Difference Between Liners – Rigid vs Flex

So you’ve been wondering – what kind of chimney liner do I need for my home? Well, there are a number of different factors that you will need to keep in mind that will help you on the way to making your decision. The chimney liner is usually the ultimate solution to many problems that plague a chimney. There are two different types of liners on the market – rigid and flex liners. While you will be able to find different sizing and types of these liners, these are the two main categories that they will fall into.

Let’s start off by discussing rigid chimney liners. You are able to use a rigid liner if you have a nice, straight chimney. These liners are thick, durable, and very easy to clean. Rigid liners come in separate sections that are usually round in shape. Generally made from stainless steel, rigid liners most commonly have a wall thickness of 24 or 22 gauges. The rigid liner pipes will come in separate sections that you join together using different crimps, pop rivets, and stainless steel screws to help secure the joints. Many times screws can work themselves loose, which is why pop rivets come highly recommended. These screws can become loose during the expansion and contraction of the liner due to heat.

Flexible chimney liners work in the same way that rigid chimney liners do, however, they work best if your chimney is not perfectly straight or has any jogs or offsets. This type of liner is the most cost effective for relining your chimney. Flexible liner comes in different thicknesses – some are lighter and heavier than others. All flex liners have some sort of ribbing, and are available in a number of different lengths. The great thing about flexible liners is that they allow for both top and bottom support because any expansion is absorbed by the liners flexible ribbing. Some flex liners can easily be bent by hand, while more heavy duty liners will require tools.

Overall, it all really boils down to the functionality and cosmetics of your chimney. Is it straight? Does it have any offsets? These are the big questions that will help you on your way to discovering the right chimney liner for you. Good luck!