I think it’s a good idea to use NFC but as mentioned by Harsha Alva and Robert Lancer NFC alone isn’t enough. We need a keypad or some other means to open the lock. There must be some bypass methods kept. I think good options to consider here are keypad, magnetic strip cards, finger print scanner or RFID tags. We could also keep a physical key.
We also need to consider one very important thing, that’s emergency situations. If there’s fire, what has to be done for evacuation.
One thought I have in mind is, if the fire alarm is triggered, the security must be relaxed. But we also need to see that this should not be misused. What are your thoughts on this?