Stainless Steel Chimney Liner Kits -- 316Ti, Made in USA

The diameter is measured on the inside of the (inner) pipe. Common sizes are 4", 6", and 8", depending on your appliance. A 4" liner is typically used for gas appliances and some pellet stoves. Most wood stoves use a 6" internal outlet, while larger stoves or open fireplaces may need 8". Check your appliance manual or look at the round collar where the flue connects.

Our flexible liner grade 316Ti is suitable for relining masonry flues and for use with wood stoves, multi-fuel stoves and open fires.

We recommend taking some extra length. If your liner is not long enough for your installation there will undoubtedly be delays and disappointment, plus the extra cost of a correctly sized liner. Adding an extra foot or two helps ensure your installation goes ahead without delay.

There are two ways to connect the liner to your appliance. Choose the one that matches your setup:

Top connection (adapter in the top of the stove): the liner runs straight down the chimney and connects to an appliance connector on top of the stove, in a straight vertical line with no bend. Choose this if your stove sits directly under the chimney and vents straight up. This kit includes the appliance connector, the no-sag top plate and the rain cap.

Tee connection (tee in the back exit of the stove): the liner connects to a tee at the base of the chimney, and a short horizontal snout passes through the chimney wall to your appliance. Choose this if:

• your stove stands in front of the chimney and the stove pipe runs back into the chimney wall, or
• you are relining a fireplace or a chimney with a thimble (a round hole in the wall where the pipe enters).

This kit includes the tee and snout for that side entry.

When do you need an insulated liner?

It depends mostly on your fuel.

Wood or coal: insulation is normally required. A 1/2 inch insulation layer between the liner and the masonry gives the liner its zero-clearance listing, which means the chimney is safe even when wooden framing sits close to it. It also keeps the flue gases hotter, giving a stronger draft and less creosote build-up. For wood especially, this is the safe and code-compliant choice.

Gas or oil: insulation is usually not needed. Forever Flex is listed to be installed without insulation for gas and oil in a brick or clay-tile chimney that is in reasonable condition.

Approved chimney: even for wood or coal, you can sometimes skip insulation if your masonry chimney is sound and already provides the required clearance to combustibles, and your installer or local code confirms it. That is what the "approved chimney" choice means.

There are also reasons to insulate regardless of fuel. For safety: insulate when the existing flue is cracked, or when there is not enough air gap between the masonry and nearby woodwork. For draft: insulation helps most on a cold exterior chimney, an oversized flue, or where the draft was already weak. If your chimney drew well before the reline, you do not need to insulate just to improve the draft.

Why the woodwork matters: a masonry chimney is rarely free-standing. Floor joists, rafters and roof boards usually sit against or very close to it, and older homes often have this framing tight against the brick with no air gap. Insulating the liner keeps the heat inside, so the outside of the masonry stays cool enough even when wood is close by.

No room for the blanket? The blanket adds about 1 inch to the liner diameter, so a 6 inch liner needs roughly 7 inch of clear space. Never use a liner smaller than your appliance's flue outlet, so going down a size is only an option if a smaller liner still matches your stove. If you cannot go smaller, then for gas or oil you can install the liner without insulation. For wood or coal, installing uninsulated is only safe when there is already enough air gap between the masonry and the wooden framing around it, which you often cannot see from inside the room, so check with a professional if you are unsure.

Not sure what your setup needs? Contact us for a free design check.

What does a pulling cone do?

A pulling nose cone fits over the end of the liner and gives it a smooth, tapered tip. That lets the liner, and its insulation, slide down through the masonry chimney without catching on ledges, offsets or rough brickwork, and it stops the insulation from bunching up or tearing during the pull. The result is a faster, easier installation with much less risk of a stuck or damaged liner.

Can you do it without a cone? Yes. A common method is to push a piece of stiff iron wire through the end of the liner, twist it to hold, and tie a rope to it, then pull the liner down from above or below. It works, but without the smooth nose of the cone the open end of the liner catches more easily on the way down, so it is more likely to snag or get stuck, especially in an older or uneven flue, or when the liner is insulated.

Our advice: use a cone for an insulated liner; for a bare liner in a clear, straight flue the wire-and-rope method is usually fine. The cone is reusable, so many installers already have one. We supply the cone in the matching diameter for your liner.