Intent:
- Provide connection between indoor and outdoor spaces through introduction of daylight and views into regularly occupied areas of the building.
Implementation:
- OPTION 1 – GLAZING FACTOR CALCULATION
- achieve min. 2% glazing factor in minimum of 75% of regularly occupied areas.
- OPTION 2 – DAYLIGHT SIMULATION MODEL
- through computer simulation, demonstrate min. daylight illumination level of 25 footcandles in min. of 75% of regularly occupied areas.
- OPTION 3 – DAYLIGHT MEASUREMENT
- through records of indoor light measurements, demonstrate daylight illumination level of 25 footcandles in min. of 75% of regularly occupied areas.
- ALL CASES
- only area associated with room (actual square footage) can be applied toward the 75% total area calculation
- provide daylight redirection and/or glare control devices
Code:
- none
Extra Credit:
- Provide daylighting for 95% (instead of 75%) of occupied areas.
Submittal Phase:
- design
Indoor Environmental Air Quality
- EQ P1 – Minimum IAQ Performance (prerequisite)
- EQ P2 – Environmental Tobacco Smoke (ETS) Control (prerequisite)
- EQ 1 – Outdoor Air Delivery Monitoring
- EQ 2 – Increased Ventilation
- EQ 3.1 – Construction IAQ Management Plan, During Construction
- EQ 3.2 – Construction IAQ Management Plan, Before Occupancy
- EQ 4.1 – Low-Emitting Materials, Adhesives & Sealants
- EQ 4.2 – Low-Emitting Materials, Paint & Coatings
- EQ 4.3 – Low-Emitting Materials, Carpet Systems
- EQ 4.4 – Low-Emitting Materials, Composite Wood & Agrifiber Products
- EQ 5 – Indoor Chemical & Pollutant Source Control
- EQ 6.1 – Controllability of Systems, Lighting
- EQ 6.2 – Controllability of Systems, Thermal Comfort
- EQ 7.1 – Thermal Comfort, Design
- EQ 7.2 – Thermal Comfort, Verification
- EQ 8.1 -Daylight & Views, Daylight 75% of Spaces
- EQ 8.2 – Daylight & Views, Views for 90% of Spaces
33 Comments On This Post
For Implementation 1, it should be “2% Daylight Factor”, not “Glazing Factor”. Great web site. Very helpful – Bur I don’t think it get me to pass the exam tomorrow, but helpful none the less. I’ll just keep trying until I get it.
I need some clarification, on my flashcard notes I have strategies to consider: light shelves, exterior fins, louvres, and adjustable blinds, among others, but these were mentioned someplace else, in the Calc Method (option 3) that those technologies are not included…,
I am further a little confused about Glare Control, they make a big deal about it, isn’t required? how can you successfully use the Calc Method if it doesn’t include glare control like light shelves, louvres etc…
option 3: compliance by measurement…the credit has to be submited as design submital.How is it posible to measure the day light when the project is in design stage?
Software like AGI32 by Lighting Analysts, or Autodesk VIZ, maybe Revit too now, and some others, can do 3D daylight modeling.
Mike-
The “2% Glazing Factor” is correct according to the Ref Guide. It says, “Achieve a minimum glazing factor of 2%…”
Valeria-
Those strategies are for all 3 methods. The guide says “In all cases…” Some are daylight redirection tools (light shelves, fins, louvers, etc) and others are glare control tools (blinds, shades, etc). The requirement is to “avoid high contrast situations” by using one or both types of devices if necessary. If you are going to use the calc method then you would want to include all of your daylight redirection tools as this will have a dramatic effect on you daylight penetration and levels. These are typically architectural features and not controlled by the occupant whereas glare control devices are and therefore harder to model.
Ahamed-
You bring up a great point. It’s obvious that its meant to be actual measurements and not simulation measurements because there is another option of simulation models looking for the same information. It’s kind of hard to do actual measurements if this is a design phase submittal. I suspect that there would be some allowance made for this when you note that choice on the template form and follow up with the data during the construction phase.
Ahamed
Possibly Option 3 is calculated through physical model instead of computer model (option 2) to asses fc level.
Okay this is a stupid question but I’m asking anyway.
I was assuming “shallow floor plates” as a strategy in Daylighting & Views was referring to low floor-to-floor heights, which doesn’t make a lot of sense. It has just occurred to me that they actually mean *narrow* floor plates, i.e. shallow from wall to wall, not floor to floor.
Am I right?
