Raising a cast iron flange?

[ario]

Hello,

I have cast iron flange and waste pipe on my first floor toilet. We are going to remove this toilet and everything else and put down cement board and then tile. Currently it's vinyl over hardwood. Is it possible to raise the flange with some kind of adaptor about 1"? Or do I have to break apart this thing? If so, how does that work? I have plenty of experience on the supply side of plumbing, but have done little on the waste side. Thanks very much in advance.

[e-plumber]

http://img.photobucket.com/albums/v196/e-plumber/closetflangeextender.jpg

If the flange is in good condition, an extention kit could be used but the flange will not sit on top of the finished floor anymore. Make sure that the existing flange is very secure before installing the kit.
The ones with rubber gaskets in between the layers are the better type.