Assign Shading

Overview

In the Shading Elements panel you assign a shading system from the database to windows (roller shutter, blind, awning, interior curtain, etc.). A shading system describes the solar transmittance and reflectance of the curtain as well as its installation position (outside, inside or within the pane cavity); the records are maintained in the shading database (menu Databases > Shading…).

The assignment is stored on the same sub-surface component instance as the window component. In the simulation, the shading therefore only takes effect on sub-surfaces that also have a window component assigned. Whether the curtain is operated statically or with control is determined by the shading control in the room’s usage profile (see below).

Opening the panel

Building workspace, Building button in the left toolbar, then the Shading Elements page (group of opening pages). When opened, the 3D scene switches to the false-colour mode for shading.

False-colour display and legend

The panel table (column heading Shading) groups all visible sub-surfaces by their assignment state:

Row	Colour	Meaning
Unused shading (not connected/assigned)	Dark grey	Sub-surfaces without a sub-surface component instance
Windows without shading	Dark grey	Sub-surfaces with a component instance but without a (valid) shading system
Name of the shading system	Colour of the database element	Sub-surfaces with an assigned shading

Sub-surfaces with shading are coloured semi-transparent in the colour of the shading system in the scene. In addition, this mode colours the rooms according to whether their usage profile contains a shading control. For this, the floating scene legend (title Shading) shows two entries:

• Rooms with shading control – the assigned usage profile references a valid shading control
• Rooms without shading control – no usage profile, no or an invalid shading control

The two room colours come from the active colour scheme (light/dark). Hidden sub-surfaces are not considered in the table or colouring.

Assigning shading

The Selected surface(s) area is active as soon as at least one sub-surface is selected; the Selected shading: line shows the state of the selection (None, name and ID, %1 different components, or Component with invalid/unknown ID). Behind Assign shading two ways are available:

• DB… – opens the database dialog for selecting a shading system and assigns it to all selected sub-surfaces.
• Table – assigns the shading system highlighted in the table directly; active only with a highlighted row with a valid system and a non-empty selection.

Existing component instances of the selected sub-surfaces are updated; for sub-surfaces without an instance, a new one is created. The action can be reversed via undo.

Removing shading

Remove deletes the shading reference of all currently selected sub-surfaces. The window component and component instance remain unchanged – only the curtain is removed.

Editing, replacing, selecting

• Edit… – opens the highlighted shading system in the database dialog (also via double-click on the table row). For rows without a valid system, the double-click starts the assignment instead.
• Replace… – replaces all project-wide assignments of the highlighted shading system with another one (note dialog Replace sub-surface component). If the Windows without shading row is highlighted, all instances with a missing or invalid reference receive the newly chosen system.
• Select – selects all sub-surfaces of the highlighted table row in the scene and navigation tree.

Interaction with the shading control in the usage profile

For the NANDRAD export, a reduction factor is determined for each window from the shading system and glazing:

$$f_\mathrm{red} = \frac{g_\mathrm{tot}}{g}$$

Here $g$ is the total solar energy transmittance of the glazing and $g_\mathrm{tot}$ the total solar energy transmittance of the combination of glazing and curtain, calculated according to the simplified method of DIN EN ISO 52022-1:2018 (section 6.4.2) from the transmittance $\tau_{e,B}$, the reflectance $\rho_{e,B}$ and the installation position of the curtain, as well as $g$ and $U_g$ of the actually assigned glazing. The factor is limited to the range $[0, 1]$. Since $g_\mathrm{tot}$ depends on the glazing pairing, the same curtain becomes effective differently on different glazings.

How the factor is applied in the simulation depends on the room’s usage profile:

• With shading control: If the usage profile assigned to the room contains the shading control sub-model, a controlled shading model is created. The curtain then operates depending on the radiation sensor; the sensor orientation is automatically derived from the orientation of the façade surface on which the window sits, depending on the control category.
• Without shading control: The reduction factor acts as constant shading – the curtain is permanently active, even in winter.

Details of the calculation model created from this are described in Calculation Model: Windows.

Special case DIN 4108-2: In verification mode, the project-defined shading can be replaced by the standard specifications or ignored entirely, see Summer Thermal Protection according to DIN 4108-2.

Related topics

• Assign Window Components
• Windows, Glazing and Shading (database)
• Structure of a Usage Profile
• Calculation Model: Windows
• Calculating Shading Factors