Download - New Title 24 Standards For Lighting Windows And Ventilation

Lighting, Windows & Ventilation

California Title 24 Standards

Prepared by Douglas Beaman Associates

Windows, Lighting & Ventilation California Title 24 Standards

Table of Contents

1 Introduction and Window Basics

2 Lighting Basics

3 Indoor Air Quality and Mechanical Ventilation

Copyright 2009 Douglas Beaman Associates ©

Wi d Li hti d Windows, Lighting and Ventilation

Welcome and Window Basics

Page 2Welcome and Window Basics

California Center for Sustainable Energy

Introduction and Window Basics Page 1

Presenters:

Douglas Beaman,

Gary Wollin

608 - 13th Street

Modesto, California 95354

[email protected]

[email protected]

(209) 524-1000


January 1, 2010

Any building permit applied for on or after January 1 Any building permit applied for on or after January 1, 2010 must comply with the new Standards.




Available in PDF format from the CEC website:

Publication #:CEC-400-2008-001-CMF

The Standards contain the actual code language, harder to understand harder to understand, but the last word.

www.energy.ca.gov/title-24


Available in PDF format from the CEC website:from the CEC website:

Publication #:CEC-400-2008-016-CMF

Designed to be used by building departments, builders energy builders, energy consultants.

www.energy.ca.gov/title24Page 6Welcome and Window Basics



Welcome and Window Basics Page 7

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,

l or people.




Almost no homes enjoyed the benefits of insulation. Homes either had mass,

ll d l i b stone walls, sod or logs, were timber 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 expensive and many homes had double shutters.

Homes were naturally ventilated. Summer and Winter.


Homes for millennia had heating that was provided by a fireplace.

I f t th E gli h d f i d d t f In fact the English word for window does not come from a 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 = eyeOld Norse vindauga, equiv. to vindr wind + auga eye




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 sheetsinto 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.


The crown process was a later technique, in which a gather of glass was blown and shaped into a flattened globe or crown. Th il d h d h fl id h bl i The pontil rod was attached to the flat side, the blowpipe 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.




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.


Today, nearly all window glass is made mechanically by drawing glass upward from a molten pool fed y g g p pfrom 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.




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 ofinsulation value have been nanogel-filled windows, but those are just translucent, and do not allow clear vision through the glass.


U-Factor

SHGC—(Solar Heat Gain Coeffieicnt)SHGC (Solar Heat Gain Coeffieicnt)

AL—(Air Leakage)

VT—Visible Light Transmittance




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).


The fraction of solar radiation transmitted through a window, expressed as a percentage. The lower a window’s SHGC the less solar heat it transmits 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.




Heat loss and gain occur by infiltration through cracks in the window assembly. It is indicated by y yan 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 At this time the AL is optionalassembly. At this time, the AL is optional.

Select windows with an AL of 0.30 or less (units are cfm/sq ft).


The visible transmittance (VT) is an optical property that indicates the amount of visible light transmitted The NFRC's VT is a whole window 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 d i bl t i i d light desirable to maximize daylight.




Welcome and Window Basics 21

An Insulating Glass Unit is the transparent component of a window or door assembly. An IGU p ycomprises 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 fillgas-fill.




Single-Glazed with Clear GlassRelative to all other glazing 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 gconditions) while permitting the highest daylight transmission.


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" desired, for example, 1/4 inch (6 mm). The optimum gap width for krypton is 3/8 (9mm).

A mixture of krypton and argon gases is also used as a compromise between thermal performance and cost.




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 surface primarily to reduce the U factor by suppressing radiative heat 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.


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.




Back to California


§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.





Window values:

U-factors from 0.55 – 0.67 to 0.40




§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.


Type 1

Manufactured products are delivered pre-assembled Manufactured products are delivered pre assembled from the factory.

This is the most common type of fenestration in residential construction.




Type 2

Site-built products are glazed or assembled on site 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 Directoryfrom NFRC s Certified Products Directory.

See http://www.NFRC.org.


Type 3

Field-fabricated products are built on site using 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 SHGCTable 116 B for SHGC.





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 glass blocks are yp ginstalled.

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.

f S GCFor this example, the glass block is operable and clear, therefore the SHGC is 0.70.

Glass block is considered a field-fabricated product and therefore does not need a label.




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).


The NFRC label if one is available, orThe 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.




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?need to comply with the Standards?


Method 1

Use the default U-factor from Standards Table 116-AUse the default U-factor from Standards Table 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 ofglazing 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.)




Method 2

Determine the U-factor from the Reference Determine the U factor from the Reference 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.”


Method 3

If the skylight has been tested and certified pursuant to 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.




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?


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 or the Package D value for performance compliance (Exception to §151(f)3A).




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.





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 t l b l i di ti g U f t SHGC d i temporary label indicating U-factor, SHGC, and air infiltration rate (only field-fabricated products are exempt from labeling requirements).





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 openingapplied to the area of the rough opening.


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.




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 openingapplied to the area of the rough opening.


Advisory: New Year, New Numbers

As of January 4, 2010, ENERGY STAR qualified windows, doors, and skylights will meet new performance levels skylights will meet new performance 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 currentlyqualify 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.




