do i have to insulate my liner

[iceman]

I am getting Mflex liner kit anyone heard of it?
stove shop says i don't need insulation because
1) my chimney is interior
2) the chimney has never been used ... inspector said its in brand new condition (chimney insp)\
do i need to insulate

also i have a custom cap and stoveshop says since i am going to install blockoff plate at the bottom i don't need the collar plate at the top he says the liner is hard and will fine sticking out of my flue an inch or so but i don't need to spen the extra fifty to by the plate
is this true or is some one beating me in the head
By the way, he is charging me sep for pieces for 25' liner and connector to the stove ists 337 after discount
your thoughts please

 

[Turner-n-Burner]

-Price sounds pretty good.
-You Need the collar plate and a rain cap. they should come together. Otherwise your liner is free to sag or sway in the wind. Doesn't seem like a good idea to go without unless your existing cap can support the flex liner.

- I wouldn't worry about insulation. I have an exterior chimney and a 6" un-insulated flex chimney liner. It drafts great! I would have insulated if it would have fit. (actually bought and returned it). But now that I know how well the chimney drafts, I don't mind the money I saved!

-Dan

 

[Todd]

If the chimney has clay tiles you don't need insulation wrap. Get the collar and cap, water will get in without and cause damage.

 

[iceman]

i have a custom cap already .... i have a total of 6 flues all under 1 gigantic cap that is why hey says to just let it be i thought i would at least need the collar plate but he says the liner is so stiff if i bring it out an inch i will be fine its running a total of 15 to 17'

 

[BrotherBart]

i have a custom cap already .... i have a total of 6 flues all under 1 gigantic cap that is why hey says to just let it be i thought i would at least need the collar plate but he says the liner is so stiff if i bring it out an inch i will be fine its running a total of 15 to 17'

He is full of it. The top of that liner needs some kind of support. If for nothing else the fact that it is going to compress a little back down into the flue when you run a stiff cleaning brush down it. At the very least it needs a support collar of some sort on top of the flue tile holding it up. No flex liner goes into a chimney arrow straight. Think snake here. When you pull or push the brush down it compresses it more into the flue.

And blowing rain is going to go right through the screen in that mega cap of yours and down the chimney around that liner. And that beautiful heat that should be trapped in the flue tiles giving you wonderful draft is going to be flying out the top heating the neighborhood while your draft is crap.

If nothing else mortar the top of the liner in with refractory cement. Twenty bucks a bucket at HD.