Walls seem to not work with Daylight

[bward]

As a test, I have a small two story box; two room on the lower level and one on the upper, see attached. I have updated the T-Vis of the glass and the reflectance of the opaque materials. I have set the project location. As you can see I have the entire South wall set as a curtain wall and am getting zero LUX. It is as if the curtain wall does not allow any light in. If I place a punched window in the solid wall it also does not transmit light either. The only way I can get light in is to physically cut a hole in the wall or roof. I am running the LEED 2009 IEQ8.1 analysis, low rez. What am I doing wrong. Also, how do I switch the legend units to FC rather than LUX. My project units are set to FC.

[rds3000 · Accepted solution]

Hello.

We have set up the tool to automatically set up the export model with the 'right' settings, but sometimes there are anomolies that lead to issues like yours.  There are a couple things that might be causing this:

1. The 3d view called "_Lighting Analysis Model View" contains all of the objects that are exported for the analysis.  In this view you can turn on or off objects that you want included.  Usually the issue is that in that view a Design Option may be turned on that has a wall blocking your windows or something.  Other issues like this may be that the Phase Filter is set to something that includes walls over the openings.

2. You may be using a material for the glazing part of the curtain wall that is not actually glass or glazing, and though you can create settings that make it look transparent in the view, that tramsparency needs to be defined in the right way for LAR to pass it on to the analysis engine.  Most of the time there is no contradiction, but some materials look different than they act.  Be sure to set up the material as glass or glazing with transparency set by RGB values in the Appearance tab per this help item:  http://help.autodesk.com/view/BUILDING_PERFORMANCE_ANALYSIS/ENU/?guid=GUID-5734F60C-2D58-4D61-B0E4-0... or use a Generic material with RGB and Transparency in the Appearance tab set properly.  Glass or Glazing is more physically accurate.

If those don't fix it, please send me the model and I'll take a look.  You can send it confidentially to LAR.Feedback@autodesk.com.

To change the legend from Lux to FC, go to the View > Properties > Analysis Display Settings, and you will see the units in the table.  Here you can also change the style and turn on or off floors.  You can also get to this dialog by selecting the analysis plane and clicking Properties > Results Display.

David

[bward]

Just before you sent your resonse I downloaded the sample project and checked out the materials. That seems to be the issue. The name of the material in our office template is called "glass" but went I click the appearance tab, there is no "Glazing" sub-category, but rather a "Generic" sub-category. In that case I would have to change both the RGB color in addition make it transparent........or pick another material that has a glazing sub-category. Either way that seems to have worked.

Thank you very much for you input. See attached.

Sincerely,

Brian Ward, RA

[scheerd]

Hey Brian.

Late response, but worth noting here anyway:

You can use either Generic materials with a Transparency setting, or glass/Glazing materials with RGB for transparency per the table in Help.  the Generic material setting is most accurate with a single surface or very thin object, and for thicker objects, the transparency is lower than actual settings, so we recommend using a Glass or Glazing material with the RGB settings method.

David