Hi folks, great forum you have here. I've been lurking around doing as much reading as I can... very useful! We are planning to put a Regency i1200 insert in our old open fireplace. Our house is a 1924 arts + crafts 2 storey house in Nova Scotia, with an exterior chimney (see photo). The chimney is in bad shape, so is getting repaired/repointed and lined before we install the insert. The WETT-certified mason/sweep said we could use a 5" liner, because our chimney is high enough to compensate for the smaller diameter flue. This would also save us the cost of breaking out the existing clay liner (~$450). The Regency documentation says 6" is the min. Does that raise any alarm bells with you folks? Has anyone else got a similar setup (undersized flue, small insert, tall chimney)?