@Melissa,
No, i believe the correct term is a “shallow floor plate” I was trying to find a good definition of what this exactly means, but the only thing I could find that proved this is the correct term comes from a number of websites for daylighting and ventilation strategies. Please see the following excerpt:
“The new Weber + Thompson headquarters will include other green features. The design emphasizes daylighting with a shallow floor plate that allows light to penetrate from both the exterior and the open-air courtyard. All workstations will be located near windows to take advantage of the natural light, improving the quality of the working environment and reducing the need for artificial lighting and, by extension, energy consumption.”
Hope this clarifies things a little!
Thanks! I wasn’t exactly asking whether they or I was using the correct term–just whether (as you’ve confirmed) “shallow floor plate” means that the distance between glazed walls is relatively low.
Please explain Glazing. There seems to be several definitions. Is it the window or clear illumination area or is it a type of window or type of film on a window.
Thanks,
Please explain Glazing. There seems to be several definitions. Is it the window or clear illumination area or is it a type of window or type of film on a window.
Thanks, Added email follow up to question.
From the Leed Prep Test:
Which of the following statements is not true of light shelf design?
A Building latitude determines the depth of the overhang
B Can be a roof surface
C Provides an ideal shelf for building vegetation
D Creates daylight glazing areas on windows
Answer is C but how can B be correct!
Any input would be appreciated.
Taking the exam in a week and this one stumped me.
Thanks
Steve
Steve,
A properly positioned roof surface could behave like a light shelf. Rare, but a possibility nevertheless.
Steve or Lisa
How can D be correct? How does a light shelf ‘create’daylight glazing areas on windows? Windows ARE glazing and create daylight areas . . .
Can you explain?
Jessie –
I believe that EQ c8.1 destinguishes two different types of glazing: vision glazing and daylight glazing. Vision glazing is the part of the window area that produces daylight to the workstations closest to the windows; daylight glazings, in the contrary, allows daylight to penetrate deeper in the building.
Window area that is higher than 7’6” is automatically considered “daylight glazing” (per LEED ref guide, pg 375, option 1, bullet 2), because its height allows daylight to go deeper inside the space; however, by using a light shelf, ie a reflective surface that will direct daylight towards the ceiling and allow it to penetrate deeper inside the space, you can transform a window area that would otherwise be considered ‘vision glazing’, into a ‘daylight glazing’ window area. For a more visual visual description of my explanation, see fig.1 on pg 374 of the ref guide.
C is the correct answer – by elimination
Steve,
B is true because you could potentially have anadjacent roof at a lower height than the window that is allowing the light in thus reflecting light on the ceiling of the space.
Can anyone help explaining two sample questions
Q12 answer is A. Why not C?
Q 25 answer is C, D & F. Why C but not E?
Q 12 The design for a labontoq includes numerous fume hoods-a potentially energy-intensive ventilation system.However, the number o€ hoods operated at any one time will be highly variable. The engineer has thereforeproposed a novel demand-based system that will vary the building vendation outside-air supply and exhaust rates depending on hour many fume hoods are in use. The engineer has predicted that this one strategy alone will save approximately 50% of fan energy, which accounts for 40% of the budget design energy cost. Thus the demandcontrolled ventilation alone might save as much as 20% of the overall building energy cost.
To which LEED Credits, and by what method of assessment and documentation, might energy savings from demand-controlled ventilation (i.e., variable rate ventilation) contribute?
A) EA Credit 1, Optimize energy performance, via modified operation schedules described in the submittal
B) ID Credit 1, Innovation in design (using a suitable calculation method for the novel design approach
C) ID Credit 1 and EA Credit 1, based on documentation of both innovative design and energy savings
Q 25. Where applicable, building geometry that effectively shadcs fenestration is desirable because it facilitates which three of the following? (Choose three.)
A. use of darker glazing with a lower SHGC to prevent excess solar gain from entering the building
B; more insulative glazing to prevent loss of heat in the winter
C, more nearly dear glazing as means of allowing more dayhght to enter the building
D more nearly dear glazing as means of a allowing potentially desirable winter solar gain to enter the
building, while blocking undesirable summer solar gain
E. simpler, and thus more cost-effective, daylight-sensing controls for electric lighting reduction of glare and themla1 discomfort for occupants adjacent to glazing
Athena
1. Not C becuase you cannot get an innovation point for a technology that is already getting you an ordinary credit.
2. Not E becasue the daylight control system would be the same regardless. What is answer F? its missing.
Can not get the Glazing Factor Equation to work? Do we need it for the exam?