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.


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.




“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)





2008 Titl 242008 Title 24Residential 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

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.


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.




Must not contain medium based incandescent sockets.[except for Outdoor high intensity discharge lighting (HID) containing a HID [ p g y g g g ( ) g

lamp, and factory-installed hardwired HID ballast and HID rated socket, and meeting minimum lumens per watt]


Medium Base LampMedium Base Lamp Medium Base HIDMedium Base HID44--pin pin Quad CompactQuad CompactFluorescenFluorescentt




http://www.buy-cfls.com/

http://www schoolhouseelectric com/http://www.schoolhouseelectric.com/

http://www.destinationlighting.com/





Select the appropriate color:

Warmer lamp colors

(CCT = 2700-3000K) = closest color match to incandescent


HPSIncandescent

Incandescent

2008 Title 24 Residential Lighting Overview

CFL12

Cool White



Must be approved for zero-clearance insulation cover (IC)

AndAndElectronic Ballast

And

Air-tight (AT)


© Progress Lighting, used by permission

For these reasons, luminaires recessed in insulated ceilings must meet three requirements:

They must be approved for zero clearance insulation cover (IC) They must be approved for zero clearance insulation cover (IC) by Underwriters Laboratories or other testing/rating laboratories recognized by the International Conference of Building Officials. This enables insulation to be packed in direct contact with the luminaire.

The luminaire must have a label certifying air tight (AT) construction. Air tight construction means that leakage h h h l i i ill d 2 0 f h d through the luminaire will not exceed 2.0 cfm when exposed

to a 75 Pa pressure difference, when tested in accordance with ASTM E283.

The luminaire must be sealed with a gasket or caulk between the housing and ceiling.




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

OROR2. A gasket is applied between the certified airtight housing

and the ceiling opening after the ceiling has been installed.OROR3. Caulk is applied between the certified airtight housing and

th ili ft th ili h b i t ll dthe ceiling after the ceiling has been installed.OROR4. A certified airtight trim kit is attached to the housing after

the ceiling has been installed.

Title 24 2008 Overview—Lighting 15




Luminaires recessed in insulated ceilings must be IC rated and have a gasket or caulking between the housing and ceiling to prevent the flow of heated or cooled air between conditioned and unconditioned spaces. The luminaire must include a label certifying airtight or similar designation to show air leakage less than 2.0 CFM at 75 Pascals when tested in accordance with ASTM E283. The label must be clearly visible for the building inspector.






Low Efficacy System Required High Efficacy System

1 recessed can with screw based socket.Relamping rated wattage on factory installed label

= 100 WattsLow Efficacy System

Minimum Required:100 WattsExample:4 CF fixtures x 26 watts

= 104 wattsLow Efficacy System

= 100 Watts


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 i t ll d Th dditi l l ffi tt g h b l i T bl installed. The additional low efficacy wattage shown 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





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.




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.


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.




QuestionI 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 kitchen cabinets. I want to install lighting on the inside of 18 feet of upper cabinets which have glass doors. The upper cabinets have three shelves. I want to install lights under all three shelves. How How many watts of lighting may I install in the cabinets?many watts of lighting may I install in the cabinets?

AnswerThe cabinet lighting allowance is based upon the linear foot of

illuminated cabinet, regardless of the number of shelves in each cabinetcabinet.

Therefore, multiply 18 feet times 20 watts per foot = 360 watts. You are allowed to install up to 360 watts of internal cabinet lighting.


Question

In the above example, if I have 18 linear feet of upper cabinets with p , ppglass 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.




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

l t i l b b d f l i i electrical box can be used for a luminaire or a surface mounted ceiling fan, shall be calculated as 180 watts of low efficacy lighting per electrical box.


High efficacy lighting must be switched separately from low efficacy lighting.

There are no longer any constraints on where the separate switches are located.




Lighting in areas adjacent to the kitchen, such as Lighting in areas adjacent to the kitchen, such as dining and nook areas and even family rooms, is dining and nook areas and even family rooms, is considered to be kitchen lighting if it is not considered to be kitchen lighting if it is not separately switched from the kitchen lighting. 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.


All hardwired lighting must be high efficacy,

OrOr

Controlled by a manual-on motion sensor, (Occupancy/Vacancy Sensor)




Lighting in Garages, Laundry Rooms, and Utility Rooms must all meet the same requirements as Bathrooms.


Motion control wall switch

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.




All luminaires shall either be high efficacy

Or

Controlled by a manual-on motion sensor, (Occupancy/Vacancy Sensor)

Closets that are less than 70 square feet are exempt from this requirements.


Bathroom is a room containing a shower, tub, toilet or a sink that is used for personal hygiene.





QuestionWe would like to use incandescent lighting in a bathroom

l g ith Alth gh th h along with a vacancy sensor. Although the sensor has 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?

AnswerNo, 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.


Must be manual on.

Time Delay cannot be greater than Time Delay cannot be greater than 30 minutes.

Cannot be ‘locked’ in a permanent ‘on’ state.




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.


All installed luminaires shall either be high efficacy

OrOr

shall be controlled by a vacancy sensor or dimmer.




