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LEED v4
Core and Shell
Indoor Environmental Quality

Daylight

LEED CREDIT

CS-v4 EQc4: Daylight 1-3 points

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View the LEED v4.1 version of this credit »

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Daniel Glaser

LightStanza
Principal

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© Copyright U.S. Green Building Council, Inc. All rights reserved.

Requirements

Provide manual or automatic (with manual override) glare-control devices for all regularly occupied spaces. Select one of the following three options.

Option 1. Simulation: Spatial Daylight Autonomy (2–3 points, 1-2 points Healthcare)
Demonstrate through annual computer simulations that spatial daylight autonomy300/50% (sDA300/50%) of at least 55%, 75%, or 90% is achieved. Use regularly occupied floor area. Healthcare projects should use the perimeter area determined under EQ Credit Quality Views. Points are awarded according to Table 1.
Table 1. Points for daylit floor area: Spatial daylight autonomy

New Construction, Core and Shell, Schools, Retail, Data Centers, Warehouses & Distribution Centers, CI, Hospitality

Healthcare

sDA (for regularly occupied floor area)

Points

sDA (for perimeter floor area)

Points

55%

2

75%

1

75%

3

90%

2
AND Demonstrate through annual computer simulations that annual sunlight exposure1000,250 (ASE1000,250) of no more than 10% is achieved. Use the regularly occupied floor area that is daylit per the sDA300/50% simulations. The sDA and ASE calculation grids should be no more than 2 feet (600 millimeters) square and laid out across the regularly occupied area at a work plane height of 30 inches (760 millimeters) above finished floor (unless otherwise defined). Use an hourly time-step analysis based on typical meteorological year data, or an equivalent, for the nearest available weather station. Include any permanent interior obstructions. Movable furniture and partitions may be excluded. If the finishes in the space will not be completed, use the following default surface reflectances: 80% for ceilings, 20% for floors, and 50% for walls. Assume that the entire floor plate, except for the core, will be regularly occupied space.
Option 2. Simulation: Illuminance Calculations (1–2 points)
Demonstrate through computer modeling that illuminance levels will be between 300 lux and 3,000 lux for 9 a.m. and 3 p.m., both on a clear-sky day at the equinox, for the floor area indicated in Table 2. Use regularly occupied floor area. Healthcare projects should use the perimeter area determined under EQ Credit Quality Views.
Table 2. Points for daylit floor area: Illuminance calculation

New Construction, Core and Shell, Schools, Retail, Data Centers, Warehouses & Distribution Centers, Hospitality, CI

Healthcare

Percentage of regularly occupied floor area

Points

Percentage of perimeter floor area

Points

75%

1

75%

1

90%

2

90%

2
Calculate illuminance intensity for sun (direct component) and sky (diffuse component) for clear-sky conditions as follows:
  • Use typical meteorological year data, or an equivalent, for the nearest available weather station.
  • Select one day within 15 days of September 21 and one day within 15 days of March 21 that represent the clearest sky condition.
  • Use the average of the hourly value for the two selected days.
    • Exclude blinds or shades from the model. Include any permanent interior obstructions. Movable furniture and partitions may be excluded. Assume the following default surface reflectances if the finishes in the space will not be completed: 80% for ceilings, 20% for floors, and 50% for walls. Assume that the entire floor plate, except for the core, will be regularly occupied space.
    Option 3. Measurement (2-3 points, 1-2 points Healthcare)
    Achieve illuminance levels between 300 lux and 3,000 lux for the floor area indicated in Table 3.
    Table 3. Points for daylit floor area: Measurement

    NC, CS, Schools, Retail, Data Centers, Warehouses & Distribution Centers, Hospitality, CI

