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Berkeley Lab WINDOW 7

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Last update:04/24/15 01:32 PM

Download Berkeley Lab WINDOW 7

Send feedback via email to Also as bugs and comments are submitted by testers, the will be posted on this Knowledge Base, so check here for the latest information about the program.





Uninstall previous Berkeley Lab WINDOW 5 programs, including 5.1 and any beta versions.

Locked Files with Install/De-install 
If you get this message during uninstall, click ‘Ignore’

Installation Problems 
In order to install the program with the Microsoft NT (4.0), 2000, and XP, you must be Administrator or part of the Administrators Group on your machine. To check if you are Administrator, do the following:

bullet Go to Control Panel, then "Users and Password" in Microsoft 2000, or "User Accounts" in Microsoft XP
bullet Find the current username (yours) and look in the group column. It should say: Administrators
bullet If the current username does NOT say Administrators, contact your IT department to become Administrator, or to have someone with Administrator privileges install the program on the machine.

Minimum computer requirements:

bullet Pentium class or better.
bullet At least 32 MB of random access memory (RAM). For optimal operation, 64 MB or more of RAM is preferrable.
bullet Microsoft Windows 98TM, Windows 2000TM, Windows XPTM, Windows METM, or Windows NTTM
(The program WILL NOT run with Windows 3.1TM,  Windows NT 3.51TM or Windows 95TM). 
bullet Hard disk drive with at least 40 MB of available disk space
bullet Printer supported by Microsoft Windows (serial, parallel, or shared over a network).
bullet Optics5 Note: The latest version of Optics5 that is available for download IS compatible with Berkeley Lab WINDOW 5.2


Reporting Computer System Info to LBNL for Troubleshooting


"Incompatible version of the RPC stub" Message

When the installation is started, the following error message occurs:

Error number: 0x80070725
Description: Incompatible version of the RPC stub

The error appears as the following image:

This error is caused by an incompatible version of a DLL that was installed on the system, such as Oleaut32.dll, Olepro32.dll, Asycfilt.dll, Stdole2.tlb. For example, version 3.50 of Oleaut32.dll is installed and used only by Windows XP and so causes this error if it is installed on a machine running any other operating system.


Fixing the problem depends on your operating system. Go to this InstallShield website (InstallShield is the program used by LBNL for the Berkeley Lab WINDOW5 installation) where there are various resolutions depending on the computer setup:


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Trouble Loading Optics5.dll error


If you get a message saying "Trouble Loading Optics5.dll", make sure that these two files are in C:\Program Files\ LBNL\ LBNL Shared and are registered

Click here for complete instructions about how to register the DLL files.



Berkeley Lab WINDOW 5 Input File for DOE2
Berkeley Lab WINDOW 5 can write an input file that can be used with the DOE2 simulation program. Click here for a detailed explanation of the steps.

DOE-2 Input File Notes

bullet Units: The DOE2 file that Berkeley Lab WINDOW generates is always in SI units, and can be incorporated in SI units into a complete DOE2 input file even if that file is in IP units. All the GLASS-TYPE-CODE (both BDL glass library and Berkeley Lab WINDOW 4/5/6 export data) keywords in DOE2 are assumed to be in SI units regardless of whether the BDL input units are set to English vs. Metric.

DOE-2 File -- Overall & Center-of-Glass U-values Identical
In the "Overall and Center of Glass Ig U-values" section of the DOE2 file generated by Berkeley Lab WINDOW, the Overall and Center-of-Glass values are both identical, and are both the Center-of-Glass values. The report does not contain the Overall U-value of the product. DOE2 does not need that value, as it calculates it's own U-value for every time step, so this bug does not produce inaccurate results in DOE2.


Detailed Berkeley Lab WINDOW Output

Berkeley Lab WINDOW produces an output file with details of input and output to the calculation algorithms. It can be used to determine various values of interest. This file is called W5DEBUG.DAT, and can be generated as follows:



"h" stands for film coefficient in W/m2K

"con" stands for convection
"rad" stands for radiation
"in" is interior (room side)
"out" is exterior (outside)
"hin" is the total interior film coefficient
"hout" is the total outside film coefficient
This feature is somewhat buggy, so the next time you start W5, the "Debug Output" check box will still be checked (under Preferences), but the program doesn't produce the debug file (it forgot that it is checked). To reset the Debug checkbox, uncheck the box, close the program, start the program again, and check the box. Now the program will created debug output again for that session of the program. The file keeps growing, because every calculation is added to the end. It might be good to delete or rename the file after you've extracted information, so that the file doesn't grow to large. The best way to look at it, is to always go to the end of the w5debug.dat file and start looking up.

