Class A transition to single wall

[cmcramer]

My Class A chimney (20 year old Selkirk "Metalbestos" ) travels straight down to my walk-in basement, ends between floor joists, flush with the bottom of the joists. The carpentry crew that built my house and installed the Class A, fabricated their own suport system between the joists: it's not the Class A fitting I see in the online manual or at a dealer's shop.

How can I determine if it "meets code"? Can any customized, fabricated support system meet code?

I guess I am asking, just what does the "code" state?

And are the manufacturers the keepers of the code, with no one else able to produce a support system that meets safety codes?

Thanks!

 

[porkie]

All class A chimney systems are UL or CSA tested and only parts for each brand must be used as there are tested as a system
and only those pcs can be used you can't change parts from one brand to others

 

[jtp10181]

what porkie said,

also I can add if it ends flush with the joists, its too short you would need to extend it down a bit further according to what the pipe mfg specs, prob 3-6 inches if you plan to connect double wall black pipe, not sure about single wall, might need 18" down.

Also the matter of the code is that most codes regarding prefab systems simply say "must be installed per manufactures instructions" and most of the mfg's instructions state you can only use their components, and anything else voids the listing and warranty.