removing a gas fire and what chimney vent is required

[robeaton]

I plan to remove the gas fire out of my living room and brick/plaster it up. The removal of the fire and fireplace seems fairly straight forward, i am aware that i need to put in a vent or an air brick at the bottom of the chimney breast where fire was, but what do i need to do to the chimney on the roof and how much its likey to cost?

[rosebery]

As long as you ventilate the chimney at the existing fireplace there is no need to do anything else.

Cheers