First of all, welcome to the board, Michael! Regarding your questions @nineminutenap said: First, which axis is north? Or more specifically, if I want to orient something like a solar panel so it gets the most sun, how should I align it in relation to the red & green axes? The green axis is north by default. But axes are more for modelling purposes (for axis inference and such) and in the Model info dialogue box there is a "Location" tab where you can set the north direction to something different from the global axes. Note however that this is only a Pro feature in the Windows version while it is available in the Free version for Mac (don't ask the reason). To have a workaround, you can visit Jim Foltz' website to download and install his Location ruby script (LatLong.rb or something). Start from here. @unknownuser said: Second, is there a website or book that has a collection of home design thumbrules for things like thickness of walls, size of doors, height of windows above floors, etc. that will help a beginner lay out something that looks more like a real house than something from a Dr. Seuss book? Well, I'd say that as many countries, as many standards. Why don't you just make some basic measurements in your own home or in any building to get a basic idea? In my country the minimun hight of a room is 165 cm as I remember. Wall thickness can depend on the material and structure of the building. Well, some architects around here will surely be able to give you a couple of hints though...