Best way to model environment

Hello,

I am new to Unreal Engine, but do web development for a living, so my knowledge with development principals and concepts is not new. I am however, new to modeling, and as I said before, the unreal engine. (Aside from using it years ago to do maps for unreal tournament). My son and I have came up with a fun little exploration style game (like gone home), that just involves interacting with objects in the game and collecting them to complete objectives.

Anyway, that’s beside the point. My question is, in the concept, most of the gameplay takes place indoors. (You start out at the entrance to a kids play center, then move on to a hospital, etc). When doing these types of environments, what’s the best way to load them as ‘maps’ in-game? Would it be easiest to model each wall/floor/ non-interactive object as one large mesh and then load it in, or would making ‘snappable’ pieces and snapping them together inside of the engine to create the indoor environment be the best way to go? In my past experience, making a single model/mesh was usually preferred as it can be rendered just once on load and not have to be loaded again, but I have also seen people make the argument that if you make individual pieces and snap them together, you can render only the pieces within line of sight and save on resources.

Ideally, the entire indoor environment would be rendered as one large mesh, and all interactable objects (doors, windows, items you can pick up/look at, etc) would be rendered separately and placed in as separate game objects. This may also help when you are transition from outdoors to indoors, without having to produce a loading screen between the transition. (Although I would think rendering an entire in-door environment that is large would be extremely resource heavy).

What are your guys’ suggestions?