    Healthcare

    Percentage of regularly occupied floor area

    Points

    Percentage of perimeter floor area

    Points

    75

    2

    75

    1

    90

    3

    90

    2
    With furniture, fixtures, and equipment in place, measure illuminance levels as follows:
    • Measure at appropriate work plane height during any hour between 9 a.m. and 3 p.m.
    • Take one measurement in any regularly occupied month, and take a second as indicated in Table 4.
    • For spaces larger than 150 square feet (14 square meters), take measurements on a maximum 10 foot (3 meter) square grid.
    • For spaces 150 square feet (14 square meters) or smaller, take measurements on a maximum 3 foot (900 millimeters) square grid.
    Table 4. Timing of measurements for illuminance

    If first measurement is taken in …

    take second measurement in …

    January

    May-September

    February

    June-October

    March

    June-July, November-December

    April

    August-December

    May

    September-January

    June

    October-February

    July

    November-March

    August

    December-April

    September

    December-January, May-June

    October

    February-June

    November

    March-July

    December

    April-August
See all forum discussions about this credit »

What does it cost?

Cost estimates for this credit

On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.

Our tab contains overall cost guidance, notes on what “soft costs” to expect, and a strategy-by-strategy breakdown of what to consider and what it might cost, in percentage premiums, actual costs, or both.

This information is also available in a full PDF download in The Cost of LEED v4 report.

Learn more about The Cost of LEED v4 »

Frequently asked questions

Is it possible to combine Options 1 and 2 for different spaces in the same building?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

What spaces are considered regularly occupied and must be included in the calculations?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

If I’m pursuing Option 2 or 3, can I average the compliant square footage between 9 a.m. and 3 p.m. for a space and use the average as the compliant square footage?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

What daylight simulation software can I use for LEED compliance?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Can I mix and match daylight analysis methods? What if one room meets the illuminance thresholds but not the ASE limit?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

My office space will have cubicles with high partitions. Should I include those in my model?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

What types of glare control are acceptable for this credit?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Do I actually need to submit the USGBC Daylight and Quality Views calculator?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Can electrochromic glazing qualify as a glare control device?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Can I use Revit to document this credit?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)
See all forum discussions about this credit »

Addenda

7/29/2022 – Updated: 9/1/2022
Reference Guide Correction
Description of change:
Under Indoor Environmental Quality Overview, Tricky Spaces:
Add a new section as follows:
"Museums
• Exceptions to Interior Lighting, Daylight, and Quality Views are permitted. See the Further Explanation, Project Type Variations sections in Interior Lighting, Daylight, and Quality Views."

Under Interior Lighting, Further Explanation, Project Type Variations
Add a new section as follows:
"Museums
• Museum exhibit and other collection spaces may be excluded from the interior lighting requirements."

Under Daylight, Further Explanation, Project Type Variations
Add a new section as follows:
"Museums
• Museum exhibit and other collection spaces may be excluded from the daylight requirements."

Under Quality Views, Further Explanation, Project Type Variations
Add a new section as follows:
"Museums
• Museum exhibit and other collection spaces may be excluded from the views requirements."


Campus Applicable
No
Internationally Applicable:
No
8/12/2022 – Updated: 8/23/2022
Regional ACP
Description of change:
This is a Regional alternative compliance path to BD+C v4 EQc Daylight BD+C v4.1 EQc Daylight, ID+C v4 EQc Daylight and ID+C v4.1 EQc Daylight

Project must be located in a latitude of 55°N or above. (Projects located below 55°N, interested in using this pilot including those in the southern hemisphere may contact USGBC)

Perform annual computer simulations for spatial daylight autonomy 300/50% (sDA300/50%) and spatial daylight autonomy 100/50% (sDA100/50%) as defined in the European standard CEN 17037:2018 for each regularly occupied space. Healthcare projects must use each regularly occupied space located in the perimeter area determined under EQ Credit Quality Views. Additionally, calculate the average sDA values for the total regularly occupied floor area.

AND

Design the building to minimize glare and excessive daylight, considering both high and low sun angles. Meet one of the following:

  • Provide automated dynamic facade systems. If using this option, the system must be included in the sDA calculations.

