
Light bulb manufacturers include this information and the equivalent wattage
right on the packaging.
To save energy, find the bulbs with the light output you need, and then choose
the one with the lowest wattage. You can also look for a CFL that is labeled
as equivalent to the i
i l h incandescent b lb you are replacing.
d bulb l i
The color of light may also affect how bright a light appears, even if the lumens
are the same. Since most people are used to the soft yellowish glow from
incandescent light bulbs, CFLs that produce light closer to the color of
daylight (color temperatures above 3000K) may appear brighter because
the color of the light is less yellow.
yellow.
Title 24 2008 Overview—Lighting 72
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69. California Center for Sustainable Energy
Incandescent ENERGY STAR
Bulbs Qualified Light Bulbs
Watts lumens Watts
40 450 9 to 13
60 800 13 to 15
75 1,100
1 100 18 to 25
100 1,600 23 to 30
150 2,600 30 to 52
Title 24 2008 Overview—Lighting 73
Choosing the right color:
Light color is measured on a temperature scale referred to
as Kelvin (K).
Lower Kelvin numbers mean the light appears more yellow;
higher Kelvin numbers mean the light is whiter or bluer.
Most ENERGY STAR qualified bulbs are made to match the
color of incandescent bulbs at 2700 3000K
2700-3000K.
For a whiter light, look for bulbs marked 3500-4100K.
For bluer white light, look for bulbs marked 5000-6500K.
Title 24 2008 Overview—Lighting 74
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70. California Center for Sustainable Energy
Title 24 2008 Overview—Lighting 75
Use about one-quarter of the energy to produce the same
amount of light,
Last about 10 times longer,
Produce about 75 percent less heat, which reduces cooling
costs,
Save about $30 or more in electricity costs over the lifetime
of the bulb,
Have manufacturer-backed warranties, and
Meet strict energy efficiency and performance
requirements.
Title 24 2008 Overview—Lighting 76
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71. California Center for Sustainable Energy
Do the twist. Screw in your CFL by holding the
ballast (the white plastic part), NOT the
glass tubing.
Don’t flip too fast. You’ll maximize the lifetime
savings and effectiveness of your CFLs by
keeping them on for 15 minutes or more at
a time
time.
Choose 3 for 3. Only use bulbs labeled as
three-way on three-way sockets.
Title 24 2008 Overview—Lighting 77
Don’t dim a non-dimmable. Only use bulbs labeled as
dimmable on dimmer switches.
Check your controls. Most photocells, motion sensors and
electric timers are not designed to work with CFLs. Always
check with the manufacturer of the control for
compatibility.
Give them air. CFLs are sensitive to extreme temperatures, so
place your CFLs in open fixtures indoors. Using them in
enclosed fixtures indoors can create a hot environment
that reduces the lifetime of your bulbs. Note that covered
reflectors are best used in recessed cans
cans.
Protect them outside. Protect bulbs from the elements by
placing them inside enclosed fixtures outdoors. For colder
climates, look at the packaging for optimal operating
temperatures.
Title 24 2008 Overview—Lighting 78
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2008 Title 24 Residential Lighting Overview Page 79
California 2008 Title 24 Lighting Basics Page 40
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I d Ai Q lit d
Indoor Air Quality and
Mechanical Ventilation
2008 Title 24 Ventilation Basics
Indoor Air Quality and
Mechanical Ventilation—§150(o) and 152(a)
With the 2008 update, all low-rise residential buildings
low-
are required to have a whole house ventilation
system and satisfy other requirements to achieve
acceptable indoor air quality. The CEC adopted the
requirements of ASHRAE Standard 62.2-2007,
62.2-
except that opening and closing windows (although
permitted by ASHRAE) is not an acceptable option in
California.
2008 Title 24 Ventilation Basics Page 2
Indoor Air Quality and Mechanical Ventilation Page 1
74. California Center for Sustainable Energy
Ventilation for Indoor Air Quality
§150(o)
All dwelling units shall meet the requirements
of ANSI/ASHRAE Standard 62.2. Window
62 2
operation is not a permissible method of
providing the Whole Building Ventilation
required in Section 4 of that Standard.