Glazing System -- Outside to Inside Layer Convention:

The layers in the Glazing System Library are displayed from outside to inside, left to right. So Layer 1 is the layer next to the exterior boundary conditions during the calculation


Laminated Glass: 
In order to model laminated glass constructions in Berkeley Lab WINDOW5, do the following:

bullet Create the laminate in Optics5 or Optics6
bullet Save the laminate into the Optics5 User Database
bullet Import the laminate into the Berkeley Lab WINDOW Glass Library, thus making it available as a layer for creating glazing systems in the Berkeley Lab WINDOW5 Glazing System Library.

Project Databases
It is possible to make a much smaller Berkeley Lab WINDOW5 project database by saving only the records in each library that are used in the defined glazing systems and windows. It is also possible to import and export records between databases. Click here for a detailed explanation of how this feature works.

Import Glass Layers from IGDB or Optics5 User Database

bullet Import Glass Layers from the IGDB or IGDB Update


bullet Import Glass Layers from Optics5 User Database:
bullet In Berkeley Lab WINDOW5, in File/Preferences, go to the Optical Data tab, and set the second option, Optics5 User Database, to your Optics5 user database (which by default is called UserGlazing.mdb, but it can have any name with the "mdb" extension) -- you can browse to the file with the browse button (its default location is in Program Files\LBNL\LBNL Shared directory).

bullet In Berkeley Lab WINDOW, go to the Glass Library List View, click on the Import button, select the 2nd choice, "IGDB or Optics User Database" as the format, and click OK. 

If you select the 3rd choice, "Frit from IGDB or Optics User Database", and then select "Glass" in the Glazing System Library

you will get an error upon calculation, saying "Invalid specularity type"

The program will open the user database set in the File/Preferences dialog box (the name will be displayed at the top of the dialog box) and you will see the glass layers that can be imported in to the existing library.

You can select the records you want to import (use Shift Click to select contiguous records, Ctl Click to select multiple non-contiguous records, or Select All to select all records). Then click the Select button, which will import the selected records into the Glass Library.

Generating BSDF XML files

Berkeley Lab WINDOW automatically generates a BSDF XML file for glazing systems with shading systems.

However, it is also possible to generate a BSDF XML file for a "spectral" glazing system, that does not have shading systems, by following the steps below. These BSDF files can be used in Radiance.


In the File/Preferences dialog box:

Calculate the glazing system

During the calculation a small window will appear showing the steps during the matrix calculation. This is an indication the program is doing the matrix calculation that will be written into the BSDF XML file. If you do not see this, then the matrix method is not be used for the calculation and you should re-check the Preference settings.


Locating the BSDF XML file

After the calculation is completed, the BSDF XML will be located in a BSDFs sub-directory, below the folder where the Berkeley Lab WINDOW database is located.

The BSDF XML file will have the same name as the glazing system, with an XML extension, such as Double Clear Air.xml

Viewing the BSDF XML file

The BSDF XML file is a text file that can viewed with a text editor, or an XML file viewer.


Exporting Berkeley Lab WINDOW 4.1 Spectral Data Text Files from Berkeley Lab WINDOW 5

bullet Go to the Glass Library List View
bullet Select the records to export from Berkeley Lab WINDOW5 to Berkeley Lab WINDOW 4.1 spectral data file format
bullet Click on the Export button
bullet Select the radio button "Selected Records"
bullet Set Format to "Window 4"
bullet Click on the OK button
bullet The files will be saved into the directory where the Berkeley Lab WINDOW 5 database is located. The name of the files will be the same as the "Name" field in the Berkeley Lab WINDOW 5 Glass Library.
bullet Copy (using Microsoft Windows Explorer or other method) those files into the Berkeley Lab WINDOW 4.1 W4Lib\SpecDat directory (or whatever directory structure set up by the user for Berkeley Lab WINDOW 4.1).
bullet Some of the newer glass library file names are not in the old Berkeley Lab WINDOW 4.1 "8 character name, 3 character extension" format, and so will need to be renamed (in Microsoft Windows Explorer or other method) before being added to the Berkeley Lab WINDOW 4.1 Glass Library
bullet In Berkeley Lab WINDOW 4.1, go to the Glass Library
bullet Do Add, New, then type the ID number to use (keep it the same as that in Berkeley Lab WINDOW5 for consistency)
bullet Type the name of the file, exactly the same as the name of the file moved into the SpecDat directory, press the Enter key (don't enter any of the values for the glass layer).
bullet Press Esc to get out of Edit mode
bullet Add more as necessary
bullet When you have finished adding all the desired records and are no longer in Edit mode, do Update, type the record numbers to update, and Berkeley Lab WINDOW 4.1 will look for the filenames specified, and update the values based on the files it finds in the SpecDat directory, including the # if it was assigned in the Berkeley Lab WINDOW 5 database.

