Example - Percentage Glazing Scenarios

Workspace:  Buildings-Building/Floor/Zone Definition-Create/Edit Bldg Stories

Workspace Areas:   Active Project Model Tree - 3d view - 2d view - Create/Edit Geometry

 

WWindow Wall Ratio - Single Array

One thing that can be a bit challenging when you are creating window array configurations on your building on the Glazing tab is the Win/Wall Ratio  (WWR).  At times it may seem that the ratio is  too low, however it is important to be aware of what influences the WWR.

 

The image above is the Glazing Table for one array for a 100' x 100' building footprint that is 13' tall.  All seven columns (not including exterior shading) influence the resulting number of windows and the size of the window.  

 

So for the setting in the case above 520 ft2 (40% x (100 ft x 13 ft)) will be created on the facade.  Since values are included for all five, the only real variable is what the height of each window in the array will be.  The image below (Custom Openings Workspace) shows the result, which is that each window in the array is 6.5 ft tall.  If you check the math (10 ft wide x 6.5 ft tall x 8 windows in the array), you will find that it is equal to 520 ft2.

 

 

 

Now, if we keep the same floor plate and height size, but we enable Strip Glazing ( or set the 'Window Width' to 0 ), we see that a single strip window is created starting at the 10 ft. elevation extending between the value for the 'Window Offset From the Left' and the value for the 'Window Offset From the Right'.

 

 

 

We now have a 96 foot long window that is 5.42 feet in height, which is also equal 520 ft2.

 

The scenarios get more complex as you add more arrays (up to three total), because you need to keep in mind where the window top elevations are set for each, which ultimately determines the WWR that is possible, as well as the other variables for offsets, window width and spacing.  

 

 

WWR% Multiple Arrays

The following shows a three (3) array assembly for the same building (100' x 100' building footprint that is 13' tall) described above.  The glazing table shows the default values provided for each array within Simergy when 'Three Window Arrays' are selected from the drop down list.  If you were to start entering higher WWR% values in any of the arrays and selecting 'Preview', you would soon reach a point when you would receive a message stating something like "One or more South window(s) have not been created because the windows overlap the windows below."  The reason this appears is because based on the boundary conditions that you have set by entering values in the five columns described above you have established an upper limit of what % glazing will fit.

 

 

Let's take a closer look at the vision glazing array (Array One).  The maximum height the window can be is 4.5 feet, since the Array One Window Top Elevation is set at 7 feet and the Array Three Window Top Elevation is set at 2.5 feet.  7 ft - 2.5 ft = 4.5 ft.

 

Based on our Window Width, Gap and Offset settings the array will have eight (8) windows.  So, the maximum glazed area possible for this set of values is ~325 ft2, which is 25% of the overall wall area.  If we were to edit the glazing configuration for any of the facade orientations on this floor and we input WWR = 26%, we would receive the message described above ("windows are not able to be created"), but if we input WWR = 24%, we would not receive the message.  If we had set the Window Width to zero (0), creating a single strip window, then based on the inputs up to 416 ft2 of glazing could be created, which this case equates to 32% of the overall wall area.

 

If we wanted to increase the WWR% allowed for Array One in this scenario we could do any of the following:

Maximizing Array Sizes

When you are trying to maximize the size of different arrays to potentially represent a 100% glazed facade, there are a couple of things to consider:

 

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