What are the holes in this brick fireplace

fireplace

Does anyone know why there are two holes in this fireplace box? I had to muck with the picture to make them visible…they are circled in red.

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Best Answer

They are fresh air supplies for the firebox. Houses built in recent times are have less air infiltration to supply air for combustion in fireplaces, so the fireplaces have had to have air "piped in" to allow for proper burning.