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UV Transmittance values reported in Berkeley Lab WINDOW

Berkeley Lab WINDOW reports three different values in the whole window report for transmittance:

bullet Tdw-K
bullet Tdw-ISO
bullet Tuv

Tuv (TUV in the Standards file) is the unweighted transmittance over the ultraviolet. Because it is unweighted by a "detector" function, TUV has no correction for the spectral sensitivity of materials to radiation damage. It doesn't even cover the spectral range in which damage occurs, just the "uv" meaning below the visible. This function is included for historical comparison purposes only, since many manufacturers used this function before corrected functions were available. It is believed to have little meaning.

Tdw-K (TKR in the Standards file) is weighted by the old Krochmann damage function which purports to correct for the sensitivity of many materials. While more meaningful than TUV, it is also included for "historical" purposes, because it was included in ISO 9050 and perhaps in CEN standards before the latest recommendations by CIE.

Tdw-ISO (TDW in the Standards file) is weighted using a function recommended in the CIE standard which also derives from the work of Krochmann, but is considered to have more general validity. We had the opportunity to harmonize with CIE when the NFRC standard was last updated and we took it.

Using EN 410 Optical Standards File with Berkeley Lab WINDOW

The prEN_410.std file that ships with Berkeley Lab WINDOW  does calculate all of the glazing system properties that can be calculated with the default optical standard (called W5_NFRC_2003.std), because these calculations are not in the EN 410 standard.

If you use the prEN_410.std file in Berkeley Lab WINDOW (set in Preferences, Optical Data tab, Standards file input:

, you will see errors for the following calculation methods:

Therefore, the following results will not be calculated when using the prEN_410.std

Color Properties Tab

Optical Data Tab

These methods are found in the W5_NFRC_2003.std file as follows

Description : ASTM E308 Color - not in NFRC 300-2003
Source Spectrum : CIE Illuminant D65 1nm.ssp
Detector Spectrum : ASTM E308 1964 X.dsp
Wavelength Set : Color 5nm.wvl
Integration Rule : Trapezoidal (Normalized, k=1.0)
Minimum Wavelength : 0.38
Maximum Wavelength : 0.78

Description : ASTM E308 Color - not in NFRC 300-2003
Source Spectrum : CIE Illuminant D65 1nm.ssp
Detector Spectrum : ASTM E308 1964 Y.dsp
Wavelength Set : Color 5nm.wvl
Integration Rule : Trapezoidal (Normalized, k=1.0)
Minimum Wavelength : 0.38
Maximum Wavelength : 0.78

Description : ASTM E308 Color - not in NFRC 300-2003
Source Spectrum : CIE Illuminant D65 1nm.ssp
Detector Spectrum : ASTM E308 1964 Z.dsp
Wavelength Set : Color 5nm.wvl
Integration Rule : Trapezoidal (Normalized, k=1.0)
Minimum Wavelength : 0.38
Maximum Wavelength : 0.78

Name : TDW
Description : NFRC 300-2003 UV Damage Weighted Transmittance based on CIE 89/3
Source Spectrum : ASTM E891 Table 1 Direct AM1_5.ssp
Detector Spectrum : UV Action (a=3.6, b=12.0)
Wavelength Set : Source
Integration Rule : Trapezoidal
Minimum Wavelength : 0.3
Maximum Wavelength : 0.7

Name : TKR
Description : Old-style Krochmann damage weighted average - not in NFRC 300-2003
Source Spectrum : ASTM E891 Table 1 Direct AM1_5.ssp
Detector Spectrum : Krochmann
Wavelength Set : Source
Integration Rule : Trapezoidal
Minimum Wavelength : 0.3
Maximum Wavelength : 0.5



Long THERM Names Crash Berkeley Lab WINDOW

THERM files imported into the Frame or Divider Library with very long names caused Berkeley Lab WINDOW to crash when they are used in the Window Library. The names can now be longer.

