Tas 3D Modeller
Frequently Asked Questions
If you have a question about the 3D modeller, check out the frequently asked questions below. If you can’t find the answer you’re looking for, please contact support.
The error is generated when the Analysis model is created, i.e. when you enter a 3D Zones view. To do so, make sure that you have a 3D window open on the workspace. On the View menu, point to Display and click Zones. You may need to refresh the 3D Zones view after correcting for this error. On the View menu, click Refresh. Alternatively, use the keyboard shortcut, Ctrl+R.
This error has been generated due to the fact that the dimensions of your window (Height, Width and Level) do not allow it to fit within the dimensions of the designated input wall.
You must consider the height, width and level of your window, in conjunction with the floor and ceiling surface widths of the zone adjacent to the window and the height and width of the input wall.
1. Height: The height of the window itself, including any frame element.
2. Level: The position of the bottom edge of the window with respect to the floor surface (including the floor surface width and frame element). The level cannot be set to less than the floor surface width.
3. Width: The width of the window itself, including any frame element.
The zone adjacent to the window contains both a floor and ceiling surface, each with a defined thickness, or width, as it is referred to within the Edit or New Element dialog.
Suppose your floor surface width is set to 0.05m and your ceiling surface width is 0.1m. If you set your default wall height to 3m, then the useful wall height onto which you can apply a vertical window type is 3m – 0.05m – 0.1m = 2.85m.
The window is not allowed to encroach within the floor or ceiling surface widths. This means that the Level dimension cannot be set to zero if your floor surface width is non-zero (which invariably it will not be). You should instead enable the Door, rather than the Wall, radio-button or set the Level to equal the floor surface width. It also means that the sum of the Level and Height cannot be such that the top edge of the window is located within the ceiling surface width.
Therefore, the default wall height minus the ceiling surface thickness minus the level (these dimensions are set in the Edit or New Window dialog) will define the maximum allowable Height, given that the numerical value entered in the Level text-entry box incorporates the floor surface thickness.
How to check floor and ceiling surface widths
On the Building menu, click Building Elements. On the Building Elements dialog, double-click your floor surface element, e.g. Ground Floor, Upper Floor, etc. Note the width and click OK. The level set for the window must not be less than this value. Double-click the ceiling building element, e.g. Ceiling and again note the width. The sum of the level and height of the window cannot be greater than this value subtracted from the wall height.
For example consider a zone with a wall height of 3m, a floor width of 0.05m, and a ceiling width of 0.1m. If we add a vertical window here the level cannot be less than 0.05m. The sum of the level and height of the window cannot be more than 2.9m.
To make a window which extends from the top of the floor to the bottom of the ceiling use the Full Wall Height setting for the window. The window height will automatically adjust to accommodate the window between the floor and ceiling.
How to check the default wall height of the input wall
On the Building menu, click Storeys and on the Storeys dialog note the Default Wall Height. This assumes that you have not edited the wall height locally within the 2D Plan view. On the toolbar, click the Select Wall button, right-click on your input wall and on the context-menu click Height. On the Wall Heights|Ceiling dialog, verify that the “Use default wall height of current storey” checkbox is enabled.
How to check window dimensions
On the Building menu, click Windows. Double-click on a window in the list. On the Edit Window dialog you can now check the window dimensions: Width, Height and Level. You should evaluate these in union with the height of the input wall and the ceiling and floor surface widths of the adjacent zone.
To open a 3D Zones view, make sure that you have a 3D window open within the workspace and that it is selected. On the View menu point to Display and then click Zones.
A 3D Zones view will display spaces to which you have applied a zone and any bounded spaces even if unzoned. Remember to refresh the 3D Zones view, either through the View menu (click Refresh) or by using the keyboard shortcut, Ctrl+R.
Note Building Elements adjacent to unzoned areas are not exported to the Building Simulator unless they are also adjacent to a zoned space.
