Air brick, solid wall goes 33cm into the house, ground floor, concrete floor, ideas why?

[finlaand]

Final thoughts...I did perhaps the obvious, late in the day, followed the straight pipe and c8 metres later assuming it carries on, it gets to directly below a fireplace.

 

[Harry Bloomfield]

Final thoughts...I did perhaps the obvious, late in the day, followed the straight pipe and c8 metres later assuming it carries on, it gets to directly below a fireplace.

That makes some sense. It's a cold air vent, for the fire. Rather than the fire drawing it's combustion air from the room, causing the occupants to have a cold draft to their backs when facing the fire - the duct supplies air straight to the fire.

 

[Ivor Windybottom]

If you have an open fire, stove or probably even a gas fire then it needs to stay there, and remain open into the room.

(this is why I'm not a fan of living room fires!)

 

[finlaand]

Yes open fire, was looking as see no air vent below or behind it (I think just the normal backfill stuff). Anyway shame was not a cellar, my boys were looking forward to digging it up. Cheers.