Closets less than 70 square feet are exempt from this requirement


Luminaires providing outdoor lighting, including outdoor lighting for private patios on low-rise residential b ildi i h f d lli i buildings with four or more dwelling units, entrances, balconies, and porches, and which are permanently mounted to a residential building or to other buildings on the same lot shall be high efficacy luminaires, ororthey may be low efficacy they may be low efficacy luminaires if they are controlledby all three all three of the followinglighting controls:





1.1. Controlled Controlled by a by a manual on/off switch, andand2. 2. A motion sensor that is not equipped with an override or bypass that is not equipped with an override or bypass

i h h di bl h i hi h i ll i h h di bl h i hi h i ll switch that disables the motion sensor which automatically turns switch that disables the motion sensor which automatically turns off the lights when no motion is detected,off the lights when no motion is detected, andand

3. 3. One of the following three methods to automatically turn the lights to automatically turn the lights off during the daytime:off during the daytime:A. Photocontrol not having an override or bypass switch that not having an override or bypass switch that disables the photocontrol;disables the photocontrol; ororB. Astronomical time clock not having an override or bypass switch not having an override or bypass switch that disables the astronomical time clock; that disables the astronomical time clock; or or C. Energy management control system (EMCS) not having an (EMCS) not having an override or bypass switch that allows the luminaire to be always override or bypass switch that allows the luminaire to be always onon..


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.




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 stopped sensing activity. For example, when someone is entertaining in their backyard, entertaining in their backyard, they may want the lights to stay on longer than 30 minutes. stay on longer than 30 minutes. To address this issue, the residential lighting Standards allow low efficacy Standards allow low efficacy outdoor luminaires to be controlled by a motion sensor outdoor luminaires to be controlled by a motion sensor controlled by a temporary override switch to bypass the controlled by a temporary override switch to bypass the

ti i g f ti ti i g f ti id d th t th ti motion sensing function, motion sensing function, provided that the motion sensor is automatically reactivated within six hours. The The motion sensor must automatically reactivate itself motion sensor must automatically reactivate itself without any action on part of the operator.without any action on part of the operator.


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.




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 sitep


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 Standardsrequirements of the Nonresidential Standards.

≥8 Cars per siteTitle 24 2008 Overview—Lighting 46



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 controlled by a motion sensor. Luminaires rated for use only with LED, compact fluorescent, linear LED, compact fluorescent, linear fluorescent, metal halide, and high pressure sodium fluorescent, metal halide, and high pressure sodium lamps are not affected by this requirement.lamps are not affected by this requirement.


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.




QuestionI have a low-rise multi-family complex with a total of 20

ki g H th ki g parking spaces. However, the parking spaces are arranged throughout the site in groups of only 4 spaces each. Are these parking spaces required to comply with Are these parking spaces required to comply with the nonresidential outdoor lighting requirements?the nonresidential outdoor lighting requirements?

AnswerYes, 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.


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.





Other Issues

2008 Title 24 Residential Lighting Overview Page 52



§130(b) and (c)

The design and installation of all lighting systems The design and installation of all lighting 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).


Permanently installed luminaires include the following:

1. Lighting attached to walls, ceilings, columns1. Lighting attached to walls, ceilings, columns

2 T k d fl ibl li hti t2 T k d fl ibl li hti t2. Track and flexible lighting systems2. Track and flexible lighting systems

3. Lighting inside permanently installed cabinets3. Lighting inside permanently installed cabinets

4. Lighting attached to the top or bottom of permanently installed 4. Lighting attached to the top or bottom of permanently installed cabinetscabinets

5. Lighting attached to ceiling fans5. Lighting attached to ceiling fans

6. Lighting integral to exhaust fans.6. Lighting integral to exhaust fans.

7. Lighting that is integral to garage door openers 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.




Permanently installed lighting does not include

1. Portable lighting as defined by 1. Portable lighting as defined by §§101101

2. Lighting installed by the manufacturer 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 3. Lighting in garage door openers which consists of no more than two screwthan two screw--based sockets integrated into the garage based sockets integrated into the garage door opener by the manufacturer, 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.


LED—Light Emitting Diode Lighting




The 2008 Standards include the following language to address the use of LED lighting:

1. 1. §101 contains definitions for LED lighting.

2. 2. §§119 requires LED lighting to be certified 119 requires LED lighting to be certified to the Energy Commission before it can be classified as high efficacy for residential applications. An LED l i i LED li ht i ith i t l h t i k luminaire, or LED light engine with integral heat sink, shall be classified as low efficacy if it has not been certified to the Energy Commission as high efficacy.


3. 3. §130(d)5 points to Reference Joint Appendix JA-8 for determining how much power (wattage) is installed with an LED lighting system. JAJA--8 requires that 8 requires that wattage for LEDs shall be the maximum rated input wattage for LEDs shall be the maximum rated input wattage of the LED lighting system, including power wattage of the LED lighting system, including power used by fans, transformers, and power supply used by fans, transformers, and power supply devices.devices.

4. §150(k)1 and Table 150-C (shown as Table 6-2) has requirements for determining when an LED lighting when an LED lighting source system can be classified as high efficacy.source system can be classified as high efficacy.