  • Evaluate the regularly occupied spaces for annual daylight glare probability (DGP) as described in CEN 17037:2018. For minimum glare protection, target to not exceed 0.45 DGP for more than 5% of the occupation time of the space. Provide glare control devices for each regularly occupied space. For any regularly occupied spaces with DGP greater than 0.45 for more than 5% of the occupation time, identify how the space is designed to address glare.

  • Perform annual computer simulations for spatial daylight autonomy 3000/50% (sDA3000/50%) for each regularly occupied space. For minimum glare protection, each regularly occupied space must achieve sDA3000/50% of 0. Provide glare control devices for each regularly occupied space. Note that this approach is only available for this pilot for simplification purposes and should not be considered as a substitution of ASE. 3000 lux is very high illuminance threshold and occupants should never experience it for more than 50% of their time throughout a year. ASE is a more accurate metric than sDA to evaluate daylight excessiveness in buildings.

  • Perform annual computer simulations for annual sunlight exposure 1000,250 (ASE 1000,250) as defined in IES LM-83-12. For minimum glare protection, target ASE 1000,250 of 10% or less. Provide glare control devices for each regularly occupied space. For any regularly occupied spaces with ASE1000,250 greater than 10%, identify how the space is designed to address glare.




Points are awarded according to Table 1 (linked below).

The sDA calculation grids should be no more than 1-foot (300 millimeters) square and laid out across the regularly occupied area at a work plane height of 33.5 inches (850 millimeters) above finished floor (unless otherwise defined). The area of the grid points, within a space, should exclude a band of 19.5 inches (0.5 m) from the walls (unless otherwise specified). Use an hourly time-step analysis based on typical meteorological year data, or an equivalent, for the nearest available weather station. Include any permanent interior obstructions. Moveable furniture and partitions may be excluded.

The DGP should be calculated where the person is likely to be positioned in the space, or if multiple positions are possible, the expected worst case position, at eye height of 47.2 inches (1200 millimeters) above finished floor (unless otherwise defined) in the primary viewing direction from that position. Include shading in the analysis. Only use DGP where it is expected that the vertical illuminance is a good indicator for the glare perception.


Submittals


  • Floor plans highlighting regularly occupied spaces

  • List of compliant spaces with their annual summary values for sDA100/50% and resulting average sDA100/50% value for the total regularly occupied floor area.

  • List of compliant spaces with their annual summary values for sDA300/50% and resulting average sDA300/50% value for the total regularly occupied floor area.

  • Geometric plots from simulations

  • Narrative or output file describing daylight simulation program, simulation inputs, and weather file

  • Description of design approach to minimize glare and excessive daylight including confirmation with one of the following options selected (1) automated dynamic façade systems, (2) annual daylight glare probability (DGP), (3) sDA3000/50%, (4) annual sunlight exposure (ASE 1000,250)

  • Results of design approach to minimize glare, including calculation details (for all options except dynamic façade systems) and (as applicable):

    • Automated dynamic façade systems: description of the system(s)

    • annual daylight glare probability (DGP): list of regularly occupied spaces and resulting DGP values. For spaces with values exceeding 0.45 more than 5%, explanation of how the space is designed to address glare.

    • sDA3000/50%: List of compliant spaces with their annual summary values for sDA3000/50%

    • Annual sunlight exposure (ASE 1000,250): List of regularly occupied spaces with their annual summary values for ASE 1000,250 . For spaces with values exceeding 10%, explanation of how the space is designed to address glare.




