> I wouldn’t put too much effort into vents above a door as we’ve seen that CO2 will leak through doors and even floors/ceilings very quickly.

I'd like it to vent out into the hallway and the rest of the apartment though, so not sure what you mean by it leaking through doors? It's obviously not leaking enough, hence the addition of a vent. It's either that or keeping my door open all night which isn't feasible due to noise by other family members waking up etc.