cres23: daylight harvesting & controls...daylight concerns: • sky factor • building...

111
® 2012 Crestron Electronics, Inc. Specifications subject to change. All copyrights and trademarks property of their respective owners. CRES23: Daylight Harvesting & Controls Presented by: Michael Block National Design Manager [email protected] Update 08-16-12

Upload: others

Post on 04-Jul-2020

1 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

® 2012 Crestron Electronics, Inc. Specifications subject to change. All copyrights and trademarks property of their respective owners.

CRES23:

Daylight Harvesting & Controls

Presented by:

Michael Block

National Design Manager

[email protected]

Update 08-16-12

Page 2: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting & Controls

Crestron Electronics, Inc. is a Registered Provider with The American Institute of Architects

Continuing Education Systems. Credit earned on completion of this program will be reported to CES

Records for AIA members. Certificates of Completion for non-AIA members are available on request.

This program is registered with the AIA/CES for continuing professional education. As such, it does

not include content that may be deemed or construed to be an approval or endorsement by the AIA of

any material of construction or any method or manner of handling, using, distributing, or dealing in

any material or product. Questions related to specific materials, methods, and services will be

addressed at the conclusion of this presentation.

2

Crestron Course #: CRES23:

Page 3: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

1. Define Daylighting and discuss the various benefits &

concerns associated with it related to Commercial

Architecture.

2. Define Daylighting Harvesting and gain an overview of the various

Daylight Harvesting Techniques available.

3. Become familiar with the new changes in the Energy Codes that now

require Daylight Harvesting.

4. Understand the terminology & control techniques necessary for a

successful Daylight Harvesting system.

Learning Objectives:

By the end of this lecture the attendee will…

3

Page 4: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

What is Daylighting?

4

Page 5: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

What is Daylighting?

5

• Daylighting’s objective is…to minimize the amount of

artificial light thereby reducing electricity costs.

• Daylighting is… the practice of placing windows or other

openings and reflective surfaces so that during the day natural

light provides effective internal lighting.

• Daylighting can also…lower HVAC costs. Properly controlled

natural daylighting generates hardly any heat compared to its

electrical lighting counterpart.

Page 6: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylighting Techniques

6

Electric Light

Vertical

Glazing

Light

Wells

Sky

Light

Light

Pipes Glass

Walls

Photo-

voltaics

• Light Shelves

• Light Wells

• Sky Lights

• Light Pipes

• Vertical Glazing

• Glass Interior

Walls

• Photovoltaics

Light

Shelf

Page 7: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylighting Benefits

7

Page 8: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of Daylighting:

8

• Full Color Spectrum

Page 9: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of Daylighting:

9

• Full Color Spectrum

• Aids bodies natural

Circadian Rhythms

& prevents

Seasonal Affective

Disorder

Page 10: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of Daylighting:

10

• Full Color Spectrum

• Aids bodies natural

Circadian Rhythms &

prevents Seasonal

Affective Disorder

• Saves Energy

Page 11: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of Daylighting:

11

• Full Color Spectrum

• Aids bodies natural

Circadian Rhythms &

prevents Seasonal

Affective Disorder

• Saves Energy

• Improves end-user

satisfaction/performance

& consumer sales

Page 12: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of Daylighting:

12

• Full Color Spectrum

• Aids bodies natural Circadian

Rhythms & prevents Seasonal

Affective Disorder

• Saves Energy

• Improves end-user

satisfaction/performance &

consumer sales

• High Demand, High Value,

Corporate Image

Page 13: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylighting Concerns

13

Page 14: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

Clear Sky

Partly Cloudy

Overcast

14

• Sky Factor

Page 15: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

15

• Sky Factor

Amount of sun varies every day

Number of days of sun per year varies with every city

‘Sunnier’ cities will have higher ROI and faster payback than others

Control system needs to be commissioned appropriately for the climate type

Commissioning requirements should be included in the programming scope

and the CSI specifications to suit the clients expectations

Example: Miami has quickly passing clouds, select a slower ‘Response time’ (2min.)

