Redefining windows in DD Wizard

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Hi all,

Does anyone know how to redefine windows in a model as a % window-to-wall ratio once I've already create custom window placements in the DD Wizard? I removed the custom windows and defined a percentage in Wizard Screen #6 (shown below), but my 3D viewer isn't showing these new windows. Any help would be much appreciated. Thanks!

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Kristy M. Walson, PE, LEED AP BD+C

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I had gone through the same experience.
I couldnt find any location where you can directly change the WWR.
What i did was:
1. based on wall area and WWR calculate the area of window required to
achieve that WWR.
then edit the window areas in the DD wizard which can give you
correct results.
since equest calculates results based on % WWR and not on size of windows
this approach works well for me.
however, if anyone has a better option, I would love to know that.
Thanks
Regards
Deepika

DEEPIKA KHOWAL

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Kristy,

Once you've started a custom window layout, I believe there's no going
back to defining fenestrations as a WWR in the wizard mode for a given
shell.

That said, I'd speculate that you might be able to look at a pair of
dummy .pd2 files side by side in notepad, see what lines are
added/changed within after the custom window layout dialog is engaged,
then undo those changes in the target .pd2 file... that might permit
using the WWR inputs again. I'd certainly save my work separately
before exploring this.

I'd also point out that with a WWR < 40%, you have no compelling need to
redefine your fenestration layout for a LEED/90.1 baseline, if that
happens to be what you're up to ;). Much extra discussion in the
archives, if interested.

I'd submit a small clarification as well: eQuest does indeed consider
window dimensions/locations with respect to various shading surfaces -
solar loads and daylighting control calculations are not done purely on
WWR. This does become a non-issue however when doing 90.1 baselines,
which are not self-shading nor do they have daylighting controls.

~Nick

NICK CATON, E.I.T.

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This is sort of a bizarre suggestion but if you want to get rid of custom
window inputs all you have to do is make a change on one of your previous
screens and they are gone. I know, cause I've lost them when I didn't want
to. So, go back to Screen 1 and change your building type and see if that
get's you what you want.

Carol

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Regarding Nick's clarification,

I would expect that different window sizes have different frame-to-window areas, so getting the correct size of the window is important (A small window would have a greater frame-to-window area than a large window, so assuming identical frames - assuming double pane w/ aluminum frames a small window would have a worse U-factor than a large window).

Cheers,

Alex Krickx, LEED AP

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so if I increase the frame area for strip windows to match the frame area
for small windows, will the results be same?

DEEPIKA KHOWAL

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Kristy,

I had the same idea as Carol. I suggest making some change to the zoning in pattern in Screen 2. (Then changing it back.) A warning will appear that your custom windows will be deleted, but this is exactly what you want. Changing the building type in Screen 1 may reset defaults for several other things that you don't want to change. Regardless of where you make a change to reset the windows (Screen 1 or 2), check to see if anything else got reset that you did not intend to change.

________________________________
Keith Swartz, P.E., LEED AP

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Hi Deepika,

One report that I'll look at very closely is the LV-D report. It gives you the average U-value of windows (it combines frame U-value and COG U-values and takes the area of each into account). If your window distribution is correct (i.e. 20% WWR on south, 30% on west, etc) and the LV-D reported number matches what you know your assembly U-value is (that is the frame+glass U-value) then I would guess that you are in good shape.

That's more of a check to make sure that the U-values are right. You still need to make sure that the area of windows are correct (also provided in LV-D) and that the glass area are correct (LV-H) - you could have the right U-value but wrong glass area which would mean your solar gains would be off.

Regards,
Alex

Alex Krickx, LEED AP

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