Lighting Lighting controls, ballasts for residential recessed controls, ballasts for residential recessed luminaires, and high efficacy LED lighting 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.htmlhttp://www.energy.ca.gov/appliances/appliance/index.html


Controls




Following are controls that are required for compliance with the 2008 residential lighting Standards:

All Permanently Installed Luminaires must be switched separately from 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 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 An exhaust fan may need to run continuously if used to comply with comply with §§150(o150(o), (Whole house Ventilation).), (Whole house Ventilation).


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.




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 1. No controls shall bypass the dimmer or vacancy sensor function.sensor function.

2. The dimmer or vacancy sensor shall be certified to 2. The dimmer or vacancy sensor shall be certified to th E C i i th E C i i th t it li ith th the Energy Commission the Energy Commission that it complies with the applicable requirements of §119.


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.




The Standards do not require a vacancy sensor to be The Standards do not require a vacancy sensor to be used with any high efficacy luminaire.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 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.


Vacancy sensors are required to be certified as meeting all of the following requirements:

P id th t ith th bilit t ll t th Provides the occupant with the ability to manually turn the 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.




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

Sh ll Sh ll t h id it h th t t th t h id it h th t t th Shall Shall not have an override switch that converts the not have an override switch that converts the sensor from a manualsensor from a manual--on to an automaticon to an automatic--on systemon system.


Dimmers are required to be certified to the Energy Commission as meeting all of the following requirements:

1 Be capable of reducing power consumption by a minimum of Be capable of reducing power consumption by a minimum of 1. Be capable of reducing power consumption by a minimum of Be capable of reducing power consumption by a minimum of 65 percent when the dimmer is at its lowest light level,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

i l f il ddcausing premature lamp failure; andand3. Be listed by a rating lab recognized by the International Code

Council (ICC) as being in compliance with Underwriters Laboratories Standards, andand




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 the level set by the dimmer, shall not be overridden by 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

g id f ti h ll b t ll d b th emergency override function shall be controlled by the emergency override.

5. If the device is a stepped dimmer, shall include an off position to turn lights completely off.


Question

I am doing minor renovations to my kitchen that has six 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 Does this luminaire have to be a high efficacy luminaire?be a high efficacy luminaire?

Answer

Yes, Yes, all new luminaires must be high efficacy until at must be high efficacy until at least 50% of the total lighting wattage comes from least 50% of the total lighting wattage comes from high efficacy luminaires high efficacy luminaires (§152 (b) 1 and §152 (b) 2).




EnergyStar CFL Information


How Much Light?

"Warm light 60" means that this CFL provides the same light as a 60"Warm light 60" means that this CFL provides the same light as a 60--watt watt incandescent bulb.incandescent bulb.

"Warm" indicates a color temperature between 2700"Warm" indicates a color temperature between 2700--3000K. 3000K. 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

i l h i d b lb l ias equivalent to the incandescent bulb you are replacing.

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 CFLs that produce light closer to the color of daylight (color temperatures above 3000K) may appear brighter because daylight (color temperatures above 3000K) may appear brighter because the color of the light is less yellowthe color of the light is less yellow..




Incandescent ENERGY STARBulbs Qualified Light Bulbs

Watts lumens Watts

40 450 9 to 13

60 800 13 to 15

75 1 100 18 to 2575 1,100 18 to 25

100 1,600 23 to 30

150 2,600 30 to 52


Choosing the right color:

Light color is measured on a temperature scale referred to 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 3000Kcolor of incandescent bulbs at 2700-3000K.

For a whiter light, look for bulbs marked 3500-4100K.

For bluer white light, look for bulbs marked 5000-6500K.





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.




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 timea time.

Choose 3 for 3. Only use bulbs labeled as three-way on three-way sockets.


Don’t dim a non-dimmable. Only use bulbs labeled as dimmable on dimmer switches.

Check your controls. Most photocells, motion sensors and 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 cansreflectors are best used in recessed 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.




I d Ai Q lit d Indoor Air Quality and Mechanical Ventilation

2008 Title 24 Ventilation Basics

Indoor Air Quality andMechanical Ventilation—§150(o) and 152(a)

With the 2008 update, With the 2008 update, all lowall low--rise residential buildings rise residential buildings are required to have a whole house ventilation are required to have a whole house ventilation system and satisfy other requirements to achieve system and satisfy other requirements to achieve acceptable indoor air quality.acceptable indoor air quality. The CEC adopted the The CEC adopted the requirements of requirements of ASHRAE Standard 62.2ASHRAE Standard 62.2--2007, 2007, except that opening and closing windowsexcept that opening and closing windows (although (although permitted by ASHRAE) permitted by ASHRAE) is not an acceptable option in is not an acceptable option in California.California.

Page 22008 Title 24 Ventilation Basics


Indoor Air Quality and Mechanical Ventilation Page 1

Ventilation for Indoor Air Quality §150(o)

All dwelling units All dwelling units shall meet the requirements shall meet the requirements of ANSI/ASHRAE Standard 62 2 of ANSI/ASHRAE Standard 62 2 Window Window of ANSI/ASHRAE Standard 62.2. of ANSI/ASHRAE Standard 62.2. Window Window operation is not a permissible method of operation is not a permissible method of providing the Whole Building Ventilationproviding the Whole Building Ventilationrequired in Section 4 of that Standard.required in Section 4 of that Standard.


