Replace section with that of the supplementary document.
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Credit language
© Copyright U.S. Green Building Council, Inc. All rights reserved.
Requirements
Install daylight responsive controls in 100% of the area that meets the daylight quantity thresholds above. Daylight controls must switch or dim electric lights in response to the presence or absence of daylight illumination in the space.For a minimum of 75% or more of the perimeter area used to qualify under IEQ Credit 8.2, achieve daylighting in at least the following spaces1, through 1 of the 4 options:
OPTION 1. Simulation
Demonstrate through computer simulations that 75% or more of perimeter area used to qualify under IEQ Credit 8.2 achieve daylight illuminance levels of a minimum of 10 footcandles (fc) and a maximum of 500 fc in a clear sky condition on September 21 at 9 a.m. and 3 p.m. Provide glare control devices to avoid high-contrast situations that could impede visual tasks. However, designs that incorporate view-preserving automated shades for glare control may demonstrate compliance for only the minimum 10 fc illuminance level.Option 2. Prescriptive
For sidelighting zones:- Achieve a value, calculated as the product of the visible light transmittance (VLT) and window-to-floor area ratio (WFR) between 0.150 and 0.180.
- The window area included in the calculation must be at least 30 inches (0.8 meters) above the floor.
- In section, the ceiling must not obstruct a line that extends from the window-head to a point on the floor that is located twice the height of the window-head from the exterior wall as measured perpendicular to the glass (see diagram on the next page).
- Provide glare control devices to avoid high-contrast situations that could impede visual tasks. However, designs that incorporate view-preserving automated shades for glare control may demonstrate compliance for only the minimum 0.150 value.
|
0.150 |
|
VLT |
x |
|
0.180 |
- The toplighting zone under a skylight is the outline of the opening beneath the skylight, plus in each direction the lesser of (see diagram below):
- 70% of the ceiling height
- 1/2 the distance to the edge of the nearest skylight
- The distance to any permanent partition that is closer than 70% of the distance between the top of the partition and the ceiling.
- Achieve skylight coverage for the applicable space (containing the toplighting zone) between 3% and 6% of the total floor area.
- The skylight must have a minimum 0.5 VLT.
- A skylight diffuser, if used, must have a measured haze value of greater than 90% when tested according to ASTM D1003.
OPTION 3. Measurement
Demonstrate through records of indoor light measurements that a minimum daylight illumination level of 10 fc and a maximum 500 fc has been achieved in at least 75% of the perimeter area used to qualify under IEQ Credit 8.2. Measurements must be taken on a 10-foot grid for all occupied spaces and recorded on building floor plans. Provide glare control devices to avoid high-contrast situations that could impede visual tasks. However, designs that incorporate view-preserving automated shades for glare control may demonstrate compliance for only the minimum 10 fc value.OPTION 4. Combination
Any of the above calculation methods may be combined to document the minimum daylight illumination in at least 75% of the perimeter area used to qualify under IEQ Credit 8.2. 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.
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Learn more about The Cost of LEED v4 »Frequently asked questions
See all forum discussions about this credit »Addenda
5/9/2011 – Updated: 12/3/2020
Reference Guide Correction
Description of change:
Campus Applicable
No
Internationally Applicable:
No
1/15/2016 – Updated: 4/7/2016
Form Update
Campus Applicable
No
Internationally Applicable:
No
5/9/2011 – Updated: 2/14/2015
Rating System Correction
Description of change:
Replace section with that of the supplementary document.
Campus Applicable
No
Internationally Applicable:
No
11/1/2011 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
In alphabetical order, add the following definition for non-regularly occupied space, "Non-regularly occupied spaces are spaces that occupants pass through, or spaces used in pursuit of focused activities for less than one hour per person per day (on average)."
Campus Applicable
No
Internationally Applicable:
No
11/1/2011 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
In alphabetical order, add the following definition for nonoccupied spaces, "Nonoccupied spaces are defined as spaces designed for equipment and machinery or storage with no human occupancy except for maintenance, repairs, and equipment retrieval."
Campus Applicable
No
Internationally Applicable:
No
10/1/2013 – Updated: 2/14/2015
Rating System Correction
Description of change:
Delete this sentence:
"Achieve a minimum of two points under IEQ Credit 8.2: Daylight and Views - Views AND"
"Achieve a minimum of two points under IEQ Credit 8.2: Daylight and Views - Views AND"
Campus Applicable
No
Internationally Applicable:
Yes
11/1/2011 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
In alphabetical order, add the following definition for occupied spaces, "Occupied Spaces are defined as enclosed spaces that can accommodate human activities. Occupied spaces are further classified as regularly occupied or non-regularly occupied spaces based on the duration of the occupancy, individual or multi-occupant based on the quantity of occupants, and densely or non-densely occupied spaces based upon the concentration of occupants in the space."
Campus Applicable
No
Internationally Applicable:
No
11/1/2011 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
Revise the definition for regularly occupied spaces to be, "Regularly occupied spaces are areas where one or more individuals normally spend time (more than one hour per person per day on average) seated or standing as they work, study, or perform other focused activities inside a building."
Campus Applicable
No
Internationally Applicable:
No
10/1/2013 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
Delete section 4: "4. Implementation. Meet the requirements of IEQ Credit 8.2, Daylight and Views - Views, for noninpatient areas prior to pursuing this credit."
