Round Stainless Steel Insert Boot

A round stainless steel insert boot is designed to make the connection from an insert between a square or rectangle flue outlet and a round chimney liner.  Many old style fireplace inserts have a rectangle flue outlet.  This is because at one time they believed it to be OK just to set the stove inside the fireplace and call it good.  This is no longer the case.  Now we know of the dangers caused by this type of install.

What size Insert Boot do I need?

Every stove needs a proper size chimney liner for proper draft.  The square inches of the outlet on the stove needs to be as close as possible to the amount of square inches of the chimney liner.  First, you measure the length and the width of the flue outlet on the stove (as seen in pic).  Once you have your total square inches, you now know what size of insert boot you need.  insert boot

Insert Boot Measurements

A round chimney liner is designed to be mechanically mounted to the insert boot.  The insert boot will also need to be screwed to the top of the insert.  You need to install an insert boot that will accept a chimney liner that can handle the same amount of square inches as the outlet on the stove.  This means for example, if your measurements are 4″ x 9.5″, your total square inches are 38″.  Now it is as simple as finding a chimney liner that will handle 38″ square inches.


In conclusion, you will simply use the above chart to discover what size chimney liner you need and what size round insert boot you may need also.  One possibility that you may encounter is, on some stoves, the flue outlet is extra large.  The average insert boot may not cover the flue outlet.  Do not worry.  Give us a call and we can make one to any size you need.   If you are still confused or have other questions about purchasing and installing a chimney liner and an insert boot, please contact us 1-866-941-5112 or visit us on Facebook.

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