Flat and sloped roof elements
Any building needs a roof. In Archicad, there are a few approaches to model roofs. For flat roofs, it is often more convenient to use the Slab tool, if you ignore the slight slope that an actual roof requires. In that case, you simply draw the contour and set an appropriate Composite Structure. For sloped roofs, this doesn’t work. In that case, you can use the dedicated Roof tool, which is also based on a contour but provides an additional slope angle.
Modeling a simple flat roof using a Slab
To create the flat roof above the ground floor, we can simply draw a Slab. As shown in the settings in the following figure, (1) we select the default Flat Roof Composite from the Composites > Exterior folder in the popup. Note that (2) the Reference Plane property of the roof is set at the top of the Composite, with a negative offset (-150) relative to the Home Story property (3) to comply with common detailing for roof levels in coordination with...