Ventilation for Indoor Air Quality—CONTINUED

The indoor air quality requirements are not The indoor air quality requirements are not triggered for renovationstriggered for renovationstriggered for renovations.triggered for renovations.





The typical solutions are described in the following The typical solutions are described in the following section.section.

Kitchens and bathrooms Kitchens and bathrooms shall have shall have local exhaust local exhaust systems vented to the outdoors.systems vented to the outdoors.

Clothes dryers Clothes dryers shall be shall be vented to the outdoors.vented to the outdoors.

Ventilation air Ventilation air shall come from the out of doors and shall come from the out of doors and shall shall not be transferred from adjacent dwelling units, not be transferred from adjacent dwelling units, garages or crawlspaces.garages or crawlspaces.



Ventilation system controls Ventilation system controls shall be labeled and the home shall be labeled and the home owner shall be provided with instructions owner shall be provided with instructions on how to operate on how to operate h h the system.the system.

Combustion appliances Combustion appliances shall be shall be properly properly vented and air systems shall be vented and air systems shall be designed to prevent back drafting.designed to prevent back drafting.

The wall and openings between the house and the garage shall The wall and openings between the house and the garage shall b l db l dbe sealedbe sealed..

Habitable rooms shall have windows with a ventilation area of at Habitable rooms shall have windows with a ventilation area of at least 4% of the floor area least 4% of the floor area (see 3.5.2).(see 3.5.2).





Mechanical systems Mechanical systems including heating and air conditioning including heating and air conditioning systems that supply air to habitable spaces shall have systems that supply air to habitable spaces shall have MERV 6 MERV 6 filt filt b tt b ttfilters filters or better.or better.

Air inlets Air inlets (not exhaust) shall be (not exhaust) shall be located away from known located away from known contaminants.contaminants.

Air moving equipment Air moving equipment used for to meet either the whole building used for to meet either the whole building ventilation requirement or the local exhaust requirement ventilation requirement or the local exhaust requirement shall shall be rated in terms of air flow and soundbe rated in terms of air flow and sound Continuously operating Continuously operating be rated in terms of air flow and sound.be rated in terms of air flow and sound. Continuously operating Continuously operating fans shall be less than 1.0 sonefans shall be less than 1.0 sone, , and and intermittently operated intermittently operated fans shall be less than 3.0 sonefans shall be less than 3.0 sone. . Remotely located equipment Remotely located equipment is excepted.is excepted.


Typical Solutions for Whole Building Ventilation

There are three generic solutions to meeting the There are three generic solutions to meeting the outside air ventilation requirement:outside air ventilation requirement:qq

Exhaust ventilation,Exhaust ventilation,

Supply ventilation, Supply ventilation, or aor a

Combination of supply and exhaust ventilation. Combination of supply and exhaust ventilation. IfIfthe supply and exhaust flows are within 10% of the supply and exhaust flows are within 10% of the supply and exhaust flows are within 10% of the supply and exhaust flows are within 10% of each other this is each other this is called a balanced ventilation called a balanced ventilation system.system.




Exhaust VentilationExhaust Ventilation Exhaust Ventilation is usually achieved by a is usually achieved by a quiet ceilingquiet ceiling--

mounted bath fan or remote mounted inline or exteriormounted bath fan or remote mounted inline or exterior--d fd fmounted fans.mounted fans.

Air is drawn from the house by the exhaust fan and outdoor air enters Air is drawn from the house by the exhaust fan and outdoor air enters the house through leaks in the building envelope. the house through leaks in the building envelope. Because the Because the leaks are generally uniformly scattered throughout the house, leaks are generally uniformly scattered throughout the house, outdoor air entering the houseoutdoor air entering the housedoes not generally create does not generally create drafty or uncomfortable drafty or uncomfortable conditions.conditions.


Many high quality bath fans are available in the Many high quality bath fans are available in the 30 to 150 30 to 150 cfm cfm size range and are quiet enough to be used size range and are quiet enough to be used continuously. continuously. One or more fans of this size will meet the One or more fans of this size will meet the requirements of most homes.requirements of most homes.

The exhaust fan can be a dedicated IAQ fan or it The exhaust fan can be a dedicated IAQ fan or it can be a can be a more typical bath fan that is used for both whole more typical bath fan that is used for both whole building ventilation and local ventilation.building ventilation and local ventilation.




Supply VentilationSupply 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.


Central Fan-Integrated Ventilation System

Central FanCentral Fan--Integrated Ventilation System Integrated Ventilation System is a is a central forced air central forced air heating and/or cooling system heating and/or cooling system which is intended to operate on a which is intended to operate on a regular basis to bring in outdoor ventilation air and/or distribute air regular basis to bring in outdoor ventilation air and/or distribute air regular basis to bring in outdoor ventilation air and/or distribute air regular basis to bring in outdoor ventilation air and/or distribute air around the home for comfort and ventilation even when heating around the home for comfort and ventilation even when heating and cooling are not needed.and cooling are not needed.