Campus Applicable
No
Internationally Applicable:
Yes
10/1/2012
LEED Interpretation
Inquiry:
We would like to submit a CIR to request a streamlined approach for the daylight documentation. We have the particular condition of an identical cluster of office buildings. In spite of having the same foot print, each building will be uniquely impacted by orientation variation and specific surrounding context condition. The intent is to fully document one building showing that the amount of light increases as you move up through the floor plates. Then to proceed to document the worst case scenario of each building (ground floor) or the level that is least exposed to solar access. If the worst case scenario passes, then we infer based on our test case that the upper floors of the building will pass as well. This will help us streamline not only the documentation process for so many buildings but also the review process. Is this an acceptable documentation method for this credit?
Ruling:
The project team is requesting whether a campus credit may be pursued for IEQc8.1. Daylight and Views: Daylight through a typical floor plan and worst case scenario daylight calculations.Yes, the typical floor plan and worst-case scenario daylight calculations may be used for the campus credit and applied to all buildings within the master site that have identical floor plans. The 2010 Application Guide for Multiple Buildings and On-Campus Projects identifies IEQc8.1 as an individual building credit and states that each building should pursue the credit individually. However, in the same way that a multi-story building may provide a single floor plan for each grouping of identical floors, if buildings within the Master Site are identical, the same documentation may be used for each identical building. Any of the calculation methods (simulation, prescriptive, measurement) may be used. Documentation for the campus credit and associated projects must demonstrate how the worst case scenario was determined and that the only difference in the buildings is the orientation on the site. The footprint, square footage and interior layout of the buildings must be identical. Applicable Internationally.
Campus Applicable
No
Internationally Applicable:
Yes
4/1/2013
LEED Interpretation
Inquiry:
The project team would like to exclude laboratory spaces from the list of regularly occupied spaces for the Daylighting and Views calculations. The laboratory spaces are separated from other building areas but efforts have been made to provide exterior views out of the lab spaces by providing fire rated windows around the lab into the surrounding hallways and drive aisle. The laboratory areas will be used solely for research and development purposes and for proprietary reasons & secrecy concerns of the areas, exterior windows have been specifically excluded from these rooms as they will be secure internal rooms being used by a very small percentage of the building occupants.
Ruling:
"The project team is requesting that laboratory spaces be excluded from the requirements for daylight and views (credits IEQc8.1 Daylight and Views: Daylight, IEQc8.2 Daylight and Views, and IEQc2.4: Daylight and Views.) for security reasons and/or due to infrequency of use.
No, the laboratory spaces may not be excluded from daylight and views. It is unacceptable to exclude spaces from the daylight and views calculations due to security reasons. Additionally, based on the information provided, the laboratory spaces may not be excluded for infrequency of use because the spaces are typically occupied for more than one hour per day. The percentage of building occupants using the space is irrelevant. The frequency of use for regularly occupied spaces was further clarified in the definition of a regularly occupied space included in the LEED Reference Guide for Green Building Design and Construction, 2009 Edition addenda dated 11/1/2011 which states that regularly occupied spaces are “areas where one or more individuals normally spend time (more than one hour per person per day on average) seated or standing as they work, study, or perform other focused activities inside a building."" Applicable Internationally."
Campus Applicable
No
Internationally Applicable:
Yes
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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Requirements
Install daylight responsive controls in 100% of the area that meets the daylight quantity thresholds above. Daylight controls must switch or dim electric lights in response to the presence or absence of daylight illumination in the space.For a minimum of 75% or more of the perimeter area used to qualify under IEQ Credit 8.2, achieve daylighting in at least the following spaces1, through 1 of the 4 options:
OPTION 1. Simulation
Demonstrate through computer simulations that 75% or more of perimeter area used to qualify under IEQ Credit 8.2 achieve daylight illuminance levels of a minimum of 10 footcandles (fc) and a maximum of 500 fc in a clear sky condition on September 21 at 9 a.m. and 3 p.m. Provide glare control devices to avoid high-contrast situations that could impede visual tasks. However, designs that incorporate view-preserving automated shades for glare control may demonstrate compliance for only the minimum 10 fc illuminance level.Option 2. Prescriptive
For sidelighting zones:- Achieve a value, calculated as the product of the visible light transmittance (VLT) and window-to-floor area ratio (WFR) between 0.150 and 0.180.
- The window area included in the calculation must be at least 30 inches (0.8 meters) above the floor.
- In section, the ceiling must not obstruct a line that extends from the window-head to a point on the floor that is located twice the height of the window-head from the exterior wall as measured perpendicular to the glass (see diagram on the next page).
- Provide glare control devices to avoid high-contrast situations that could impede visual tasks. However, designs that incorporate view-preserving automated shades for glare control may demonstrate compliance for only the minimum 0.150 value.
|
0.150 |
|
VLT |
x |
|
0.180 |
- The toplighting zone under a skylight is the outline of the opening beneath the skylight, plus in each direction the lesser of (see diagram below):
- 70% of the ceiling height
- 1/2 the distance to the edge of the nearest skylight
- The distance to any permanent partition that is closer than 70% of the distance between the top of the partition and the ceiling.
- Achieve skylight coverage for the applicable space (containing the toplighting zone) between 3% and 6% of the total floor area.
- The skylight must have a minimum 0.5 VLT.
- A skylight diffuser, if used, must have a measured haze value of greater than 90% when tested according to ASTM D1003.
