Double Wall Chrome Mirror Finish Chimney Flue

[brthomas]

I have a question regarding finishing around a double wall chrome mirror finish chimney flue. First off I am a finish carpenter and do not really do much drywall finishing except as when needed such as this instance.

Should there be insulation in the rafter bay that the flue is in? I was going to head off the bays and remove the insulation that is in direct contact with the flue itself. Then proceed to the next question.

Finishing, can I finish tight around the flue or should there be an expansion joint? I feel there should be, but with a double walled flue I am not 100% certain.

Lastly, I would have looked this up and spent time on finding an answer on here but, it has been a long 14 hour day and frankly looking is the last thing I would like to be doing right now. Especially with invoices to type still.

Thank you very much for your time and input.

[tjbnwi]

If you know the brand, that would help answer your questions. The install specs will list the clearances. The manufacture may have a ceiling thimble to cover any gap, much like a pipe escutcheon.

Heartman may be by with all your answers off the top of his head.

Tom

[brthomas]

I regretfully do no have any info on this flue. I was just asked to do a ten sheet job and fix a few small things in the home prior to finishing. The house was someone else's project that was purchased by the now new HO and I was called in as stated in the above to hang and finish and trim out the room.

I will look again today and see if I see any branding and report my findings.

Thanks Tom for your help, it is most appreciated.

[tjbnwi]

The flue pipe may be fireplace manufacture specify. So they may need to know the brand to get the proper fireplace.

Tom

[charles]

I'm thinking the type of insulation could be relevant. Cellulose and foam, no contact. But fiberglass possibly and mineral wool probably.

You'll need to use a high-temp caulk at the thimble or whatever joint you decide.

[brthomas]

I looked intensively at all of the piping today and couldn't fine a single thing that refers to a branding, parts number, or anything to base my research off of. It's just all mirrored finish double walled insulated pipe.

The fireplace itself is an old wood burner that has been connected to all new flue pipe and adjoining pipe compenents and finlly exiting into and impressive chimney set up. It looks really impressive to me as it isn't "the norm".

I called a local company that specializes in this kind of work and was referred to Copperfield Chimney Company out of the Midwest. So I will be calling them tomorrow during break to look into my options.

The head of their technical service department recommended giving the pipe a 6-8" air space around it in the rafter bays so that the pipe has no combustible products like insulation or anything of the like and to make sure it is all protected from the pipe. Any form of insulation he stated could in fact super heat the area and add to the likelihood of combustion. In addition he had recommended that the ceiling surface have a 1'-3" gap between the pipe and the ceiling surface (IE: Drywall and or T&G boards).

I will let you know my findings again with Copperfield Co. to keep you informed on this thread.

As of today though the ceiling was just changed to T&G Pine instead of drywall as originally planned. This makes me happy (by trade of course as my reasoning). So if need be Moderator you are welcome to remove this topic and replace in finish carpentry forum as needed.

Thank you all for your comments, and again I will let you know how the finished product works out.