Insulated liner question

[mfglickman]

Our FV is connected to a brick chimney that runs up the outside wall of our house. It has a SS liner, installed last year, capped at the top. There is a block off plate of sorts (sweep cut a hole in the damper to run the liner). We stuffed some Roxul up there cause well, just because we had some left over.

So my question - should we actually add insulation to the liner? If so, at this point, how? The sweep says it's unnecessary, as is the Roxul, because the top is sealed, but I have a feeling it could be better.

We have decent draft, the only time we got smoke in the house was when DH tried to burn some mail instead of shredding it this summer....

 

[webby3650]

If the liner isn't insulated you might be better off without a blockoff plate. If it's blocked at the top and blocked at the bottom, the liner is hot and cold, hot and cold and so on. Insulation is so easy to install and not very expensive, I can't understand why so many installers balk at the idea. The only way to do it now is to remove the liner, wrap it and re-install. Insulation wouldn't help it draw in the summer though, but thats a whole different topic.