Baseline building: daylight controls

Yes you must include daylighting controls in perimeter areas in the baseline models. You can model the baseline with the daylighting control system that meets the minimum requirements. The proposed is modeled as designed. There still may or may not be any savings depending on any differences in the controls.

Given the lack of guidance in 2010 (2013 is clear on what to do) you could probably do one of the following and it would be accepted.
1. The same as the Proposed.
2. Follow the guidance in Appendix C3.5 in 2010 and use SHGC x 1.0 or 1.27 depending on the climate zone as indicated in Table C3.5.
3. Follow the guidance in Appendix C3.6 in 2013 as referenced in that version of Appendix G.

Further to the comment tread above. How should presence / absence lighting control be modeled in the baseline. For v4 models what should the baseline model lighting profile look like ?  

It should be automatically modeled by the software based on the interaction of the solar radiation, VLT, orientation, and configuration of the space. The other variable is the location of the sensor, which is another question.

Some software can't model this directly and then it gets messy and difficult. In the past when claiming savings for daylighting controls projects were required to do a daylighting analysis and extrapolate the results to create a profile. I assume that you would have to do the same thing.

HI Sir,

Can you give me the simple to creating a profile from a daylighting analysis or tell me how to transfer from daylighting analysis to profiles for lighting.

Thanks

It is not simple and can't be communicated in a post like this. I also have not done this either but I have seen the results of others doing it.

This has been a particular problem with HAP. Is that the software you are using?

Thanks, Sir. I doing in IES software. IES software has features for daylighting but got trouble, when I tried to change located of Dimming sensor the results be the same. That why I need to find out the ways for combine daylighting simulation in Energy Simulation.

Another question. Example, for the huge space, like a huge office, the primary side-lighting just occupy a small part (mean just a small area nearest the windows), so do I have separate independent primary side-lighting and the rest and just simulation daylighting with dimming sensor in primary side-lighting (for both case proposed and baseline). Because so many projects I doing design team will put the dimming sensor in the center of the room and drives dimming will be dimming all lighting in this room. Can I simulation the same with the design team for both case proposed and baseline. If must be the separate independent side-lighting and the rest when doing simulation daylighting, it's so complicated. Please, give me some advice. 

Thanks so much!

To link the daylight results to the energy simulation, assign a dimming profile to the lighting gain and check the radiance box before running the simulation.

I would recommend that you contact IES-VE and ask them to help you figure out how to model it in their software. This will be more readily accepted by the reviewer and you will not be allowed to use this method if the software you are using can model it directly. You can only use a work around if the software cannot model something.

I am not sure how IES does this but in eQUEST you can designate a portion of the lighting in the space to be controlled by the daylight sensor. Then you place the sensor in reasonable proximity to the daylit zone.

I'm not following the application of 90.1 (2010) addendum to projects. The original question asked if 'Addendum Cg' is to be included (specifically daylight provision for a baseline model). The guidance here suggests yes, include the day-light controls in perimeter zones for the baseline system. However the reference guide states a comparison with ASHRAE 90.1 Appendix G (with errata only). Is the inclusion of the day-light control in the baseline model per the suggestion above taken directly from the addendum or elsewhere? Assuming it's elsewhere, can a link to that resource be posted please? 

Thanks 

The original version of 90.1-2010 was clearly subject to interpretation. It includes some statements that would lead you to model the baseline daylighting controls and it includes some statements that appear to indicate that you may not have to do so. So Addendum cg appears to have addressed those contradictions providing clarity where it was not clear.

The requirement to include these daylighting controls comes from the adopting authority, USGBC. Since these control provisions are a mandatory provision and LEED requires compliance with all the mandatory provisions directly in the credit language, that is enough clarity to indicate that they should be included in the baseline. As we see from subsequent addenda that was clearly the intent of 90.1 as well. So there is no resource to point out as this is a matter of interpretation that was undertaken by USGBC/GBCI. I am not aware that a LEED Interpretation was published on this issue.

This is a very similar situation to the requirements for modeling occupancy sensors in the baseline associated with the mandatory provision for such controls in certain space types. Enforcing the mandatory provision overrides the confusing language in Table G.3.1-5.

Thanks Marcus. Much appreciated. 

A question regarding the daylight control. Do the dimming profiles need to be equal in both building? Or may we take credit to model Proposed with continuous dimming and Baseline with just the mandatory controls as per ASHRAE 90.1 - 2010 sections  9.4.1.4 c and 9.4.1.5c (eg, 3 control steps: 100%, 70% and 35%)?

Thank you in advance!

You can model the baseline with the mandatory controls and the proposed as designed.

Hi All,

In continuation with the above posts, I have a doubt on addressing LEED review comment.

I am working in a project where daylight controls are not designed till now. And we received the preliminary design review mentioning that daylight controls have to be installed as a part of mandatory requirement.

During preliminary design submission, as an alternate approach to section 9.4.1.4 , we have modeled the baseline case with automatic daylight controls as per section 9.4.1.4 and the proposed case is modeled without any daylight controls (as designed) on a worst case basis to show compliance. However, we received a review comment to install daylight controls wherever required.

So, we would like to clarify whether our approach is correct? or any other options are available.

I request your suggestions on addressing the review comment.

Thanks,

Gopinath Vasu

LEED projects are required to implement the mandatory control in the design and install them as well. The Proposed model should reflect the design and installations as well.

Your original approach was not in compliance because you did not implement a mandatory provision.

Gopinath Vasu what happened with your project? Did the reviewer accept that you modelled it in the baseline and not proposed? Did you end up having to install automatic daylight controls? If so, for how many spaces?