Old Fireplace Blues

Hi. We purchased a beautiful home that was built in 1888. The home is all brick including internal walls. We wanted to put a wood burning fireplace insert into the existing fireplace, but when the installer came out to install it, he told us that the chimney opening was too small for the chimney liner needed for an insert. Also, there are a couple of bricks missing, and mortar missing or fragile, and the firebox itself is an odd shape at the rear. We are prepared to either hire a mason, or attempt to repair the brick and mortar issues ourselves, but is there anything we can do to enlarge the chimney opening? Is there any such thing as a large dremmel tool to simply make the opening larger? Can you offer any guess as to what it would cost to build a new chimney? We don't want to tear the fireplace down because it's beautiful and looking deeper into the entire scheme of things, we believe it's a part of the homes structure. Stumped!
Thanks for any insight you can offer.
Sylvie

 

You can't "ream out" the existing flue. It's a special clay liner designed to contain hot exhaust gas. Normal brick, concrete or concrete block is not capable of providing this function.

If the fireplace currently works and there are no problems then you might be able to install a direct vent gas insert [ normally this requires (2) 3" diameter flexible ducts - 1 for supply air and 1 for exhaust.] ]

I would doubt that the existing flue is too small to snake these down thru the existing chimney. 5" x 9" would be tight but possible depending on the height.

Otherwise, rebuilding would be the best bet. I would be surprised if the fireplace is part of the building structure. This is very rare. Usually a fireplace and chimney are built as a separate independent structure from the home. In fact, by todays' building codes this is imperative.

Get a mason (or preferably 3) to look at it and give you bids. Rebuilding won't be cheap in any case.