Rectangle Chimney Liner Conversion Chart - Chimney Liner Size Chart

This chart is designed to assist you in selecting a rectangle shaped chimney liner. The key when calculating the measurement of a shaped liner is to match as closely as possible the area in square inches of a recommended round liner. Complete instructions are included below the chart. You can also try our Liner Shape Calculator.

Please give us a call at 1-866-708-2446 to confirm your dimensions before placing your order.

Rectangle Chimney Liner Conversion Chart

Original (Round) Liner Dimensions
Diameter 5" 5.5" 6" 6.5" 7" 7.5" 8" 9" 10" 11" 12" 14" 16"
IN² 20 23.75 28 33.2 38 44.2 50 64 79 95 113 153.9 201
Converted (Rectangle) Liner Dimensions
Minor
Outside
Dimension

Major Outside Dimension
4" 6.25" 6.87" 7.25" 8.06" 8.93" 10.06" 10.93" 12.56"          
IN² 21.29 23.54 24.92 27.85 31.01 35.1 38.26 44.17          
4.5" 5.62" 6.25" 6.62" 7.56" 8.43" 9.56" 10.43" 12.06" 13.62"        
IN² 21.63 24.23 25.76 29.63 33.22 37.88 41.47 48.2 54.63        
5"   5.62" 6" 7.06" 7.93" 9.06" 9.93" 11.56" 13.12" 14.62" 16.25"    
IN²   24.25 26.01 30.91 34.94 40.16 44.19 51.73 58.94 65.88 73.42    
5.5"       6.56" 7.43" 8.56" 9.43" 11.06" 12.62" 14.12" 15.75"    
IN²       31.69 36.15 41.94 46.4 54.76 62.75 70.44 78.79    
6"       6.56" 6.93" 8.06" 8.93" 10.56" 12.12" 13.62" 15.25"    
IN²       34.79 36.87 42.22 48.12 57.29 66.06 74.5 83.67    
6.5"           7.56" 8.43" 10.06" 11.62" 13.12" 14.75"    
IN²           44 49.33 59.32 68.87 78.06 88.04    
7"           7.56" 7.93" 9.56" 11.12" 12.62" 14.25"    
IN²           47.6 50.05 60.85 71.18 81.12 91.92    
7.5"             7.43" 9.06" 10.62" 12.12" 13.75" 17.25"  
IN²             50.26 61.88 72.99 83.68 95.29 120.05  
8"               8.56" 10.12" 11.62" 13.25" 16.5"  
IN²               62.41 74.3 85.74 98.17 124.65  
8.5"               8.06" 9.62" 11.12" 12.75" 16.12  
IN²               62.44 75.11 87.3 100.54 128.97  
9"                 9.12" 10.62" 12.25" 15.75"  
IN²                 75.42 88.36 102.42 132.85  
9.5"                 8.62" 10.12" 11.75" 15.37"  
IN²                 75.23 88.92 103.79 136.37  
10"                   9.62" 11.25" 15"  
IN²                   88.98 104.67 139.45  
10.5"     Rectangle Liner Size Chart - Call (866)-708-2446 With Any Questions     9.12" 10.75" 14.50" 18.00"
IN²         98.54 105.04 141.67 175.78
11"                     10.25" 14" 17.50"
IN²                     104.92 143.42 179.28
11.5"                     9.75" 13.50" 17.00"
IN²                     105.46 144.74 182.28
12"                       13" 16.50"
IN²                       145.48 184.78
12.5"                         16.00"
IN²                         186.78
13"                         15.50"
IN²                         188.31
13.5"                         15.00"
IN²                         189.31
14"                         14.50"
IN²                         189.81
14.5"                          
IN²                          
15"                          
IN²                          

 

How to use the Shaped Liner Conversion Chart

 

Step 1: Determine what diameter of round liner is recommended for your stove, fireplace, or other appliance. You should also know the inside dimensions of your flue.

Step 2: In the top (red) section of the chart, locate the number that represents the round liner diameter you need. Then look below it for the red number that indicates the area in square inches. Example: An 8" round liner has 50 square inches of area.

Step 3: Look at the rectangle (blue) section of the chart. The numbers of the left side of the chart indicate possible Minor Outside Dimensions; the numbers on the right are possible Major Outside Dimensions. The red numbers indicate the area in square inches for each Major OD x Minor OD combination.

Start by eliminating all the black numbers in the left column (Minor ODs) that are equal to or greater than the Minor Inside Dimension of your flue. Look for the red number (square inches) that is closest to the area of the round liner you found in Step 1. Make sure the number you select is within 2 square inches of the round liner area. Eliminate all the Major ODs that are equal to or greater than the Major Inside Dimension of your flue.

Step 4: Once you have found your match in square inches, the black number above it with be the Major OD of your rectangular liner. Follow that row horizontally to locate the Minor OD on the left side of the chart.

You have now found the two numbers that will be used for the dimensions of your shaped liner! Please give us a call at 1-866-708-2446 to confirm your dimensions before placing your order.

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Our 316Ti flexible chimney liner and chimney liner components have passed the rigorous testing at the Underwriters Laboratories with best in class status and are UL Listed. So if you are looking for UL listed chimney liner sold directly to homeowners, then look no further than Rockford Chimney

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