You will not be able to apply a construction to non-exported elements and therefore you will not be able to account for their thermophysical properties. Any heat transfer mechanisms taking place through this “unfinished” section of your building will be ignored by the calculation engine.
Incidentally, a building element between a zoned and unzoned space will be treated by the calculation engine as an adiabatic link.
You must be in a 3D Zones view in order to display shadows or export a 3D DWG file.
Make sure that you have a 3D Window selected within the workspace. On the View menu, point to Display and then click Zones. Alternatively, use the keyboard shortcut Ctrl+B or on the toolbar, click the Display selected zones button. You should now be able to display shadows; on the View menu, click Display Shadows. On the same menu, point to Export and click 3D DWG/DXF. It will no longer be greyed-out.
You must refresh the 3D Zones view. On the View menu, click Refresh. The keyboard shortcut is Ctrl+R.
You MUST check all warnings as well as removing any errors before exporting your geometry to the Building Simulator.
You cannot export your geometry to the Building Simulator if it contains errors. The fact that warnings do not preclude your exporting to the Building Simulator does not mean that they do not need your immediate attention.
You are advised to remove all errors and validate or remove warnings intermittently, from model conception through to completion.
Open a 3D Zones view and refresh it at intermediate steps. As your model develops, it will be progressively error and warning free. In so doing, you will not need to address an excessive number of errors and warnings after the geometry has been set up and you enter a 3D Zones view for the first time.
On the Window menu, click Tile (if Tabbed View is selected then you must first deselect it). If you have got open only the 2D view with the DWG file displayed, then you must open a new 2D Plan view and display an existing floor plan for an alternate elevation in order to map to your model.
On the Window menu, click New 2D Plan Window. On the View menu, click Select Floors. On the 2D Plan Filter dialog, click the floor plan you wish to use during the mapping process and click OK. Tile the windows, if needed.
If you are having problems displaying the DWG: Open the drawing file in CAD and in Model view use the Select All command or press Ctrl+A. Press Ctrl+C to copy the selection. Create a new file and press Ctrl+V to paste the selection. Make sure you paste the selection near the origin. Save as a separate file. Try importing this new file into Tas, which you should now be able to view.
You are advised to check regularly for errors and warnings throughout the development of the model.
You can open a 3D Zones view at any time, with or without any zones applied.
Tip Make sure you keep refreshing the 3D Zones view as the model develops.
An adiabatic link is created between adjacent areas partitioned by a dividing wall or by a floor or ceiling surface when only one of the two spaces is zoned.
There will be no transfer of heat whatsoever into or out of the zoned space through the interface to the unzoned space. This will affect your heating and cooling loads.
Sloping the floor surface of an internal space will create, or leave behind, a gap beneath the sloped surface. Due to the fact that the space is internal to the building, you will need to “plug” the existing gap, or void, to prevent introducing a hole within the heart of your building. If this is not done, then the internal surfaces surrounding the void will be treated as ‘exposed’. This means the heat losses for this zone will be greatly exaggerated.
You need to use two storeys in order to model an internal sloped surface. To do this, on the Building menu, click Storeys. On the Storeys dialog, click New. Create a new storey, e.g. Internal Slope Floor Surface. Click OK. Click New again to create a second storey, e.g. Internal Slope Ceiling Surface. Click OK. You can now slope the floor surface of Internal Slope Floor Surface, which can be used to represent the occupied space of the zone containing the sloped floor.
As you will have left behind a gap beneath Internal Slope Floor Surface, you will need to apply the same slope to the ceiling surface of Internal Slope Ceiling Surface and then insert Internal Slope Ceiling Surface beneath Internal Slope Floor Surface. It can be ‘inserted’ by ensuring the filler storey plan occupies the same level as the space containing the sloped floor surface.
You can use the Copy to Storey(s) feature to ensure correct wall alignment between storeys is achieved.
This is an exposed building element, not an internal element. You should identify where in your model this has been applied. In the Building Simulator make sure you apply the correct construction to this building element. When part of a wall is internal, say the bottom surface area and the remaining surface area is exposed to the external climate then the software creates and applies a new element to the exposed surface. The naming convention for such elements is -exposed.
