Excel Spreadsheet

Gabriela, For rooms with multiple windows, I normally just add up the window areas and put the total in just one row. GBCI won't question it when reviewing and it is the easiest way to go about including all windows. If your VLTxWFR is great than 0.18, LEED 2009 now requires that automated view-preserving shades be installed to control daylight. You can only choose "yes" if the project actually has these. In some cases, daylight modeling helps to show the compliant space vs. non-compliant space, because the prescriptive method does not really allow this. I only fill out the "glare control type column" if there is a "yes" in the automated shade column, or you can just write in "blinds" or whatever type of shading device the space has. Hope this helps!

Group all you windows together on an orientation that have the same characteristics, VLTand height. This will give the glazing area. The daylight zone is then established, by either twice the head height or using the 60 degree angle. That gives you the depth of the zone. This will establish your VLTxWFR. Which i bet once you combine all your window together may not be over the 0.18. Glare control is the type of shading and only check yes for automated shades when you actually have them in your project. Personally, every space used in the daylight calculations should have some type of glare control, especially if the prescriptive path is being used. The prescriptive path cannot tell you if you have any glare conditions or even when they do happen. The prescriptive path cannot show direct sun penetration. So if you just follow the requirements as noted in the prescriptive path, you won;t put blinds in a space. Not good daylight design. Even spaces on the north side of building may experience a condition where shades are needed. How can you say your space or building is well daylit when only the prescriptive path is used? You can;t.

Lauren, you should group all your windows together if they are same, but if not, that is a different zone and you should not group them together. For example, you have six windows on the south wall. All six have the same head height, but the three on the left have a sill height of 12" and the other three have a sill height of 32". Technically, that is two zones, one for each group of three. Why, because the one half the space has more glazing than the other half, and if the same VLT, could actually be overdaylit, and therefore your VLTxWFR is over the 0.18 and therefore you need shades according to the the spreadsheet, well only for half the windows. This is the stuff that I believe alot of people don;t do and it is hard for a reviewer to determine whether it has been done properly or not. I would question a space that only had one zone for the south facade and was shown two different types of windows.

Technically you would have a zone on the north and a zone on the south. The zones can overlap. If you have alot of these rooms you could just do one and then extrapulate the info. Our do what i do, and just create your own so that you can easily manipulate the spreadsheet. I'd have to see exactly what you have to help you further.

Thanks, Todd, for the tip. We haven't been questioned on this yet for a review but it is helpful to know for the future. I have been splitting up the zones if the Tvis is different, although for most projects so far the windows have been located at the same height, with same area and all, so there wasn't a need to separate them.

In my opinion, twice the head height and/or the 60 or 63 degree line are not used to establish the daylight zone. They are only used to establish the applicable window head height. After that, similar windows dictate where you draw your zone lines. If your results are outside of the 0.150 and 0.180 parameters, a second evaluation needs to be done of the zone area. You can check out the NC board for more detail on this.