Dear Rabbi Simon
We are planning to rent a large house with a few families this summer. There is a chapel in the house. Are we permitted to Daven in the chapel? From what I understand, there are no crosses (Christian icons) in it.
Since the house (stately home/mansion) you are renting is available to the public as a commercial enterprise it would seem that the chapel has been deconsecrated as a place of Christian worship and is now accessible (to the guest/tenant) for any use, sacramental or secular. For this reason, if you would like to do so, there is no halakhic objection to using it for tefillah.
Enjoy your holiday.
Rabbi Rashi Simon