Campus Applicable
No
Internationally Applicable:
Yes
4/6/2018 – Updated: 5/1/2018
Rating System Correction
Description of change:
Under Option 1, second paragraph under AND: update "76 millimeters" to "760 millimeters".
Campus Applicable
No
Internationally Applicable:
No
7/1/2016 – Updated: 7/15/2016
Reference Guide Correction
Description of change:
Revise Option 1, Step 2, 4th bullet with proper LM-83 section numbers (2.2.6 and 2.2.7), so reads "Include glare-control devices in the model as described in Section 2.2.6, Blinds/Shades Operation, and 2.2.7, Blinds/Shades Optical Properties."
Campus Applicable
No
Internationally Applicable:
No
7/1/2014 – Updated: 2/14/2015
Form Update
Description of change:
Under Daylight, Option 1, removed check for sDA from the criteria met column.
Campus Applicable
Yes
Internationally Applicable:
Yes
1/27/2017
LEED Interpretation
Inquiry:

Is there an alternative strategy to meet the Option 1. Simulation: spatial daylight autonomy requirements for annual sunlight exposure (ASE) if the ASE (1000,250h) threshold value exceeds 10%?

Ruling:

Yes, spaces with an ASE1000,250h score greater than 10.0% and less than 20.0% are acceptable with a narrative describing how the space is designed to address glare. Additionally, spaces with an automated dynamic façade system* OR spaces smaller than 250 square feet are exempt from the ASE requirement. The ASE value must still be calculated and reported.
Projects meeting an ASE1000,250h score less than 10.0% for the entire daylit area are eligible for an exemplary performance point.

*Automated dynamic façade systems are daylighting control devices whose position or light transmission level can be automatically changed by a control system to address sunlight penetration or perceived glare in the space. Acceptable automated dynamic façade systems include interior automated window blinds or shades; exterior automated louvers, shades, or blinds; or automatically controlled dynamic glazing. Automated methods of sunlight penetration or perceived glare control do not include manually operated interior or exterior façade shading systems; manually operated dynamic glazing; or fixed exterior overhangs, fins, shades, screens, awnings or louvers whose position on the fenestration cannot be automatically changed or adjusted. Automated dynamic façade systems are allowed to have manual override but must default back to automated operation after a predefined period of no longer than two hours. Dynamic glazing is further defined in ASHRAE Standard 90.1 and the International Energy Conservation Code (IECC).

Campus Applicable
No
Internationally Applicable:
Yes
See all forum discussions about this credit »

Documentation toolkit

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LEEDuser expert

headshot

Daniel Glaser

LightStanza
Principal

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© Copyright U.S. Green Building Council, Inc. All rights reserved.

Requirements

Provide manual or automatic (with manual override) glare-control devices for all regularly occupied spaces. Select one of the following three options.

Option 1. Simulation: Spatial Daylight Autonomy (2–3 points, 1-2 points Healthcare)
Demonstrate through annual computer simulations that spatial daylight autonomy300/50% (sDA300/50%) of at least 55%, 75%, or 90% is achieved. Use regularly occupied floor area. Healthcare projects should use the perimeter area determined under EQ Credit Quality Views. Points are awarded according to Table 1.
Table 1. Points for daylit floor area: Spatial daylight autonomy

New Construction, Core and Shell, Schools, Retail, Data Centers, Warehouses & Distribution Centers, CI, Hospitality

Healthcare

sDA (for regularly occupied floor area)

Points

sDA (for perimeter floor area)

Points

55%

2

75%

1

75%

3

90%

2
AND Demonstrate through annual computer simulations that annual sunlight exposure1000,250 (ASE1000,250) of no more than 10% is achieved. Use the regularly occupied floor area that is daylit per the sDA300/50% simulations. The sDA and ASE calculation grids should be no more than 2 feet (600 millimeters) square and laid out across the regularly occupied area at a work plane height of 30 inches (760 millimeters) above finished floor (unless otherwise defined). Use an hourly time-step analysis based on typical meteorological year data, or an equivalent, for the nearest available weather station. Include any permanent interior obstructions. Movable furniture and partitions may be excluded. If the finishes in the space will not be completed, use the following default surface reflectances: 80% for ceilings, 20% for floors, and 50% for walls. Assume that the entire floor plate, except for the core, will be regularly occupied space.
Option 2. Simulation: Illuminance Calculations (1–2 points)
Demonstrate through computer modeling that illuminance levels will be between 300 lux and 3,000 lux for 9 a.m. and 3 p.m., both on a clear-sky day at the equinox, for the floor area indicated in Table 2. Use regularly occupied floor area. Healthcare projects should use the perimeter area determined under EQ Credit Quality Views.
Table 2. Points for daylit floor area: Illuminance calculation

