The following problem comes along with me for some years (since I use ArchiCad for what it is developed for: 3D ) and I posted this topic in a german forum and to the german support before, unfortunately without luck.
So I like to introduce my subject here in spite of my bad english skills (and I hope that this text is still understandable for you).
In the northern parts of Germany we are used to build our exterior walls with two or more layers, burnt bricks as the outer skin. And often we use the same material for the window sills.
The following picture should give you an impression of the initial situation:
For the dimensioning of windows without a parapet (breast?) I use the dimension from the lintel to the unfinished floor, in my example 2,50 meters. The zero level of the project is the finished floor level (in my example the floor contstruction has a height of 20 centimeters).
In case of a window without a parapet I have the problem to give the right automatic dimensioning for the window height. Either the window is painted correct with the window sill shown in the elevation or the dimensioning in the floor plan is correct.
The example "A" on the left with the correct dimensioning, on the right "B" with the correct elevation :
My problem is that I am not able to position the window sill independent of the window hole. There is a possibility to increase the dimension between the window hole and the lower window frame, unfortunately this only encreases the frame height.
I used the internation window element for better understanding here, upper left the sill settings with no chance to adjust the sill position, below the window settings dialog with the changed value ("0,20 m") marked red:
The small arrows in the dialog window gives the impression of the possibility to change the distance between the lower frame and the "bottom" of the window hole, instead of that the height of the lower frame is encreased, which could be done in the frame width dialog also.
4. My "ugly workarounds"
First I separeted the dimensioning from the modell drawing by using two windows, one as an empty window with the right size and overlying a second window with frames and the sill shown in the elevations. This way it is a bit difficult to handle the dimensioning with several windows. My second workaround is to use a window with a proper parapet for a correct account in the elevations and to overwrite the measured value in the floor plans. This approach is both more comfortable and dangerous then the first solution.
I tried to change the window GDL code also, but I am to unskilled for that.
So it would be very nice to have the possibility to „stick“ the window sill under the lower window frame to get a continuous appearance in 2D and 3D for my requirements.