Upper Floor is an exposed surface, i.e. it is exposed to the external climate.
Upper Floor/Ceiling is an internal surface.
Ceiling is an exposed surface (exposed to external climate).
Roof shades can only be applied to a null ceiling surface. Ensure that the New Shade dialog is not set up as a vertical shading device, which is the default option. On the New Shade dialog, click the Roof radio-button.
A roof shade is a shading device that is applied to the ceiling surface (the ceiling surface should be set to null) of an external zone adjacent to the transparent building element set to receive shade provided by the external shading device.
The shaded building element can be sloped, if needed.
To set up a null ceiling surface create a “shade storey” plan. On the Building menu, click Storeys and click New on the Storeys dialog.
Typically, the shade storey plan will be positioned directly above (i.e. parallel to) the surface set to receive shading. In this case, the floor surface of the shade storey plan should be in direct contact with the ceiling surface of the shaded building element.
After the Analysis model is created, these two surfaces will be merged to create a new building element. The new element is then used to represent the shaded glazed area. In the Building Simulator you will apply a transparent construction to the merged building element.
The shade storey should be composed entirely of nulls, including the floor and ceiling surfaces. You should apply an external zone to this space. You can then apply a roof shade to the ceiling surface of the external zone, exactly as you would apply a “roof” window type (e.g. a skylight or roof light) to a ceiling surface.
Alternatively, if you are using an external roof shade adjacent to a main entrance doorway, such that the shade is positioned above the doorway and perpendicular to the façade, then the shade storey plan will not be directly above the surface to be shaded. In this instance you should create a new shade storey adjacent to the doorway, on the same level and apply an external zone, as before.
Set all elements of the shade storey to the null building element EXCEPT for the floor surface. Create a new building element of zero width and apply it to the floor surface of the external zone. When you export your geometry to the Building Simulator, the shade floor element will be exported along with everything else. Apply to this element an arbitrary construction with a solar reflectance of 0.2.
You have both created a zone and applied it to a space which is not completely bounded, i.e. there is an exposed null surface. If you have done this intentionally (for example, this is necessary when applying an external shading device), then apply an external zone to this area.
On the Building menu, click Zones. On the Zones dialog, find the zone applied to the space to which you need to apply an external zone. Enable the External Zone checkbox and click OK to accept changes.
When you refresh your 3D Zones view, the Warning will have been removed.
Note If you have not done this intentionally then you need to identify where in your model the exposed null surface has been used.
Copy the null walls to which you have applied your external shading device to the ground storey plan. Apply an external zone to the space on the ground storey. Set the ceiling surface to null and the floor surface to a new building element with a width of zero. Name the new building element to “Outside Ground Floor Surface” or similar. The null floor surface of the upper space will no longer be exposed.
Refresh the 3D Zones view and the error will no longer be displayed.
After exporting your geometry to the Building Simulator, apply a construction to Outside Ground Floor Surface with a solar reflectance of 0.2. None of the other properties of the construction are relevant.
Yes. The Transparent checkbox in the 3D Modeller is for visual purposes only.
A Courtyard is used to create an external space in a walled-off area, for example, a courtyard or quadrangle.
Example: Draw a box and click the Select Space button on the toolbar. Click within the box in a 2D Plan view to highlight the space (it will be highlighted with red hatching).
Right-click and on the context-menu click Courtyard. Open a 3D Floors view. The floor and ceiling surfaces will have been removed, leaving behind only the bounding walls.
An External Zone is a used as a means of zoning a space open to the outside, e.g. an external zone is used to zone the null area to which you apply an external shade. After exporting your geometry to the Building Simulator, the default convection coefficient for the external zone will be “External”.
How to create an external zone: on the Analysis menu, click Zones. Choose a zone and enable the External checkbox.
To view shadows in the 3D Modeller you must be in 3D Zones view. On the View menu click Display Shadows.