Seattle has slowly passing clouds, select a faster ‘Response time’ (30 sec.)

Clear Sky

Partly Cloudy

Overcast

Page 16: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

• Sky Factor

• Building Orientation

16

Page 17: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

• Sky Factor

• Building Orientation

17

South-facing windows are most advantageous

for daylighting and for moderating seasonal

temperatures. They allow most winter sunlight

into a building but little direct sun during the

summer, especially when properly shaded.

North-facing windows are also advantageous

for daylighting. They admit relatively even,

natural light, producing little glare and almost no

unwanted summer heat gain.

Although east- and west-facing windows

provide good daylight penetration in the morning

and evening, respectively, they should be limited.

They may cause glare, admit a lot of heat during

the summer when it is usually not wanted, and

contribute little to solar heating during the winter.

Page 18: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

18

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

Page 19: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

19

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

Understand that ROI for a project in a city

with buildings in close proximity will vary

from the same building in a rural setting or in

a less crowded environment

Page 20: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

• Solar Heat Gain

20

Page 21: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

• Solar Heat Gain

Low SHGC glass

(Solar Heat Gain Coefficient)

Low U-Factor Glass (Heat Flow through

the window)

Low AL (Air Leakage)

Install Manual or

Motorized Shades !!!!!!

Install multiple layers of shades

21

Page 22: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

• Solar Heat Gain

• Glare

Too permanent, ruins façade

of the building

Makes it hard to work

22

Page 23: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

• Solar Heat Gain

• Glare

Size windows properly

Install Manual or

Motorized Shades !!!

23

Page 24: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

• Solar Heat Gain

• Glare

Install Manual or

Motorized Shades !!!

Consider 2 layers of

shades to correctly

manage daylight:

- translucent fabric

- black out shades

Solar Tracking

Install manual override

Integrate with lighting

control & AV scenes

within the room

Summer solstice, southern latitude

Winter solstice, southern latitude

24

Page 25: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating
Page 26: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

• Solar Heat Gain

• Glare

• What is the Return on

Investment (ROI)?

energy savings > the price tag?

26

Page 27: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

“What is the true ROI for Daylight Harvesting?”

Part 1 – The cost ($) of the Daylight Harvesting System

Part 2 – The value ($) in Energy Savings

Part 3 – The value ($) of Happy Tenants…priceless

> $0.00 then a Positive Return on Investment !

Daylight Concerns:

• Sky Factor

• Building Orientation

• Obstructions

• Solar Heat Gain

• Glare

• What is the Return on

Investment (ROI)?

27

Page 28: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylighting Study

28

Page 29: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

In a recent study by Lawrence Berkeley National Labs they attempted to answer two very

important questions related to Daylight Harvesting …

29

“Where are the Primary & Secondary Daylighting

Zones located?”

“How much Energy is saved in each Zone?”

Page 30: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylighting Study:

30

6’

(10-15’) to 25’ 25’+

9’

Vertical Glazing: Primary & Secondary Zones

Example 1 Example 2

Third

Zone

Primary

Zone

Secondary

Zone

11-31’ 0-11’

Primary

Zone

Secondary

Zone

0 to (10-15’)

Page 31: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylighting Study:

31

Horizontal Glazing: Primary & Secondary Zones

Primary Zone

h x 70% h x 70%

35° 35°

Secondary

Zone Secondary

Zone

Skylight

h

Larger quantities of light

than Vertical Glazing, but

lacks views to the exterior

Cannot be used for LEED

Indoor Environmental

Quality Credit 8.2

Page 32: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylighting Study: Energy Savings

In a recent study by Lawrence Berkeley National Labs, they

compared the energy for one year from a space with daylight

harvesting to a space without daylight harvesting and found…

32

9’

11-31’

Example B: LBNL Study

- 9’ Glass Walls, all 4 sides of the building

- Low Partition, Open Work Stations

- Daylight Dimming Techniques used

0-11’

Primary Zone Energy Savings:

West facing walls - saved 30%

NW & SW facing walls - saved 50- 60%

Secondary Zone Energy Savings:

West facing walls - saved 10%

NW & SW facing walls - saved 25- 40%

30-60%

Energy

Savings

10-40%

Energy

Savings

Page 33: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

What is Daylight

Harvesting?