New Construction, Core and Shell, Schools, Retail, Data Centers, Warehouses & Distribution Centers, Hospitality, CI

Healthcare

Percentage of regularly occupied floor area

Points

Percentage of perimeter floor area

Points

75%

1

75%

1

90%

2

90%

2
Calculate illuminance intensity for sun (direct component) and sky (diffuse component) for clear-sky conditions as follows:
  • Use typical meteorological year data, or an equivalent, for the nearest available weather station.
  • Select one day within 15 days of September 21 and one day within 15 days of March 21 that represent the clearest sky condition.
  • Use the average of the hourly value for the two selected days.
    • Exclude blinds or shades from the model. Include any permanent interior obstructions. Movable furniture and partitions may be excluded. Assume the following default surface reflectances if the finishes in the space will not be completed: 80% for ceilings, 20% for floors, and 50% for walls. Assume that the entire floor plate, except for the core, will be regularly occupied space.
    Option 3. Measurement (2-3 points, 1-2 points Healthcare)
    Achieve illuminance levels between 300 lux and 3,000 lux for the floor area indicated in Table 3.
    Table 3. Points for daylit floor area: Measurement

    NC, CS, Schools, Retail, Data Centers, Warehouses & Distribution Centers, Hospitality, CI

    Healthcare

    Percentage of regularly occupied floor area

    Points

    Percentage of perimeter floor area

    Points

    75

    2

    75

    1

    90

    3

    90

    2
    With furniture, fixtures, and equipment in place, measure illuminance levels as follows:
    • Measure at appropriate work plane height during any hour between 9 a.m. and 3 p.m.
    • Take one measurement in any regularly occupied month, and take a second as indicated in Table 4.
    • For spaces larger than 150 square feet (14 square meters), take measurements on a maximum 10 foot (3 meter) square grid.
    • For spaces 150 square feet (14 square meters) or smaller, take measurements on a maximum 3 foot (900 millimeters) square grid.
    Table 4. Timing of measurements for illuminance

    If first measurement is taken in …

    take second measurement in …

    January

    May-September

    February

    June-October

    March

    June-July, November-December

    April

    August-December

    May

    September-January

    June

    October-February

    July

    November-March

    August

    December-April

    September

    December-January, May-June

    October

    February-June

    November

    March-July

    December

    April-August

Cost estimates for this credit

On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.

Our tab contains overall cost guidance, notes on what “soft costs” to expect, and a strategy-by-strategy breakdown of what to consider and what it might cost, in percentage premiums, actual costs, or both.

This information is also available in a full PDF download in The Cost of LEED v4 report.

Learn more about The Cost of LEED v4 »

Is it possible to combine Options 1 and 2 for different spaces in the same building?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

What spaces are considered regularly occupied and must be included in the calculations?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

If I’m pursuing Option 2 or 3, can I average the compliant square footage between 9 a.m. and 3 p.m. for a space and use the average as the compliant square footage?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

What daylight simulation software can I use for LEED compliance?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Can I mix and match daylight analysis methods? What if one room meets the illuminance thresholds but not the ASE limit?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

My office space will have cubicles with high partitions. Should I include those in my model?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

What types of glare control are acceptable for this credit?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Do I actually need to submit the USGBC Daylight and Quality Views calculator?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Can electrochromic glazing qualify as a glare control device?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Can I use Revit to document this credit?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)
7/29/2022 – Updated: 9/1/2022
Reference Guide Correction
Description of change:
Under Indoor Environmental Quality Overview, Tricky Spaces:
Add a new section as follows:
"Museums
• Exceptions to Interior Lighting, Daylight, and Quality Views are permitted. See the Further Explanation, Project Type Variations sections in Interior Lighting, Daylight, and Quality Views."