2008 Title 24 Ventilation Basics Page 3
Ventilation for Indoor Air Quality
—CONTINUED
The indoor air quality requirements are not
triggered for renovations
renovations.
2008 Title 24 Ventilation Basics Page 4
Indoor Air Quality and Mechanical Ventilation Page 2
75. California Center for Sustainable Energy
Ventilation for Indoor Air Quality
—CONTINUED
The typical solutions are described in the following
section.
Kitchens and bathrooms shall have local exhaust
systems vented to the outdoors.
Clothes dryers shall be vented to the outdoors.
Ventilation air shall come from the out of doors and
shall not be transferred from adjacent dwelling units,
garages or crawlspaces.
2008 Title 24 Ventilation Basics Page 5
Ventilation for Indoor Air Quality
—CONTINUED
Ventilation system controls shall be labeled and the home
owner shall be provided with instructions on how to operate
the system.
h
Combustion appliances shall be properly
vented and air systems shall be
designed to prevent back drafting.
The wall and openings between the house and the garage shall
b sealed.
be sealed.
l d
Habitable rooms shall have windows with a ventilation area of at
least 4% of the floor area (see 3.5.2).
2008 Title 24 Ventilation Basics Page 6
Indoor Air Quality and Mechanical Ventilation Page 3
76. California Center for Sustainable Energy
Ventilation for Indoor Air Quality
—CONTINUED
Mechanical systems including heating and air conditioning
systems that supply air to habitable spaces shall have MERV 6
filt
filters or b tt
better.
Air inlets (not exhaust) shall be located away from known
contaminants.
Air moving equipment used for to meet either the whole building
ventilation requirement or the local exhaust requirement shall
be rated in terms of air flow and sound Continuously operating
sound.
fans shall be less than 1.0 sone, and intermittently operated
sone,
fans shall be less than 3.0 sone. Remotely located equipment
sone.
is excepted.
2008 Title 24 Ventilation Basics Page 7
Typical Solutions for Whole Building
Ventilation
There are three generic solutions to meeting the
outside air ventilation requirement:
q
Exhaust ventilation,
Supply ventilation, or a
Combination of supply and exhaust ventilation. If
the supply and exhaust flows are within 10% of
each other this is called a balanced ventilation
system.
2008 Title 24 Ventilation Basics Page 8
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77. California Center for Sustainable Energy
Exhaust Ventilation
Exhaust Ventilation is usually achieved by a quiet ceiling-
ceiling-
mounted bath fan or remote mounted inline or exterior-
exterior-
mounted f
d fans.
Air is drawn from the house by the exhaust fan and outdoor air enters
the house through leaks in the building envelope. Because the
leaks are generally uniformly scattered throughout the house,
outdoor air entering the house
does not generally create
drafty or uncomfortable
conditions.
2008 Title 24 Ventilation Basics Page 9
Many high quality bath fans are available in the 30 to 150
cfm size range and are quiet enough to be used
continuously. One or more fans of this size will meet the
requirements of most homes.
The exhaust fan can be a dedicated IAQ fan or it can be a
more typical bath fan that is used for both whole
building ventilation and local ventilation.
2008 Title 24 Ventilation Basics Page 10
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78. California Center for Sustainable Energy
Supply Ventilation
Supply ventilation works in just the opposite way as
exhaust ventilation. Outside air enters the house
through a dedicated supply fan or through the
central HVAC system air handler. The fan(s)
pressurizes the house and air escapes through leaks
in the building envelope.
2008 Title 24 Ventilation Basics Page 11
Central Fan-Integrated Ventilation
System
Central Fan-Integrated Ventilation System is a central forced air
Fan-
heating and/or cooling system which is intended to operate on a
regular basis to bring in outdoor ventilation air and/or distribute air
around the home for comfort and ventilation even when heating
and cooling are not needed.
This strategy, uses the
negative pressure in the
return plenum to pull in
outdoor air and th push it
td i d then h
through the air handler.