This strategy, This strategy, uses the uses the negative pressure in the negative pressure in the return plenum to pull in return plenum to pull in

td i d th h ittd i d th h itoutdoor air and then push itoutdoor air and then push itthrough the air handler.through the air handler.




Combination VentilationCombination systems Combination systems use both exhaust fans and use both exhaust fans and

supply fans.supply fans. If both fans supply the same air flow If both fans supply the same air flow pp ypp y pp ypp ythe system is balanced and the house has a the system is balanced and the house has a neutral pressure, as opposed to a supply neutral pressure, as opposed to a supply ventilation system which results in a positive ventilation system which results in a positive pressure or an exhaust ventilation system which pressure or an exhaust ventilation system which results in a negative pressureresults in a negative pressureresults in a negative pressure.results in a negative pressure.


Combination Ventilation—CONTINUED

Combination systems are often integrated devices, are often integrated devices, sometimes with a heat exchanger or heat recovery sometimes with a heat exchanger or heat recovery g yg ywheel, the supply and exhaust airstreams are typically wheel, the supply and exhaust airstreams are typically of equal flow. of equal flow. Combination systems can also consist of a Combination systems can also consist of a mixture of supply fans and exhaust fans.mixture of supply fans and exhaust fans.




Ventilation Flow Rate(Chapter 4 of ASHRAE 62.2)

The continuous ventilation rate is one cubic foot per minute The continuous ventilation rate is one cubic foot per minute (cfm) for each 100 ft(cfm) for each 100 ft22 of floor area plus 7.5 cfm for each of floor area plus 7.5 cfm for each occupant. The number of occupants is approximated as occupant. The number of occupants is approximated as the number of bedrooms plus one.the number of bedrooms plus one.

Equation 4Equation 4--11

Ventilation Rate (cfm) = CFA/100 + [7.5 x (Number Bedrooms +1)]Ventilation Rate (cfm) = CFA/100 + [7.5 x (Number Bedrooms +1)]Ventilation Rate (cfm) CFA/100 + [7.5 x (Number Bedrooms +1)]Ventilation Rate (cfm) CFA/100 + [7.5 x (Number Bedrooms +1)]

Table 4Table 4--7 7 may be used to determine the required may be used to determine the required ventilation.ventilation.


Table 4-7 Continuous Ventilation Rate




Example 4-6–Required Ventilation

QuestionQuestion

What is the required continuous ventilation rate required What is the required continuous ventilation rate required What is the required continuous ventilation rate required What is the required continuous ventilation rate required for a 3 bedroom, 1,800 ftfor a 3 bedroom, 1,800 ft22 townhouse.townhouse.

AnswerAnswer

48 cfm.48 cfm.

This is calculated as: This is calculated as:

1800/100 + (3+1)*7.5 = 48 cfm. 1800/100 + (3+1)*7.5 = 48 cfm.

Using Using Table 4Table 4--7, 7, the required ventilation rate would be 60 cfm.the required ventilation rate would be 60 cfm.


Example 4-6 – Required Ventilation—CONTINUED

QuestionQuestion

The house I am building has a floor area of 2 240 ftThe house I am building has a floor area of 2 240 ft22 and 3 and 3 The house I am building has a floor area of 2,240 ftThe house I am building has a floor area of 2,240 ft and 3 and 3 bedrooms. My calculations come out to 52.4 cfm. bedrooms. My calculations come out to 52.4 cfm. Can I Can I use a 50 cfm fan?use a 50 cfm fan?

AnswerAnswer

NoNo, , a 50 cfm fan does not meet the standard. You would a 50 cfm fan does not meet the standard. You would need to need to select the next larger size select the next larger size fan, such as a unit fan, such as a unit rated at 55 cfm or 60 cfm. rated at 55 cfm or 60 cfm. If you use Table 4If you use Table 4--7 to select 7 to select the fan size, you get 60 cfm.the fan size, you get 60 cfm.




Ventilation Rate for Combination Systems

When a combination ventilation system is used, When a combination ventilation system is used, meaning that both supply and exhaust fans are meaning that both supply and exhaust fans are installed, the provided ventilation rate is the larger of installed, the provided ventilation rate is the larger of the total supply airflow or the total exhaust airflow. the total supply airflow or the total exhaust airflow. The airflow rates of the supply and exhaust fans The airflow rates of the supply and exhaust fans cannot be added together.cannot be added together.


Intermittent VentilationIn 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 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.




Intermittent Ventilation—CONTINUED

Figure 4Figure 4--23 23 shows the multiplier based on the total shows the multiplier based on the total hours per day of fan operation. There is very little hours per day of fan operation. There is very little need to increase fan flow when the fans operate for need to increase fan flow when the fans operate for more than about 20 hours per day. more than about 20 hours per day. However, the However, the required flow rate can be 10 to 20 times greater required flow rate can be 10 to 20 times greater when the fans operate for less than 6 hours per day.when the fans operate for less than 6 hours per day.


Equation 4-2The multipliers in Figure 4Figure 4--23 23 are determined from the

following equation, which can be used in lieu of the graph.

