# Roof Components - Rafters from Profile

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With the "Rafters from profile" function, rafters can be imported from the profiles attached to the respective house sides. Although the profile contains all information for the rafters, there are settings one may want to change from rafter to rafter; therefore a few configuration options are provided:

Use the selection list at the top of the dialog box to choose existing configurations. Use the disk icon to save the current configuration under the same name or a new name. Via the management icon you can create new configurations, including by adopting existing ones, modify existing configurations, or delete them. See “Save settings” in the “General Help” manual.

**Layer for rafter import (0/-2.. empty=all):** In the profile you can enter rafters in different layers. Use this field to select the layer from which rafters should be imported from the profile. This allows you to create rafters in multiple layers at once or only in a single layer.

**Positioning:** Positioning specifies which point of the rafter should be positioned:

> **Choice:** With the "Choice" option, after selecting the point where the rafter should be placed, you can graphically select the various positioning options. The program starts with one position; use the right mouse button to cycle to the next option and the left mouse button to accept the current position.
>
> **Left edge:** The left edge of the rafter, as seen from the eaves of the selected roof surface, will be positioned.
>
> **Axis:** The axis of the rafter will be positioned.
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> **Right edge:** The right edge of the rafter, as seen from the eaves of the selected roof surface, will be positioned.

**Shortening of the rafters**: Rafters can be automatically shortened during input. The shortening can be applied at the upper and/or lower rafter end. If a rafter is shortened at the upper end, it automatically receives a right-angled section. If it is shortened at the lower end, the set eaves section remains. This allows, for example, creating a blind rafter (shortened at the bottom) or the lower rafter pieces for the layer of the roof insulation.

If the option "top", "bottom" or "bottom and top" is selected here, the next appropriate fields are activated automatically.

With the additional option "from profile" the rafter setting is adopted from the profile, while the other options (top, bottom, bottom and top) override the settings from the profile.

**Reference for top shortening**: To let the program know up to where the rafters should be shortened at the top end, you can select a reference line for the upper rafter end here.

> A special case is the option "1st purlin top". With this option the program searches, starting from the top end of the rafters, for the first purlin intersected by the rafters. Primary purlins are ignored. The rafters are cut at the first purlin found.

**Distance for top shortening**: Additionally, a distance to the reference line for the rafter shortening can be entered here. A positive value shifts the cut line upward, a negative value downward.

**Reference for bottom shortening**: To let the program know up to where the rafters should be shortened at the bottom end, you can select a reference line for the lower rafter end here.

> A special case is the option "1st purlin bottom". With this option the program searches, starting from the bottom end of the rafters, for the first purlin intersected by the rafters. Primary purlins are ignored. The rafters are cut at the first purlin found from below.

**Distance for bottom shortening**: Additionally, a distance to the reference line for the rafter shortening can be entered here. A positive value shifts the cut line upward, a negative value downward.

**Consider as field boundary**: With this setting you can determine whether the rafter(s) should be considered a field boundary. This affects the splitting of a field and the tiling of the roof surface with the roof assistant. If a rafter is not to be considered a field boundary, the program will ignore it during splitting or when tiling with the roof assistant, as if it does not exist. If it is to be considered, it will bound a field during manual splitting or splitting by the roof assistant.

After configuring all values and options, you can enter the rafters using the following controls:

**Single rafter:** Rafters are placed individually. You graphically select a point on the roof. The roof surface to which the rafter should belong is determined automatically from this point. After choosing the point, the positioning is queried if you selected the "Choice" option for positioning. You can then enter an offset from the chosen point to the configured positioning edge of the rafter.

**Split field:** With the "Split field" function you can split any field (= area between 2 rafters or roof skin lines) on a roof surface with rafters. To do this, click with the mouse in the area of the roof surface to be split. The program automatically searches for the rafters that bound the area. On each side where no rafter is found, the outermost roof skin line is taken as the boundary. After confirming the field found by the program (left mouse), you enter the splitting function.

**Split 2 pts:** With the "Split 2 pts" function you can split any area between 2 points on a roof surface with rafters. To do this, select with the mouse 2 points that bound the area to be split. The first point simultaneously determines the roof surface to which the rafters should belong. After defining the field, you enter the splitting function.