Under Interior Lighting, Further Explanation, Project Type Variations
Add a new section as follows:
"Museums
• Museum exhibit and other collection spaces may be excluded from the interior lighting requirements."

Under Daylight, Further Explanation, Project Type Variations
Add a new section as follows:
"Museums
• Museum exhibit and other collection spaces may be excluded from the daylight requirements."

Under Quality Views, Further Explanation, Project Type Variations
Add a new section as follows:
"Museums
• Museum exhibit and other collection spaces may be excluded from the views requirements."


Campus Applicable
No
Internationally Applicable:
No
8/12/2022 – Updated: 8/23/2022
Regional ACP
Description of change:
This is a Regional alternative compliance path to BD+C v4 EQc Daylight BD+C v4.1 EQc Daylight, ID+C v4 EQc Daylight and ID+C v4.1 EQc Daylight

Project must be located in a latitude of 55°N or above. (Projects located below 55°N, interested in using this pilot including those in the southern hemisphere may contact USGBC)

Perform annual computer simulations for spatial daylight autonomy 300/50% (sDA300/50%) and spatial daylight autonomy 100/50% (sDA100/50%) as defined in the European standard CEN 17037:2018 for each regularly occupied space. Healthcare projects must use each regularly occupied space located in the perimeter area determined under EQ Credit Quality Views. Additionally, calculate the average sDA values for the total regularly occupied floor area.

AND

Design the building to minimize glare and excessive daylight, considering both high and low sun angles. Meet one of the following:

  • Provide automated dynamic facade systems. If using this option, the system must be included in the sDA calculations.

  • Evaluate the regularly occupied spaces for annual daylight glare probability (DGP) as described in CEN 17037:2018. For minimum glare protection, target to not exceed 0.45 DGP for more than 5% of the occupation time of the space. Provide glare control devices for each regularly occupied space. For any regularly occupied spaces with DGP greater than 0.45 for more than 5% of the occupation time, identify how the space is designed to address glare.

  • Perform annual computer simulations for spatial daylight autonomy 3000/50% (sDA3000/50%) for each regularly occupied space. For minimum glare protection, each regularly occupied space must achieve sDA3000/50% of 0. Provide glare control devices for each regularly occupied space. Note that this approach is only available for this pilot for simplification purposes and should not be considered as a substitution of ASE. 3000 lux is very high illuminance threshold and occupants should never experience it for more than 50% of their time throughout a year. ASE is a more accurate metric than sDA to evaluate daylight excessiveness in buildings.

  • Perform annual computer simulations for annual sunlight exposure 1000,250 (ASE 1000,250) as defined in IES LM-83-12. For minimum glare protection, target ASE 1000,250 of 10% or less. Provide glare control devices for each regularly occupied space. For any regularly occupied spaces with ASE1000,250 greater than 10%, identify how the space is designed to address glare.




Points are awarded according to Table 1 (linked below).

The sDA calculation grids should be no more than 1-foot (300 millimeters) square and laid out across the regularly occupied area at a work plane height of 33.5 inches (850 millimeters) above finished floor (unless otherwise defined). The area of the grid points, within a space, should exclude a band of 19.5 inches (0.5 m) from the walls (unless otherwise specified). Use an hourly time-step analysis based on typical meteorological year data, or an equivalent, for the nearest available weather station. Include any permanent interior obstructions. Moveable furniture and partitions may be excluded.

The DGP should be calculated where the person is likely to be positioned in the space, or if multiple positions are possible, the expected worst case position, at eye height of 47.2 inches (1200 millimeters) above finished floor (unless otherwise defined) in the primary viewing direction from that position. Include shading in the analysis. Only use DGP where it is expected that the vertical illuminance is a good indicator for the glare perception.


