If it’s not a funeral Mass, there is leeway as to where to celebrate:
179. The funeral liturgy outside Mass is ordinarily celebrated in the parish church, but may be celebrated in the home of the deceased, a funeral home, parlor, chapel of rest, or cemetery chapel.
The “pastoral reasons” of OCF 178.3 might indicate one of these options above. The other “reasons,” liturgical or the availability of the priest, wouldn’t automatically suggest the funeral take place outside of the church.
For you clergy out there, how often have you celebrated a funeral liturgy outside of Mass? Which of these locations have you used? Has anyone celebrated a funeral in a home?