33

Page 34: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

What is Daylight Harvesting?

34

A control system used in sustainable architecture that reduces the use

of artificial lighting with electric lamps in building interiors when natural

daylight is available, in order to reduce energy consumption.

Page 35: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting

Techniques

35

Page 36: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting: Open Loop Systems

36

Open Loop Sensor: Example #1

• The photosensor detects the amount of

available daylight only

• It can be positioned:

• on the building's exterior wall or roof

• or inside the building facing the skylight

h x 70% h x 70%

Skylight

Typical Open Loop

Photosensor

h

35° 35°

Example #1

Page 37: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting: Open Loop Systems

37

Open Loop Sensor: Example #2

• The photosensor detects the amount of

available daylight only

• It can be positioned:

• on the building's exterior wall or roof

• or inside the building facing the skylight

• or inside the building facing the window

• Allows multiple zones of fixtures to be

controlled with a single photosensor

Typical Open Loop

Photosensor

h

h 2h

Example #2

Page 38: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting: Closed Loop Systems

38

Closed Loop:

• The photosensor detects the combination of

daylight and electric light

• It should be positioned:

• away from direct sunlight

• away from direct artificial light

• where it can measure reflected light off

a surface from both the natural and

artificial light

• Allows you to define a single set point and

vary the zones to achieve it

• Each independently controlled zone requires

a photosensor

Typical Closed Loop

Photosensor

h 2h

h

Example

Page 39: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

39

Ten Design Principles for Daylighting • Configure room so that occupied floor area is

within daylighting zones, typically about 15

feet from the window wall or below skylights.

• Elongate wings of the building on east/west

axis to avoid glare and solar heat gain

• Bring the light in high. Windows high on the

wall allow light to penetrate further into the

space.

• Use skylights to daylight areas without easy

access to windows.

• Let daylight in from more than one side of the

room when possible.

• Provide views where appropriate, but diffuse

or block direct sunlight to avoid glare/heat.

• Use light colored interior surfaces to reduce

luminance contrast and improve coverage.

• Control first costs by avoiding excessive

glazing.

• Promote “daylighting behaviour” within the

building by educating occupants to open

blinds when possible.

• Use automated controls to dim or switch off

electric light when daylight is sufficient.

Page 40: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Switching

Vs. Daylight Dimming

40

Page 41: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting: Switching or Dimming?...

41

Recommended for:

Day lit spaces where non-detailed tasks take

place (ie: warehouse, factory, gym)

Day lit spaces where switching is not

distracting

Daylight Bi-Level Switching

Advantages

• 3+ levels of lighting

• Cheaper than full dimming

• Additional energy savings

Disadvantages

• Somewhat distracting

• Additional ballast(s) &

wiring needed

• Additional cost vs switching

Page 42: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting: Switching or Dimming?...

42

Recommended for:

Day lit spaces where detailed tasks are being

performed (Classrooms, Labs, Office Spaces)

Day lit spaces where exact fc levels are needed

Daylight Dimming – Unlimited levels of daylight can be reached.

Advantages

• Exact fc level can be

maintained at all times

• Most comfortable for clients

• Highest energy savings

Disadvantages

• $ Dimming ballast/driver

needed

• Commissioning may require

more time

Page 43: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting

Codes

43

Page 44: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting Codes: ASHRAE 189.1 - 2010

44

Automatic Lighting Controls - expanded to include:

- daylight harvesting

- manual-ON and bi-level occupancy sensing

- bi-level switching in some stack and egress and outdoor

applications.