Something is wrong with the equation 1 or glazing factor tabulation spreadsheet (table 2) in EQ8.1, any idea what?
Most factors in equation 1 are less than 1.0, wdw. area/fl.area in most cases will be less than 1.0, so to get glazing factor bigger than 1.0 will be difficult.
How come they have glazing factor = 3.3 in tabulation spreadsheet (table 2) in EQ8.1?
Any idea anyone?
thanks
I hope that someone will explain the formula for us. Thanks for asking your question as I, too, am having problems understanding the glazing factor calculation on page 379.
Thanks,
I too am wondering what option ‘F’ was for Athena’s Q 25 because otherwise I would have chosen C, D, E.
Regarding 8.1 equation:
GF = WA/OFA * WGF * ATV/MTV * WHF
This is all commutative, so doesn’t matter which is multiplied/divided when.
So for Table 2 data row 3 (first ROS ID 103):
Window 1 has sidelight vision glazing, so:
330/2250 * .1 * .9/.4 * .8 = .0264
Window 2 has sidelight daylight glazing, so:
110/2250 * .1 * .7/.7 * 1.4 = .0068
Then, adding the two: .0264 + .0068 = .0332.
Make that a rounded percentage and you get 3.3 %
That’s how I arrived at the answer, anyway …
Jessie and Athena
is not c because they said the building will save 20% of total energy cost, you need 45.5% to get the id point. If I am not right please someone let me know.
Thanks
Can someone explain what “auto photocell-based control” is? “auto photocell-based control” is one of the strategies for EQC8.1.
And I am wondering why (B) can’t be the answer to the following question from LEED NC Sample Exam. Isn’t “auto photocell-based control” something similar to “photoelectric daylight sensors”? The book says the answer is (A). I have objection against (A) but isn’t (B) also an answer?
Question : Plans for a high-performance 80,000 sq ft laboratory include the use of photoelectric daylight sensors. Which LEED-NC credit will the sensors contribute toward?
(A) EAC1, Optimize Energy Performance
(B) EQC8, Daylight and Views
(C) SSC8, Light Pollution Reduction
(D) EAC2, On-site Renewable Energy
Thanks.
Because the primary intent of EQC8 Daylight and Views is to “provide a connection between indoors spaces and the outdoor environment thru the introduction of daylight…” This is mainly geared to long-term occupant comfort.
Photocells are a means of reducing power consumption, or “optimizing energy performance”, and thus EAC1 is the most relevant point.
An auto photocell-based control is a light sensor that only allows lighting fixtures located near windows or skylights to turn on when daylight levels fall below minimum levels.
Pat
thanks for the excellent site! i am using it to study for the LEED NC exam this saturday. i have come across many questions on sample tests about building orientation. where can this information be found, and could you please sum it up?
thanks!
Two questions I came across in the LEEDExcel practice test Can anyone clarify?
Q: What is the best practice for glare control for EQ Credit 8.1 Daylight and Views for sidelighting with daylight glazing? (Choose 1)
A Fixed interior
B Exterior Shading Devices
C Interior fins
D Louvers
E Adjustable blinds
Correct answer is E
Q: Which of the following might best contribute to EQ Credit 8.1 Daylight and Views? (Choose 4)
A Permanent shading devices
B Building orientation
C Decreased building perimeter
D High performance glazing
E Placement of offices around perimeter
F Shallow floor plates
Correct answers A, B, D, E
Focusing on shades, these answers seem to contradict one another. In one adjustable shading is good and fixed is bad. In the other fixed seems to contribute.
Anyone help–test is tomorrow!!!
I need some clarification:
Is glazing factor the same as daylight factor?
> Is glazing factor the same as daylight factor?
Although the glazing factor does not include a sky model, in practical use it is similar to the daylight factor since it is likewise independent of building orientation and prevailing climate. Thus, measures of daylight obtained using these methods cannot be reconciled with, say, the results of a solar shading evaluation since the methods employ essentially incompatible bases.
On related matters, for a critique of the clear sky option of LEED 2.2, see section 3.3 (pages 11-13) of this CIE document:
http://www.cie.co.at/div3/docs/mardaljevic-cie-rs.pdf
-John Mardaljevic
A spreadsheet indicating glare control is implicitly mentioned as being required in v2.2 for both options 1 & 2 of this credit. It is not mentioned in option 3 in the v2.2 book, template, or CIRs. Can any validate that glare control identification is not required with option 3?