Have used this excellent site for research, but this is my first post.
I have a room with one outside wall, and on this wall is a chimney breast which has been closed in the past, but no air brick. I removed the hearth entirely as the builders laid the toes of the floorboards onto the brick surround which didn't have a DPC. Well it did if you consider the floorboards were nailed down onto roofing felt!!
I have removed the hearth and there is now a void from underfloor, up the chimney breast, to an air brick whichis roughly between the my property and the upstairs flat. Also the chimney stack is removed and is capped, but I can't see form ground level if there is a vent.
My question is, should I fit a vent and grill in the room above the skirting to allow airflow as condensation gathers on the face of the chimney breast?