Flex Liner Sizing Charts

How do I know what size chimney liner I need?

Please be sure to call us for help with sizing a chimney liner - 1-866-941-5112

Choosing a Length

The best way to size your chimney liner is by dropping a tape measure from the top of the chimney crown and measure the distance from that point to the thimble or opening where your appliance or stove will connect to the chimney. It’s always a good idea to add an extra foot or two just in case.

Choosing a Chimney Liner Diameter

A general rule of thumb is to see what size outlet is on your stove or appliance. In most cases, fireplace inserts require 6 inch diameter chimney liner. Wood stoves generally require between 6-8 in diameter chimney liners.

In any situation you should first consult the manufacturers instructions of your appliance before installing a liner.

Please call us before purchasing a Chimney Liner

Because chimney liners are extremely important to install correctly to keep you and your family safe, we always want you to contact us and confirm that the liner you are about to purchase is the proper size.

If you are planning on installing a liner for a gas or oil burning appliance, we need to know the total input BTU’s of all the appliances that will vent into the chimney liner.

If it is a wood burning appliance, we need to know the size of the flue outlet on the stove.

If it is an open fireplace, we need to know the height and width of the fireplace opening.

Please be sure to call us for help with sizing a chimney liner – 1-866-941-5112

liner charts



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