Gavin...

One suggestion...

In the room where you record, set up for a vocal track.
Test the track by singing a few bars.
Watch the meter and set the gain so that the sound registers -10 to -12 DB at peak. Try to sing in a way that maintains a fairly tight dynamic range.
Solo that track and put another meter on it and set it in record mode.

Watch the readout and see what it picks up when the room is inactive.
Go to the farthest point in the room away from the mic and softly snap your fingers to see if the needle jumps...then louder and louder.
Move around the room.

After doing that you will have a rough idea of how lively the room is and can act on it or not.

If it is lively, put an eq on the track and cut everything below 80 hertz. That will diminish some things like AC noise and computer fans.
Your mic may have a low-cut (high pass) switch that will do that also. If the low cut is helpful, it can be put on busses and the main silmilar to a limiter but for low frequency unwanted noise..

Sometimes "room noise" can be an issue of a mic being set too hot and picking up too much.


https://soundcloud.com/sunset-poet-of-texas