I guess I thought your original question was about balancing for a background daytime window, not just a background in a room.
When I shot film for "The Love Witch", all in hard light, this was more of an issue because (1) I had to use my light meter, and (2) with hard light, your key for the actors doesn't always hit the wall behind the actor, so the backgrounds needed separate "key" lighting on them. Also, I was following the convention of old movies of lighting the actors separately from the background. In that case, I often started out lighting the walls one-stop under key depending on what color they were painted. Since the movie was supposed to have strong colors, sometimes I put a spot on a wall that was at key exposure to make sure the color popped.
But modern movies generally aren't lit this way -- you light the space and the actor moves within that space. Sometimes, yes, you light an actor and find that the background is falling off too much and needs some extra light on it, especially in a dark-toned room like a room with dark wood panelling. Often I would just set that background light by eye though, and now with digital, by how it looks on the monitor. And you wouldn't light the room the same for day as for night, and in the scene itself, the number of practicals on or off, or whether a window shade is up or down, may be a story point, so there are no rules regarding how much light to put on a background wall.