Modular building standard
- See Modular building standards category for a full list of standards.
A modular building standard is a set of guidelines allowing multiple builders to join models together in a larger display, usually at a public event such as a train show or Fest. Modular building standards have been created both by LEGO itself (ie. Modular Houses) and by fans (ie. Classic Castle City standard).
Each standard imposes restrictions of one kind or another to allow for connections of one MOC to another to create a seamless (or nearly seamless) whole.