Submetering: Major building systems such as HVAC & lighting

are required to be submetered and the data fed to a data

acquisition system for storage and later retrieval.

On-Site Renewables: Buildings must provide for future

installation of on-site renewable energy systems.

LPD: Lighting power densities capped at 90% of those in 90.1-07

Peak Load Shedding: In addition, buildings must contain

automatic demand-response systems enabling peak electric

demand to be reduced by at least 10%.

Page 45: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting Codes: ASHRAE 90.1 - 2010

45

Daylighting Requirements:

Developed in conjunction with Title 24

Requires the installation of skylights when appropriate

Daylit areas must have multi-level control:

• At least 2 levels of output, 0-35% & 50-70%, All On

• Or Continuous Dimming

Top Lighting: (Skylights & Rooftop Monitors)

- Applied if daylight area under skylight

and rooftop monitors is >4000 ft2

Side Lighting: (Vertical Glazing)

- Applied if sidelit area is >1000ft2

Page 46: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

© 2015 Crestron Electronics, Inc.

Daylight Responsive Control

+ C405.2.3

• Daylight harvesting required:

• Spaces with >150W general lighting within daylight zone

• Exceptions: healthcare, dwelling/sleeping units, food/drink consuming areas, shops and stores.

• Exception: area of fenestration is <24sqft

• Exception: distance from fenestration to nearest obstruction is shorter than the distance from the bottom of the fenestration to the top of the obstruction

• The daylight harvesting controls must be readily accessible

• The daylight harvesting controls must be capable of being calibrated within the space they are affecting

Page 47: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting

Controls &

Commissioning

47

Page 48: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting Controls: Photosensors

48

Photosensors

Used to measure the quantity of daylight in the space then determine the

amount of dimming or switching required to maintain the design work

plane illuminance level.

Typical Open Loop

Photosensor

Typical Closed Loop

Photosensor

• 0-10V signal

• 3-300, 30 to 3000, or 60 to 6000

footcandle range

• 0-10V signal

• Measures 0-70 footcandles

Page 49: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting Controls: Direct Method vs. Processors

49

Processor Method - A processor is the brains of a Daylight Harvesting control system. It

receives data input from the photocell and then sends a signal to:

- the ballast or light fixture to turn on/off/dim

- keypads and/or touchpanels for override

- facility energy management & monitoring system

- shade system

* It also makes it easy to commission and change

the settings of the photocell remotely as needed.

Direct Method - Wiring the lighting ballast & photocell together.

Typical for some open-loop systems. Extreme limitations in

control capability. Not recommended

Page 50: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Harvesting: Commissioning Terminology

50

Response Time – defines how quickly the system reacts to changes in light levels

Minimum Dim Level – defines the lowest level a dimmer may output (can be used to

prevent the lights from turning completely off when dimming)

Dim Level To Photosensor Relationship (Open-Loop) – defines dimmer output levels

in relationship to open-loop photosensor readings

Desired Light Level (Closed-Loop) – defines the desired light level in the space

Photosensor Range – set photosensor fc range (3-300, 30-3000, 60-6000, etc.)

(Sensor voltage output to light level relationship needs to be defined in the system)

The following settings are common parameters when configuring the

operation of a daylight harvesting system:

Page 51: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

51

To Think About…

There are various techniques available to incorporate daylight harvesting into a

commercial project

The benefits of daylight harvesting (including energy savings) outweigh any of the

prior concerns due to the new technology, programs, & simple commissioning

tools that are now available from various manufactures

The only way we will truly reach future sustainable goals is to integrate Daylight

Harvesting into more than just lighting, and then look at the big picture…

…Integrated Building Technology.

Page 52: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

This concludes the 1 hour Crestron

AIA Continuing Education Seminar on:

CRES12:

Daylight Harvesting & Controls

Thank You.

Please feel free to complete the

course evaluation forms.

Page 53: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

® 20012 Crestron Electronics, Inc. Specifications subject to change. All copyrights and trademarks property of their respective owners.

