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Knowledgebase : Simulations
DesignBuilder includes a wide set of predefined selectable outputs. However there are some situations when it may be useful to expand the default set.This can be done by including additional output variables using one of the following 2 routes (Scripting ...
It isn't possible to calculate summer design cooling loads for each hour by simply summing internal gains for that hour because it is necessary to take into account the building thermal mass, as well as the difference between convective and radiant heat t...
Glaser diagrams use the concept of "equivalent thickness of air" on the X-axis which defines the amount of resistance to moisture diffusion relative to the equivalent thickness of air. When layers are compressed together this means that they offer little ...
Building designers are increasingly being asked to assess how their buildings will perform in future climate conditions.  To help designers assess future building performance, organisations such as CIBSE and CSIRO have issued sets of ‘future weather year...
In Windows 10 and 11 machines, users must have .NET framework 2 (or 3.5 which includes 2) for Glaser diagrams to be displayed. This can be enabled from the Windows Features dialog: You may need to download and install .NET 3.5 manually from Microsoft we...
To reinstate the hidden messages and popup dialogs please go to DesignBuilder menu TOOLS > PROGRAM OPTIONs > DIALOGS tab and at INFO panel click at SHOW ALL HIDDEN MESSAGES  See image below for reference:
If you get the message "JobServer not available" then this means that the simulation service is not running. To fix this please check if the DBJOBSERVER service is running on your machine Windows Services area and restart the service. See image below fo...
Parametric simulation does not provide the grid output in DesignBuilder v5.0 and previous versions. This limitation will be addressed in the future with the new Parametric module. The workaround will be to export the graph results to text/data file. Plea...
If you see the following text in the Simulation Manager "Message" column ERROR START SCRIPT FAILED FAILED TO DOWNLOAD E+ Then the probable cause is an internet connection failure that might be caused by a firewall, antivirus or network proxy blocking ...
Components can "go missing" from database lists in DesignBuilder if certain options on the International tab of program options are selected or if components are assigned to a different Region to that selected at Site level. In this case you will usual...
This warning message is caused by selecting too much hourly or sub-hourly data. In cases where there is too much data DesignBuilder will often crash following the message. The cause is usually an annual simulation with hourly or sub-hourly results request...
It is possible to include the release of moisture through plants etc in DesignBuilder simulations using the Miscellaneous option on the Activity tab and introducing a value for the latent gain.
On the Edit screen go to the surface for which data is required and on the "Options" tab under the "Simulation Output Options" header check the "Store surface output" check box and then the "Solar Incident" check box. This will ensure that this data is ge...
It may not be immediately clear why there are heat gains through partition/floor/ceiling surfaces when they have been defined as adiabatic, i.e. no heat transfer. The reason is that the adiabatic boundary is on the outside of the surface and so heat can s...
The error message: "Error reading EnergyPlus results file - possible invalid file or 'out of virtual memory' error" may be caused either by trying to read in an eso file generated by a simulation from a different model or if there is too much ...
The difference in air changes per hour (ac/h) between the sum of mechanical and natural ventilation and infiltration values you entered on in model data and the values reported in simulation results is caused by the method used to calculate and report ...
In the most simple heating design calculation, one might use an equation similar to:   Heat load = U x Area x (T_air_int - T_air_ext) The DesignBuilder Heating design calculations use EnergyPlus running in a steady-state mode and improve on the above ...
The usual reason for parametric analysis generating a flat line is that there is no clear data inheritance path from the building level (where the parametric changes are applied) down to the individual zones/surfaces. In particular, when using Window...
The 'No data' message can be displayed when the simulation completed successfully but no data is available for the current selection. A common reason is that the data is not available for the selected interval but is available for other intervals. For exa...
One reason for differences between DesignBuilder Version 1 DHW output and simple calculations may be down to the way DB calculates the m3/s hot water consumption used as input for E+ from the l/m2-day data provided in the interface. The m3/s value supplie...
This error message can be generated after a simulation when the Include unoccupied zones in block and building totals and averages [http://www.designbuilder.co.uk/helpv4.2/#Output_Options.htm] output option is left unchecked no zones in the model are occu...
In some cooling design and simulation results you may find that occupancy sensible gains are much lower than expected. This occurs during times when the internal temperature is very high. The reason for this is outlined below. DesignBuilder supplies Ene...
You must select Comfort Output on the Simulation calculation options dialog to generate comfort data. Also check that 'Zone environmental and comfort reports' is either set to '1-All periods' or if it is set to '2-Just occupied periods' that the zone is a...
It is possible to create very large, complex building models using DesignBuilder but you should consider what you're trying to achieve by your modelling exercise before diving in and including every detail of the building design. Otherwise you may find yo...
You can get larger text on your graph by opening the Appearance header in the Display Options data panel and setting the Font size to 'Large'.