2008 Title 24 Ventilation Basics Page 12
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79. California Center for Sustainable Energy
Combination Ventilation
Combination systems use both exhaust fans and
supply fans. If both fans supply the same air flow
pp y pp y
the system is balanced and the house has a
neutral pressure, as opposed to a supply
ventilation system which results in a positive
pressure or an exhaust ventilation system which
results in a negative pressure
pressure.
2008 Title 24 Ventilation Basics Page 13
Combination Ventilation—CONTINUED
Combination systems are often integrated devices,
sometimes with a heat exchanger or heat recovery
g y
wheel, the supply and exhaust airstreams are typically
of equal flow. Combination systems can also consist of a
mixture of supply fans and exhaust fans.
2008 Title 24 Ventilation Basics Page 14
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80. California Center for Sustainable Energy
Ventilation Flow Rate
(Chapter 4 of ASHRAE 62.2)
The continuous ventilation rate is one cubic foot per minute
(cfm) for each 100 ft2 of floor area plus 7.5 cfm for each
occupant. The number of occupants is approximated as
the number of bedrooms plus one.
Equation 4-1
4-
Ventilation Rate (cfm) = CFA/100 + [7.5 x (Number Bedrooms +1)]
Table 4-7 may be used to determine the required
4-
ventilation.
2008 Title 24 Ventilation Basics Page 15
Table 4-7 Continuous Ventilation
Rate
2008 Title 24 Ventilation Basics Page 16
Indoor Air Quality and Mechanical Ventilation Page 8
81. California Center for Sustainable Energy
Example 4-6–Required Ventilation
Question
What is the required continuous ventilation rate required
for a 3 bedroom, 1,800 ft2 townhouse.
Answer
48 cfm.
This is calculated as:
1800/100 + (3+1)*7.5 = 48 cfm.
Using Table 4-7, the required ventilation rate would be 60 cfm.
4-
2008 Title 24 Ventilation Basics Page 17
Example 4-6 – Required Ventilation
—CONTINUED
Question
The house I am building has a floor area of 2,240 ft2 and 3
2 240
bedrooms. My calculations come out to 52.4 cfm. Can I
use a 50 cfm fan?
Answer
No, a 50 cfm fan does not meet the standard. You would
No,
need to select the next larger size fan, such as a unit
rated at 55 cfm or 60 cfm. If you use Table 4-7 to select
4-
the fan size, you get 60 cfm.
2008 Title 24 Ventilation Basics Page 18
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82. California Center for Sustainable Energy
Ventilation Rate for Combination
Systems
When a combination ventilation system is used,
meaning that both supply and exhaust fans are
installed, the provided ventilation rate is the larger of
the total supply airflow or the total exhaust airflow.
The airflow rates of the supply and exhaust fans
cannot be added together.
2008 Title 24 Ventilation Basics Page 19
Intermittent Ventilation
In some cases, it may be desirable to design a
ventilation system that operates intermittently. The
most common example of intermittent ventilation is
a when outside air is ducted to the return plenum
and the central HVAC fan is used to provide
ventilation.
This type of ventilation is permitted as long as the
ventilation air flow is increased to respond to the
fewer hours of fan operation. The increased flow
depends on the fraction of time the fans operate.
2008 Title 24 Ventilation Basics Page 20
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83. California Center for Sustainable Energy
Intermittent Ventilation
—CONTINUED
Figure 4-23 shows the multiplier based on the total
4-
hours per day of fan operation. There is very little
need to increase fan flow when the fans operate for
more than about 20 hours per day. However, the
required flow rate can be 10 to 20 times greater
when the fans operate for less than 6 hours per day.
2008 Title 24 Ventilation Basics Page 21
Equation 4-2
The multipliers in Figure 4-23 are determined from the
4-
following equation, which can be used in lieu of the
graph.
Qf = Qr/(ef)
Qr/(ef)
Where:
Qf = fan flow rate
Qr = ventilation air requirement (continuous)
e = ventilation effectiveness, (Table 4-8, next slide)
4-
f = fractional on-time.
on-
2008 Title 24 Ventilation Basics Page 22
Indoor Air Quality and Mechanical Ventilation Page 11