I just got an older wooden insert, Regency(R12).It is 6” from the collar on the stove,can I reduce to 5".Masonry fireplace side of the house,my flue pipe is 13-8"outside-inside 6-11" it is no room to put 6" flexible sts liner in there.I but 5" pipe and reducer from 6-5" weet inspector gonna accept that.I am in Canada Ont.
Thanks
Thanks