Qf = Qf = QrQr/(/(efef))

Where:Qf = fan flow rateQf = fan flow rate

Qr = ventilation Qr = ventilation air requirement (continuous)air requirement (continuous)

e = ventilation effectiveness, e = ventilation effectiveness, (Table 4(Table 4--8, next slide)8, next slide)

f = fractional onf = fractional on--time. time.




Table 4-8–Ventilation Effectiveness for Intermittent Fans

Intermittent ventilation systems have to be automatically controlled Intermittent ventilation systems have to be automatically controlled Intermittent ventilation systems have to be automatically controlled Intermittent ventilation systems have to be automatically controlled by a timer or other device that assures that they will operate the by a timer or other device that assures that they will operate the minimum amount of time needed to meet the ventilation minimum amount of time needed to meet the ventilation requirement. requirement. The automatic controls shall make sure that the fan operates at least one hour in twelve.


Table 4-8–Ventilation Effectiveness for Intermittent Fans

Intermittent ventilation systems have to be automatically controlled Intermittent ventilation systems have to be automatically controlled by a timer by a timer or other device that assures that they will operate the or other device that assures that they will operate the minimum amount of time needed to meet the ventilation minimum amount of time needed to meet the ventilation minimum amount of time needed to meet the ventilation minimum amount of time needed to meet the ventilation requirement. requirement. The automatic controls shall make sure that the fan The automatic controls shall make sure that the fan operates at least one hour in twelve.operates at least one hour in twelve.

Determine Intermittent CFMDetermine Intermittent CFMStep 1:Determine fractional onStep 1:Determine fractional on--time, time, EXAMPLE: With the fan running EXAMPLE: With the fan running

2 hours every 12 hours, 2/12 = 2 hours every 12 hours, 2/12 = 0.167 = f0.167 = fStep 2:Locate the Daily Fractional OnStep 2:Locate the Daily Fractional On--time and take the time and take the

Effectiveness factor from that line. Effectiveness factor from that line. EXAMPLE: .33EXAMPLE: .33Step 3:CFA x 0.01 +( (bedrooms + 1) X 7.5) / Step 3:CFA x 0.01 +( (bedrooms + 1) X 7.5) / (0.167 x .33)(0.167 x .33)

EXAMPLE: EXAMPLE: 1,800 x 0.01 + ((3 + 1) x 7.5) 1,800 x 0.01 + ((3 + 1) x 7.5) / 0.05511 = 871 CFM/ 0.05511 = 871 CFM




Control and OperationThe standard requires that the ventilation system have The standard requires that the ventilation system have

an override control which is readily accessible to the an override control which is readily accessible to the occupants. occupants. The “fanThe “fan--on” switch on a typical on” switch on a typical thermostat controlling the HVAC system and the wall thermostat controlling the HVAC system and the wall switch for an exhaust fan are both allowed as switch for an exhaust fan are both allowed as acceptable controls.acceptable controls.


Example 4-9–Control OptionsQuestionQuestionI plan to use a bathroom exhaust fan to provide the ventilation for a I plan to use a bathroom exhaust fan to provide the ventilation for a

house. The fan is designed to be operated by a typical wall switch. Do house. The fan is designed to be operated by a typical wall switch. Do I need to put a label on the wall plate to comply with the requirement I need to put a label on the wall plate to comply with the requirement that controls be “appropriately labeled”?that controls be “appropriately labeled”?

AnswerAnswer

Yes. Yes. If the exhaust fan were serving only the local exhaust If the exhaust fan were serving only the local exhaust requirement for the bathroom, then a label would not be required. requirement for the bathroom, then a label would not be required. q , qq , qSince the fan is providing whole house ventilation, a label is Since the fan is providing whole house ventilation, a label is needed to inform the occupant of that.needed to inform the occupant of that.




Heat Recovery or Energy Recovery Ventilators

Systems using Systems using Heat Recovery or Energy Recovery Heat Recovery or Energy Recovery ventilatorsventilators may need to account for the heat may need to account for the heat recovery benefit in the performance calculation to recovery benefit in the performance calculation to make up for their high energy use.make up for their high energy use.


Ventilation RateA minimum flow of A minimum flow of 100 cfm 100 cfm is required for the is required for the rangerange

hood hood and and 50 cfm 50 cfm for the for the bath fanbath fan. . The 100 cfm The 100 cfm i f h h d i /h d i f h h d i /h d requirement for the range hood or microwave/hood requirement for the range hood or microwave/hood

combination is the minimum to adequately capture combination is the minimum to adequately capture the moisture and other products of cooking and/or the moisture and other products of cooking and/or combustion.combustion.

The kitchen exhaust requirement can also be met The kitchen exhaust requirement can also be met with with either a ceiling or wall mounted exhaust fan or with a either a ceiling or wall mounted exhaust fan or with a either a ceiling or wall mounted exhaust fan or with a either a ceiling or wall mounted exhaust fan or with a ducted fan or ducted ventilation system that ducted fan or ducted ventilation system that provides at least 5 air changes of the kitchen provides at least 5 air changes of the kitchen volume per hourvolume per hour..




Example 4-13–Is an Intermittent Range Hood Required?

