- ie: nine 32x32 baseplates laid out in a square cover the same area as four 48x48 baseplates.
- Light grey (or bley) is the normal colour for baseplates.
- There must be at least one Corridor connection, preferably at the 10-brick floor height.
- Nothing should be built on or over a four-stud border of the module except the requisite airlocks.
Within the bounds of the rules a builder is free to build whatever type of module they like. Large or small, serious or not so serious, modules can even cross themes. Castle-themed modules have been especially popular as a cross-over but adapting what might traditionally be thought of as town structures is also common in Moonbase builds. Apartment buildings, classic diners, nightclubs and other civilian structures create a vision of a real community in space.