CRES11:

Energy Codes & Integrated Building Technology

Presented by:

Michael Block National Design Manager

Update 08-16-12

Page 54: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Thank you!

Energy Codes & Integrated Building Technology

Crestron Electronics, Inc. is a Registered Provider with The American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion for non-AIA members are available on request.

This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

2

Crestron Course #: CRES11:

Page 55: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

3. Understand the benefits of a single-platform IBT solution from various stake-holder’s perspectives. Architect, Engineer, GC, EC, Facility Manager, Building Owner, etc.

2. Be able to define the term Integrated Building Technology (IBT) & the role it will fill in meeting today’s energy code requirements

1. Become familiar with evolution of the Energy Codes & Standards

Learning Objectives:

3

Page 56: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

A Global Presence

59 Offices, 90 Countries, 2500+ Employees, 300+ Engineers, Training Centers, 24/7/365 Support

Energy Codes &

Standards

4

Page 57: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Why have lighting controls become so important

over the past 35 years?...

5

Page 58: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…1975

ANSI/ASHRAE/IES Standard 90-1975: Energy Conservation in New Building Design

1975

1990 2030 2010

Initiated by the U.S. Federal Government Created in a response to the 1973 Oil Crisis National voluntary consensus standard Technical contributors were: ANSI, ASHRAE, IESNA Included standards for : Building Envelope, HVAC, Lighting,

& Water

1980 2000 2020

6

Page 59: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…1989

1989

The standard is updated for the first time 14% more stringent than the previous 1975 version Name changed slightly to what we know it today Still voluntary, but Fed funding becomes available

ANSI/ASHRAE/IES Standard 90.1-1989: Energy Standard for Buildings Except Low-Rise Residential Buildings

1990 2030 2010 1980 2000 2020

7

Page 60: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…1992

1992

DOE gets involved, voluntary adoption of energy standards is no longer an option EPAct required all states to adopt energy codes for commercial and high-rise multi-

family residential buildings at least as stringent as ASHRAE 90.1 – 1989 Some states & cities not only enforced the code, but exceeded: Promise of

incentives & federal funding (ex: California’s Title 24) Still spotty enforcement

EPAct 1992: U.S. Energy Policy Act of 1992

1990 2030 2010 1980 2000 2020

8

Page 61: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…1993

1993

In 1993 the USGBC is created

U.S. Green Building Council (USGBC):

USGBC was founded as a non-profit trade organization that promotes sustainability in how buildings are designed, built and operated

1990 2030 2010 1980 2000 2020

9

Page 62: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…1994

1994

In 1994 the ICC was created as a non-profit organization dedicated to developing a single set of broad & coordinated national construction codes

International Code Council (ICC):

Three founders of ICC were Building Officials and Code Administrators International (BOCA), International Conference of Building Officials (ICBO), and Southern Building Code Congress International (SBCCI)

1990 2030 2010 1980 2000 2020

10

Page 63: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…1998

1998

1990 2030 2010 1980 2000 2020

In 1998 the ICC released the first International Energy Conservation Code

International Energy Conservation Code (IECC):

Additional versions of the IECC have been released in 2000, 2003, 2006, 2009, and 2012

Every year the building industry gains more knowledge and technology that helps reduce the building energy consumption

11

Page 64: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…1998

1998

In 1998 the USGBC created LEED

U.S. Green Building Council (USGBC):

Leadership in Energy and Environmental Design

LEED is a recommended standard, not code

1990 2030 2010 1980 2000 2020

Many cities adopted LEED as a requirement for new construction

LEED Guides reference the latest ASHRAE 90.1 Energy Standard

12

Page 65: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…1999

1999

Standard 90.1 is updated again

ANSI/ASHRAE/IES Standard 90.1-1999: Energy Standard for Buildings Except Low-Rise Residential Buildings

1990 2030 2010 1980 2000 2020

Decision is made to make it a continuous maintenance standard & update it every 3 years like the IECC

Additional versions have been released in 2001, 2004, 2007, & 2010

13

Page 66: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…2004

2004

ANSI/ASHRAE/IES Standard 90.1-2004: Energy Standard for Buildings Except Low-Rise Residential Buildings

1990 2030 2010 1980 2000 2020

By 2004 it is ~12% more efficient than the 1999 standard

How much more efficient is each update?...