Question

I am building a house with a kitchen that is 12’ x 14’ with a 10 foot ceiling. What size ceiling fan is required?

Answer

The kitchen volume is 12’ x 14’ x 10’ = 1680 cubic feet5 ACH

= 8400 ft3/hour8400/60 min/hr = 140 cfm

So this kitchen must have a ceiling or wall fan of 140 cfm or a 100 cfm vented range hood.


Clothes DryersAll laundry rooms must be built with a duct to the All laundry rooms must be built with a duct to the

outdoors, designed to be connected to the dryer. outdoors, designed to be connected to the dryer. Devices which allow the exhaust air to be diverted Devices which allow the exhaust air to be diverted into the indoor space to provide extra heating are into the indoor space to provide extra heating are not permitted. not permitted. This requirement is consistent with This requirement is consistent with existing clothes dryer installation and design existing clothes dryer installation and design standards.standards.




GaragesIf an If an air handling unit (furnace) is located in the garage, air handling unit (furnace) is located in the garage,

or return ducts are located in the garage or return ducts are located in the garage (regardless (regardless of the air handler location) of the air handler location) the entire duct system the entire duct system must meet the sealed and tested ducts criteria.must meet the sealed and tested ducts criteria.


Example 4-16–GaragesQuestionQuestion

The building designer located the air handler in the The building designer located the air handler in the garage. The main return trunk from the dwelling is connected to the air handler. Is this acceptable?

Answer

Yes, provided that the duct system is leak tested at 25 Pa. and sealed, if necessary, to have leakage no greater than 6% of the total fan flow.




Minimum FiltrationThe standard requires that particulate air filtration The standard requires that particulate air filtration of of

no less than MERV 6 no less than MERV 6 efficiency be installed in any efficiency be installed in any o ess t a 6o ess t a 6 e c e cy be sta ed a ye c e cy be sta ed a yHVAC systemHVAC system having more than 10 ft of ductwork.having more than 10 ft of ductwork.The particulate filter must be installed such that all The particulate filter must be installed such that all of the air circulated through the furnace or air of the air circulated through the furnace or air handler is filtered prior to passing through the handler is filtered prior to passing through the thermal conditioning portion of the system.thermal conditioning portion of the system.t e a co d t o g po t o o t e systet e a co d t o g po t o o t e syste


Airflow RatingThe air flow rating The air flow rating can be verified in one of two ways.can be verified in one of two ways.

The The system can be tested after installation to show that the system can be tested after installation to show that the The The system can be tested after installation to show that the system can be tested after installation to show that the delivered airflow meets the design requirementdelivered airflow meets the design requirement. .

A prescriptive alternate is available for simple exhaust systems A prescriptive alternate is available for simple exhaust systems where the where the fan has a certified airflow rating that meets or fan has a certified airflow rating that meets or exceed the required airflow when measured at 0.25” exceed the required airflow when measured at 0.25” iwciwc. .

AndAndAndAnd

the the duct system meets the requirements of Table 4duct system meets the requirements of Table 4--9.9.




Table 4-9


Example

2008 Title 24 Ventilation Basics Page 36



Example 4-20–Prescriptive Duct Sizing

QuestionQuestion

I need to provide 75 cfm of continuous ventilation I need to provide 75 cfm of continuous ventilation I need to provide 75 cfm of continuous ventilation, I need to provide 75 cfm of continuous ventilation, which I plan to do using a central exhaust fan. I which I plan to do using a central exhaust fan. I plan to connect the fan to a roof vent termination plan to connect the fan to a roof vent termination using flex duct. The duct will be about 8 feet long, using flex duct. The duct will be about 8 feet long, with no real elbows, but some slight bends in the with no real elbows, but some slight bends in the duct. What size duct do I need to use?duct. What size duct do I need to use?


Example 4-20–Prescriptive Duct Sizing—CONTINUED

AnswerAnswerFrom From Table 4Table 4 9 9 using the using the 80 cfm 80 cfm flex duct column we find that theflex duct column we find that theFrom From Table 4Table 4--9, 9, using the using the 80 cfm, 80 cfm, flex duct column, we find that theflex duct column, we find that the

maximum length with 4” duct is 3 feetmaximum length with 4” duct is 3 feet, , so you cannot use 4” duct. so you cannot use 4” duct. With 5” duct With 5” duct the the maximummaximum length is 70 feetlength is 70 feet, , so that will clearly be so that will clearly be adequate. Even adequate. Even if the bend in the duct is treated as an elbowif the bend in the duct is treated as an elbow, the , the allowable lengthallowable lengthonly drops to 55only drops to 55feet,feet, more than more than feet,feet, more than more than adequate for theadequate for the8 feet required.8 feet required.




Multi-Branch Exhaust DuctingThe first restriction is that if more than one exhaust fan The first restriction is that if more than one exhaust fan

in a dwelling shares a common duct, then each fan in a dwelling shares a common duct, then each fan must be equipped with a backdraft damper so that must be equipped with a backdraft damper so that air exhausted from one bathroom or unit is not air exhausted from one bathroom or unit is not allowed to go into another space.allowed to go into another space.


Questions?




Download - New Title 24 Standards For Lighting Windows And Ventilation

Top Related