Addition Around Brick Chimney

Adenmoor

Hello all,
I've been working on an addition to my house.

We are keeping an existing fireplace with a brick chimney. I have already framed around the chimney but still need to have the existing chimney extened about 5 feet.

The chimney used to be outside the house but will now be enclosed. Is there anything special I need to do with the chimney itself?
I've heard that I need to demo down to about two feet of rebar before adding back upward. Is this true?
Is it possible to frame a new chimney made of wood built ontop of the existing chimney?

I live in Los Angeles County.
Thanks!

Adenmoor

I have found out that I have a clay flue.

Does any one know wher I can get a clay flue extension or adaptor so that I can extend using a galvanized flue?
I've called Home Depot, Ganahl Lumber, Lowes and All American; neither knows or has what I need.

Thanks!

two kids

Will you be burning wood in this fireplace....the only way you can build a wood chimney over a masonry one is if you are going to all gas logs.....but I would still check your local codes ...this is a fairly big deal since if you do it wrong it will heat up and burn down your house....Here in TN they will not even let us use block to fill the chimney solid anymore,,due to the chimney getting so hot it turns the block into dust....we have to use brick now.