14

Page 67: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…2007

2007

By 2004 it is ~12% more efficient than the 1999 standard

ANSI/ASHRAE/IES Standard 90.1-2007: Energy Standard for Buildings Except Low-Rise Residential Buildings

By 2007 it is ~17% more efficient than the 1999 standard

1990 2030 2010 1980 2000 2020

How much more efficient is each update?...

15

Page 68: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…2010

ANSI/ASHRAE/IES Standard 90.1-2010: Energy Standard for Buildings Except Low-Rise Residential Buildings

By 2010 it is ~30% more efficient than the 1999 standard

The future?...

1990 2030 2010 1980 2000 2020

By 2004 it is ~12% more efficient than the 1999 standard

By 2007 it is ~17% more efficient than the 1999 standard

How much more efficient is each update?...

16

2010

Page 69: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Energy Codes & Standards…pre-2000

Energy Design:

- Controls requirements - W/ft2 requirements

Lighting Design:

- Recommended fc levels - Design concepts

1990 2030 2010 1980 2000 2020

Prior to 2000 an Engineer/Lighting Designer had the following on his/her desk…

17

Page 71: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating
Page 72: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Vacancy Sensor Requirement

• C405.2.1 – Specific areas required to have vacancy control:

• Classrooms, conference rooms, offices, break rooms, storage rooms, closets

• All enclosed spaces 300 sqft or less

– Vacancy function only, or occupancy to 50%

• Occupancy to 100% allowed in: – Hallways, lobbies, stairwells, restrooms, entrances

– Warehouses (special set of requirements)

Page 73: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Time Clock Requirement

• C405.2.2 – Every space that does NOT have occupancy/vacancy controls

must have time clock control

– Time clock functionality • Minimum 7-day unique clock

• Incorporate holiday schedule

• Have program back-up capabilities

• Must have an override switch – Only to turn lights on for 2 hours or less in spaces smaller than 5000sqft

» Exception: malls, auditorium, retail space, industrial facility

Page 74: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Dimming/Switching Requirement

• C405.2.2.2 – If a time clock is used, dimming/scene control is also

mandatory • Exception: where manual dimming is allowed and no time clock or

occupancy/vacancy: – Sleeping units, patient care, shop and lab rooms

– Where switching is allowed and not dimming/scene control: • Spaces with one luminaire rated at <100W • Spaces with LPD <0.6W/sqft • Hallways, lobbies, MEP rooms • Spaces that have automatic daylight responsive controls

Page 75: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Response Requirement

• C405.2.3 – Daylight harvesting required:

• Spaces with >150W general lighting within daylight zone – Exceptions: healthcare, dwelling/sleeping units, food/drink consuming

areas, shops and stores. – Exception: area of fenestration is <24sqft – Exception: distance from fenestration to nearest obstruction is shorter than

the distance from the bottom of the fenestration to the top of the obstruction

– The daylight harvesting controls must be: • readily accessible • capable of calibration within the space they are affecting

Page 76: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Daylight Responsive Control

• C405.2.3

– Two types of daylight zones

• Toplight and Sidelight – Must be controlled independently

– Separate zones must be created if lights are facing <45 degrees from a different cardinal direction and >150W

Page 77: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Hotel/Motel Requirement

• C405.2.4

– Hotel and motel sleeping units:

• Requires a master controller to shut off all lights and receptacles within 20 minutes upon leaving the space

Page 78: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Exterior Lighting Requirement

• C405.2.5 – External photo sensor to shut off lights based on available

ambient light

– Time clock control based on dawn/dusk and open/closing time • If not acceptable:

– Must automatically reduce lighting power >30% from:

» 12am-6am or,

» 1hr after closing – 1hr before opening or,

» No activity for >15m

– Exception: covered vehicle entrances/exits, security areas

Page 79: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Additional Efficiency Requirement

• C406.1 – All buildings must choose one:

• More efficient HVAC (C406.2)

• Reduced LPD (C406.3)

• Digitally addressable networked lighting control system (C406.4)

• One-site supply of renewable energy (C406.5)

• Dedicated outdoor air system for HVAC equipment (C406.6)

• High efficiency service water heating (C406.7)

Page 80: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Additional Efficiency Requirement cont.

• C406.4 – Digitally addressable lighting system details:

• Continuous dimming

• Individually addressable

• Daylight zone

• Digital reconfiguration available

• Load shedding

• Individual user control

• Reconfiguration of occupancy sensors available

Page 81: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Why the increase in Energy Efficiency?

Net Zero Energy Buildings & Architecture 2030

Architecture 2030’s mission is to create, and quickly respond to, opportunities that shape the dialogue and address the crisis situation surrounding the ‘Building Sector’ and its contribution to global warming.

The goal is for every building to be carbon neutral by the year 2030

Net Zero

1990 2030 2010 1980 2000 2020

Page 82: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Architecture 2030 goals

30%... in 2010 be 30% below the 1999 Standard

5%... every 3 years after 2015 be an additional 5% less than the 1999 Standard until the year 2030

50%... in 2015 be 50% below the 1999 Standard Buildings represent 76% of U.S.

Electricity Generation

1990 2030 2010 1980 2000 2020

Net Zero

100% Carbon Neutral = 0% Fossil Fuels

Page 83: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

How are we going to reach 2030 goals?...

Can we continue to lower the W/ft2 through lamp technology alone?...

1990 2030 2010 1980 2000 2020

Net Zero

Can we continue to lower recommended foot candle levels?...

Can we design smarter buildings?...

Page 84: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

A Global Presence

59 Offices, 90 Countries, 2500+ Employees, 300+ Engineers, Training Centers, 24/7/365 Support

Integrated Building

Technology

Page 85: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Primary Building Energy Components

HVAC Water

Lighting

Building Envelope

Page 86: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Computers, Printers, Copiers Smart Appliances Audio/Video Equipment Keypads, Touchpanels, OC, PC Ceiling Fans, Space Heaters Security Cameras & Card Readers Motorized External Louvers Motorized Shades Internet & Exchange Servers Room Partitioning Systems Other Plug Loads

Secondary Building Energy Components

Page 87: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Photovoltaics Water

Wind

Geothermal Heat

Renewable Building Energy Components

Page 88: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

The Goal…

Smarter Design & Control Strategies

Higher Efficiency Primary & Secondary

Systems

On & Off-site Renewable Energy Systems

Utilizing efficient building systems helps lower overall building W/ft2

Replacing utility power with renewable energy helps lower building W/ft2 further

Incorporating integrated building control strategies helps lower W/ft2 even further!

Page 89: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

A Global Presence

59 Offices, 90 Countries, 2500+ Employees, 300+ Engineers, Training Centers, 24/7/365 Support

Benefits of a Single

Platform and IBT

Solution

Page 90: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

The face of Energy Monitoring is changing…

Page 91: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

We’re not just gathering energy data anymore. We’re analyzing it, we’re integrating it with other building systems,

and we’re required to save more energy than ever before!

The face of Energy Monitoring is changing…WHY?

Page 92: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Data in…

Control out!

