The time is near i can smell the wood burning but still need just a little more help to insulate or

I can't tell you what size hole, but if your putting a liner through a chimney that has no liner, you need to insulate the liner.

Is the class A servicing another woodstove? If you want to be safe and code compliant, insulate the liner. Most stove shops will say you don't need to, not sure why, easier for them I guess.

My fireplace is in the center of a single story ranch style home. The chimney isn't lined and the inside is made with brick and mortar...

The length of the 6" uninsulated liner is 13' from insert connection to 4" above the dome of the chimney. The chimney has a 1/4" thick plate to completely seal it, except for the 6" hole for the liner. The stove shop boys said that here in North Central Texas, the liner heats the sealed chimney's dead air space so the liner stays hot and won't build up. Our low temps can rarely reach the single digits for more than one or two days in a row.

The main issue they had installing it was getting the 6" liner through the old damper "slot", and had to impact hammer out some brick for clearance.

Does your liner run the full length of the chimney and is sealed with a metal plate?

Bill

It's not a matter of heat for draft, it's a matter of you and your family's safety. If you install the liner in an existing chimney that does not already have a clay flue, you need to insulate it to meet code. Heck, I have an interior chimney with a clay liner and I'm still going to dump some perlite down that sucker to insulate it.
Spend the extra money and do the installation the right way.

Could you show me where and what code you are referring to?

Thanks,
Bill

I believe it is UL 1777 for the liner and NFPA 211 for the chimney. Do a search on here for liner insulation. I don't think you will find many people recommending an uninsulated liner in a chimney that does not have a clay flue. Even with the clay flue in my chimney, the liner transfers a lot of heat into the masonry and will heat up the sheetrock chase that the chimney is enclosed by.

Cowboy, I wish the site I was going to link you to was still up, but the site has changed domain names, and the article is no longer there. It was an article on NFPA 211 and UL 1777. The thing about insulation is everyone assumes it is for the purpose of getting a better draft. Though it can assist draft by keeping the flue gases warmer, the REAL purpose of that insulation is to protect the masonry structure in the event of a chimney fire in the liner. Most masonry chimneys were not built to code - some estimates go as high as 90% being wrong. They require 2" clearance from the outside block and 1" clearance from the liner material to the block on an interior chimney (if I recall correctly). For an exterior chimney, the block is required to be 1" from combustibles and, again, the liner inside the block must have a 1" air space between it and the block. Apparently few chimneys followed this convention. The liner insulation is there to bring the chimney up to code by making sure the heat from the liner is not transfered to the masonry material in the event of a chimney fire.

That was the gist of the article. Someone certified/more educated please correct my post if it contains misleading insights, but that is what I took from that article when it was up.