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Glazing System -- Only one BSDF layer allowed

Berkeley Lab WINDOW 7 only allows one layer in a glazing system to be a BSDF file -- right now the program crashes when you use 2 or more layers. In future versions, we will add error checking to prevent users from defining more than one layer as a BSDF file.

Glass Layers not imported properly from Optics User Database (W7.1.32)

Berkeley Lab WINDOW 7 will not import records from an Optics User Database properly -- the optical properties will be set to zero.

The work around is to import records from the Optics User Database into a Berkeley Lab WINDOW 6 database (using Berkeley Lab WINDOW 6), and then either import those records into a Berkeley Lab WINDOW 7 database using Berkeley Lab WINDOW 7, or just open the Berkeley Lab WINDOW 6 database in Berkeley Lab WINDOW 7, which will update the database to the Berkeley Lab WINDOW 7 structure (and then it will no longer be able to be opened by Berkeley Lab WINDOW 6).

Radiance error message that it is not installed

If you install Radiance but Berkeley Lab WINDOW does not recognize that it is installed or cannot find the Radiance program, add these three lines to your W7.ini or W7.2.ini file (depending on the version you are running).


RadianceBatchPath=/c runrad.bat



Berkeley Lab WINDOW Does Not Start Optics6

The Tools/Optics menu choice allows you to start Optics from within Berkeley Lab WINDOW. However, by default, Berkeley Lab WINDOW looks for Optics5, and does not allow you to select the Optics6.exe file, even if you browse to it. Until this behavior is more forgiving, here is how you can set the version of Optics to open from within Berkeley Lab WINDOW.

The W7.2.ini file contains a line which specifies the Optics program path. To set it to look for the Optics6 file, do the following:

Edit the W7.2.ini file using a text editor such as Notepad


which can be found in




And add this line (anywhere in the file), making sure that you specify the full path where the Optics6.exe file is found. In my case, I am running the Microsoft Windows 62-bit OS, so for me, it is found in Program Files (x86). For you, it might just be in Program Files.


OpticsPath=C:\Program Files (x86)\LBNL\Optics6\Optics6.exe


Hcin Less than Zero for CEN Boundary Conditions

If you are using CEN boundary conditions, make sure to set the Thermal Calculation standard to EN673. This can be done from File / Preferences, then going to the Thermal Calcs tab and setting the Calculation standard pulldown to "EN673".

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DO NOT MODEL Shading Systems with EN 673 Thermal Model

The EN 673 Thermal Model (set in File / Preferences / Thermal Calcs tab) cannot be used to model shading systems. The program will produce results, but they will most likely not be correct.


Berkeley Lab WINDOW5’s calculations for U-values, SHGCs, and visible transmittances will be a little different than those from Berkeley Lab WINDOW 4.1. These small differences are due to the fact that Berkeley Lab WINDOW5’s algorithms have been updated to reflect the best known practices for determining window thermal and optical properties using computer simulations. These improvements also make Berkeley Lab WINDOW5 consistent with the latest ISO and ASHRAE standards (currently in draft form) on this subject. These standards are the results of many years of work by the international community and incorporate several improvements to Berkeley Lab WINDOW 4.1’s algorithms developed a decade ago.

Specific algorithms which have changed which influence U-factor calculations:

bullet gas properties and gas mixtures have been updated
bullet an improved gap heat transfer correlation is used
bullet an improved interior film coefficient results in noticeable changes for single glazed windows with changes becoming less significant the more insulating the glazing system

SHGC and Visible Transmittance calculations are impacted by the above changes. They can also be significantly impacted by the use of a different (global not direct) solar spectral irradiance function, as recently approved by ISO TC160. This means the sun is represented by direct and diffuse solar radiation not just direct radiation. For glazings which transmit evenly across the solar spectrum (clear glass) this will not lead to a noticeable change. For glazings which transmit selectively in the solar spectrum (such as green glass or some low-e coatings), solar and/or visible properties may change by up to 0.04 or so.

Finally, as discussed in the Program’s manual, Berkeley Lab WINDOW now offers interior surface temperature maps and Condensation Resistance (CR) calculations. These are new features and calculation procedures for them are evolving with NFRC and other groups.

More Details

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