Page 93: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of a single platform solution…

Centralized Control

A single location for facility managers to conveniently view and manage lighting, shades, occupancy status, current temperature, and alarms for individual rooms, floors, and buildings

A single location for facility managers to remotely access pre-programmed system touch screens

Page 94: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of a single platform solution…

Centralized Control

Scheduling & Automation

A single location for programming lighting, shade, & hvac automation rules tied to scheduled meetings and events

A centralized energy management control system that integrates seamlessly with corporate scheduling software such as Microsoft Outlook or Lotus Notes for an added layer of energy savings capability

A single location tied to an astronomical timeclock where facility managers can modify and create newly scheduled events

Page 95: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of a single platform solution…

Centralized Control

Scheduling & Automation

A single location for gathering real-time energy data of true power consumption & power factor

Monitoring & Reporting

A single platform to not only monitor & report energy consumption from electricity, but also from natural gas, steam, petroleum and other energy categories as needed

A single location for gathering feedback information from lamp and ballast failures as well as room status

Page 96: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of a single platform solution…

Centralized Control

Scheduling & Automation

Monitoring & Reporting

A single location to view, trigger and instantly reduce energy consumption when desired by an owner or when requested by a utility company

Demand Response & Load Shedding

A single location to program & change load shedding rules

Page 97: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Benefits of a single platform solution…

Centralized Control

Scheduling & Automation

Monitoring & Reporting

Demand Response & Load Shedding

A single platform to coordinate occupancy and daylight sensing controls with lighting fixtures, shades, and hvac equipment for truly enhanced energy savings

Lighting, Daylighting & HVAC Control

Page 98: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

A Global Presence

59 Offices, 90 Countries, 2500+ Employees, 300+ Engineers, Training Centers, 24/7/365 Support

Integrated Building

Technology

Example

Page 99: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Every system working together.

AV Control

Lighting

HVAC & Climate Control

Energy Mgt

Security

Drape/Screen

Remote Mgt

The IBT Solution

Page 100: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

The President of a fortune 500 company schedules an 9:00am meeting, in the summer, to be held in the conference room and wants to present a power point

The meeting is cancelled at the last minute, but the IT department is not notified. The lights & projector remain on for the rest of the day. The blinds remained closed. The HVAC system continues to cool an unoccupied room. Other employees would like to use the conference room later on in the day, but go elsewhere because they are not sure if there is a meeting about to begin in the conference room or not.

Non-Integrated Example

• He sends out meeting invite via Outlook Calendar

• Emails IT department to prepare the room which includes: setting up & turning on the projector, manually closing the blinds, adjusting the thermostat to pre-cool the room down to prepare for a large group of people, and turning the lights on

Page 101: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

The President of a fortune 500 company schedules an 9:00am meeting, in the summer, to be held in the conference room and wants to present a power point

Integrated Example

• Sends out meeting invite via Outlook Calendar

The meeting is cancelled at the last minute. At 9:10am the room’s occupancy sensor senses no presence & sends a signal to the building’s Energy Management System which automatically turns the lights & projector off, the motorized blackout shades open, the hvac system stops cooling and returns to an un-occupied set point temperature, and the Outlook integrated touch screen next to the door indicates the room is ‘Open’ and others may use it

• 5 minutes before the meeting is to begin, the room automates to a pre-programmed ‘AV Presentation’ preset. The lights go to a preset scene, the projector warms up, the blackout shades close, and the room pre-cools itself down to a pre-determined set point temperature for an occupied space

Page 102: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Buildings perform better. Buildings save energy.

IBT Benefits

Page 103: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

Can we select efficient individual building energy systems?…

Can we make it easy for the facility manager to use and continue to save energy?...

Can we design more efficient buildings than ever before?...

The new design questions…

Can we integrate control of these individual systems to together to save even more energy?...

When do we start?...

Page 104: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating

This concludes the 1 hour Crestron AIA Continuing Education Seminar on: CRES11: Energy Codes & Integrated Building Technology

Thank You. Please feel free to complete the course evaluation forms.

Page 105: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating
Page 106: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating
Page 107: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating
Page 108: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating
Page 109: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating
Page 110: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating
Page 111: CRES23: Daylight Harvesting & Controls...Daylight Concerns: • Sky Factor • Building Orientation 17 South-facing windows are most advantageous for daylighting and for moderating