Masonry chimney question

[Ctwoodtick]

My masonry chimney is in my den and the rear of chimney is in my attached garage. The chimney has 2 flues- one in basement and one for fireplace. When I measure the width of face of fireplace in den, it measures 66 inches. When I measure the rear of fireplace in garage, it is 60 inches. I would have figured the measurements would be the same. Is this common?

 

[bholler]

My masonry chimney is in my den and the rear of chimney is in my attached garage. The chimney has 2 flues- one in basement and one for fireplace. When I measure the width of face of fireplace in den, it measures 66 inches. When I measure the rear of fireplace in garage, it is 60 inches. I would have figured the measurements would be the same. Is this common?

Yes it is usually the case that the face is wider than the chimney structure