Question on insulating a flu liner in a zero clearance fireplace

[jlightning]

I have been to a couple of stores shopping for a new insert for my zero clearance fireplace and have almost everything figured out for installation except for insulating the flu liner. One of the stores says its the law and they have to do it and another store didn't even mention it in the flu installation. Should I have the insulation put in or don't I need it? What is the benefit of having it?

 

[shawneyboy]

If it is the "law" or not, that I can not answer.

As to the benefits....

An insulated liner helps keep the flue hot. Keeping the flue hot means you can establish a better draft and the moisture that is created when burning and any flamable gasses can not, or are less likely to, condense in the flue, this means less creosote is created.

Shawn

 

[double-d]

jlightning
As shawneyboy mentioned insulation is always good. It is usually recommended that you insulate when installing your chimney liner, with either a blanket wrap kit or a pour down insulation mixture . Insulating will increase the efficiency and minimized creosote buildup. A properly insulated chimney will provide warmer flue temperatures. This ability to maintain warm flue temperatures will also have a positive effect on draft. The warmer the chimney, the warmer the gas; the warmer the air (gas), the faster it rises, thus creating a much improved draft and maximizing the efficiency of the insert.
Make sure the insert is approved for your zero clearance fireplace. You didn't mention if this was a brick and mortar chimney or prefab chimney, they take different liners.