Submittals


  • Floor plans highlighting regularly occupied spaces

  • List of compliant spaces with their annual summary values for sDA100/50% and resulting average sDA100/50% value for the total regularly occupied floor area.

  • List of compliant spaces with their annual summary values for sDA300/50% and resulting average sDA300/50% value for the total regularly occupied floor area.

  • Geometric plots from simulations

  • Narrative or output file describing daylight simulation program, simulation inputs, and weather file

  • Description of design approach to minimize glare and excessive daylight including confirmation with one of the following options selected (1) automated dynamic façade systems, (2) annual daylight glare probability (DGP), (3) sDA3000/50%, (4) annual sunlight exposure (ASE 1000,250)

  • Results of design approach to minimize glare, including calculation details (for all options except dynamic façade systems) and (as applicable):

    • Automated dynamic façade systems: description of the system(s)

    • annual daylight glare probability (DGP): list of regularly occupied spaces and resulting DGP values. For spaces with values exceeding 0.45 more than 5%, explanation of how the space is designed to address glare.

    • sDA3000/50%: List of compliant spaces with their annual summary values for sDA3000/50%

    • Annual sunlight exposure (ASE 1000,250): List of regularly occupied spaces with their annual summary values for ASE 1000,250 . For spaces with values exceeding 10%, explanation of how the space is designed to address glare.




Campus Applicable
No
Internationally Applicable:
Yes
4/6/2018 – Updated: 5/1/2018
Rating System Correction
Description of change:
Under Option 1, second paragraph under AND: update "76 millimeters" to "760 millimeters".
Campus Applicable
No
Internationally Applicable:
No
7/1/2016 – Updated: 7/15/2016
Reference Guide Correction
Description of change:
Revise Option 1, Step 2, 4th bullet with proper LM-83 section numbers (2.2.6 and 2.2.7), so reads "Include glare-control devices in the model as described in Section 2.2.6, Blinds/Shades Operation, and 2.2.7, Blinds/Shades Optical Properties."
Campus Applicable
No
Internationally Applicable:
No
7/1/2014 – Updated: 2/14/2015
Form Update
Description of change:
Under Daylight, Option 1, removed check for sDA from the criteria met column.
Campus Applicable
Yes
Internationally Applicable:
Yes
1/27/2017
LEED Interpretation
Inquiry:

Is there an alternative strategy to meet the Option 1. Simulation: spatial daylight autonomy requirements for annual sunlight exposure (ASE) if the ASE (1000,250h) threshold value exceeds 10%?

Ruling:

Yes, spaces with an ASE1000,250h score greater than 10.0% and less than 20.0% are acceptable with a narrative describing how the space is designed to address glare. Additionally, spaces with an automated dynamic façade system* OR spaces smaller than 250 square feet are exempt from the ASE requirement. The ASE value must still be calculated and reported.
Projects meeting an ASE1000,250h score less than 10.0% for the entire daylit area are eligible for an exemplary performance point.

*Automated dynamic façade systems are daylighting control devices whose position or light transmission level can be automatically changed by a control system to address sunlight penetration or perceived glare in the space. Acceptable automated dynamic façade systems include interior automated window blinds or shades; exterior automated louvers, shades, or blinds; or automatically controlled dynamic glazing. Automated methods of sunlight penetration or perceived glare control do not include manually operated interior or exterior façade shading systems; manually operated dynamic glazing; or fixed exterior overhangs, fins, shades, screens, awnings or louvers whose position on the fenestration cannot be automatically changed or adjusted. Automated dynamic façade systems are allowed to have manual override but must default back to automated operation after a predefined period of no longer than two hours. Dynamic glazing is further defined in ASHRAE Standard 90.1 and the International Energy Conservation Code (IECC).

Campus Applicable
No
Internationally Applicable:
Yes

LEEDuser expert

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Daniel Glaser

LightStanza
Principal

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