Outside
dimensions Inside
Area of of standard diameter of
fireplace rectangular standard round
opening flue lining flue lining
--------- ----------- --------------
_Square
inches_ _Inches_ _Inches_
600 8½ by 8½ 10
800 8½ by 13 10
1,000 8½ by 18 12
1,200 8½ by 18 12
1,400 13 by 13 12
1,600 13 by 13 15
1,800 13 by 18 15
2,000 13 by 18 15
2,200 13 by 18 15
2,400 18 by 18 18
2,600 18 by 18 18
2,800 18 by 18 18
3,000 18 by 18 18
[D] Based on a flue area equal to one-twelfth the fireplace opening. Sec
table 2 for areas of flue lining.