I'm trying out Sweet Home 3D but I couldn't figure out how to draw a wall that is not rectangular in shape, like this:



At first I thought I could just draw two segments with different thicknesses, but of course then I get this:



In other words, the middles of the walls are aligned, not the insides.

And for something like this the approach with two segments doesn't work at all:



In this case I thought I could draw the wall as a polyline, but when I tried it the magnetism doesn't work and I can't even get the polyline to close.