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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Intent
To connect building occupants with the outdoors, reinforce circadian rhythms, and reduce the use of electrical lighting by introducing daylight into the space.
Requirements
Provide manual or automatic (with manual override) glare-control devices for all regularly occupied spaces. AND Select one of the following three options.
Option 1. Simulation: Spatial Daylight Autonomy and Annual Sunlight Exposure (1–3 points, 1-2 points Healthcare)
Perform annual computer simulations for spatial daylight autonomy300/50% (sDA300/50%), and annual sunlight exposure1000,250 (ASE1000,250) as defined in IES LM-83-12 for each regularly occupied space. Additionally, calculate the average sDA300/50% value for the total regularly occupied floor area. 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.Table 1. Points for Option 1
The average sDA300/50% value for the regularly occupied floor area is at least 40% | 1 point |
The average sDA300/50% value for the regularly occupied floor area is at least 55% | 2 points |
The average sDA300/50% value for the regularly occupied floor area is at least 75% | 3 points |
Each regularly occupied space achieves sDA300/50% value of at least 55% | Exemplary performance or 1 additional point if only 1 or 2 points achieved above. |
Option 2. Simulation: Illuminance Calculations (1–3 points, 1-2 points
Healthcare) Perform computer simulations for illuminance at 9 a.m. and 3 p.m. on a clear-sky day at the equinox for each regularly occupied space. Demonstrate illuminance levels are between 300 lux and 3,000 lux at both 9 a.m. and 3 p.m. Spaces with view-preserving automatic (with manual override) glare-control devices may demonstrate compliance for only the minimum 300 lux illuminance level. Points are awarded according to Table 2.Table 2. Points for Option 2
Percentage of regularly occupied floor area | Points |
---|---|
55% | 1 |
75% | 2 |
90% | 3 |
- 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.
Option 3. Measurement (1-3 points, 1-2 points Healthcare)
Measure illuminance in each regularly occupied space. Achieve illuminance levels between 300 lux and 3,000 lux. Spaces with view-preserving automatic (with manual override) glare-control devices may demonstrate compliance for only the minimum 300 lux illuminance level. Points are awarded according to Table 3.Table 3. Points for Option 3
Percentage of regularly occupied floor area | Points |
---|---|
55% at one time in the year | 1 |
75% at two times in the year | 2 |
90% at two times in the year | 3 |
- Measure at appropriate work plane height during any hour between 9 a.m. and 3 p.m.
- If pursuing one point, take one measurement in any regularly occupied month. If pursuing two points, take two measurements: 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 |
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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Intent
To connect building occupants with the outdoors, reinforce circadian rhythms, and reduce the use of electrical lighting by introducing daylight into the space.
Requirements
Provide manual or automatic (with manual override) glare-control devices for all regularly occupied spaces. AND Select one of the following three options.
Option 1. Simulation: Spatial Daylight Autonomy and Annual Sunlight Exposure (1–3 points, 1-2 points Healthcare)
Perform annual computer simulations for spatial daylight autonomy300/50% (sDA300/50%), and annual sunlight exposure1000,250 (ASE1000,250) as defined in IES LM-83-12 for each regularly occupied space. Additionally, calculate the average sDA300/50% value for the total regularly occupied floor area. 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.Table 1. Points for Option 1
The average sDA300/50% value for the regularly occupied floor area is at least 40% | 1 point |
The average sDA300/50% value for the regularly occupied floor area is at least 55% | 2 points |
The average sDA300/50% value for the regularly occupied floor area is at least 75% | 3 points |
Each regularly occupied space achieves sDA300/50% value of at least 55% | Exemplary performance or 1 additional point if only 1 or 2 points achieved above. |
Option 2. Simulation: Illuminance Calculations (1–3 points, 1-2 points
Healthcare) Perform computer simulations for illuminance at 9 a.m. and 3 p.m. on a clear-sky day at the equinox for each regularly occupied space. Demonstrate illuminance levels are between 300 lux and 3,000 lux at both 9 a.m. and 3 p.m. Spaces with view-preserving automatic (with manual override) glare-control devices may demonstrate compliance for only the minimum 300 lux illuminance level. Points are awarded according to Table 2.Table 2. Points for Option 2
Percentage of regularly occupied floor area | Points |
---|---|
55% | 1 |
75% | 2 |
90% | 3 |
- 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.
Option 3. Measurement (1-3 points, 1-2 points Healthcare)
Measure illuminance in each regularly occupied space. Achieve illuminance levels between 300 lux and 3,000 lux. Spaces with view-preserving automatic (with manual override) glare-control devices may demonstrate compliance for only the minimum 300 lux illuminance level. Points are awarded according to Table 3.Table 3. Points for Option 3
Percentage of regularly occupied floor area | Points |
---|---|
55% at one time in the year | 1 |
75% at two times in the year | 2 |
90% at two times in the year | 3 |
- Measure at appropriate work plane height during any hour between 9 a.m. and 3 p.m.
- If pursuing one point, take one measurement in any regularly occupied month. If pursuing two points, take two measurements: 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 |