Found this forum, looks perfect, lots of info... I've done lots of research but still a lot of questions. ... hope I can benefit from your experience... I want to install a Hampton insert in my solid masonry fireplace. Facts: -2 story central plan house built in late 20s, solid brick, external chimney about 30', living room fireplace about 450 sqft., not open concept but generally open first floor -existing 16" hearth over std cement pad built on basement joists, etc. -spoke with various vendors (WETT certified in Canada), contractors, masons, an architect, insurance agent, and the local building dept. -looked at many inserts. The contenders were Kennebec, Clydesdale, and Hampton. Settled on Hampton. - Have obtained and reviewed relevant sections of NFPA 211 (not applicable here), CSA B365, and Ontario Building Code -looked at various fireplace finishes. - Bldg dept say I need a permit. After sending me through 3 people, finally got someone who knows a bit but did not know what an EPA fireplace was and said we don't get too many of these permit requests (in a major Cdn city). Frankly this baffles me. All others (except the architect) said forget the permit. Proposed WETT installer also recommends I don't get permit based on his experiences. I believe in getting a permit but it appears to be a real challenge on all fronts. - The Hampton meets all combustible clearances but the only problem is that the firebox depth is too short by 1.5". Questions: 1) Facing / Surround: If the fireplace front is built out to meet the required depth, will this work from a form and function perspective? I am told that durock sheeting overlain on the existing tile face and then 1.25" granite slab face (my choice but $$$) will be OK. Granite vendor says there can be no gap behind it to prevent cracking. Should Micor or alternate be placed behind the durock? 2) Hearth: Will have to extend to about 25" from existing face to meet the 18" local requirement and accomodate distance from Hampton firebox door. If Micor is placed (glued) first, then durock (tapcon screw) sheet, then a granite slab (all over a 3/4" oak tg floor on std sub floor) will this work structurally to prevent granite slab cracking if kneeling on it? This is a 9" extension from the existing hearth. Note Micor will surpass the R=0.6 specified by Hampton. Thanks for your assistance.