How to drill a 6" hole in the chimney

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rubantin

Member
Hearth Supporter
Jan 27, 2007
28
My wife wants a wood stove on the main floor instead of the basement. Problem is, there is no hole there. It is a clay lined cinderblock chimney. The local rentall place has a hammer drill with a 5" core dry bit that they say should work. I was reading somewhere that the clay lining requires a core drill.... Does it matter if I use a hammer drill with a core bit? I don't wat to have touble with the clay lining...
 
I have done this before. I would use a core drill. Many hammer drills have a drill only without hammer setting and in that case they can be used as a core drill. I used an SDS Max hammer drill with an option to turn off the hammer. I cored 14" without issue.

The real question is why a 5" hole? Most flue pipe are 6" and I wouldn't just dump the flue into the hole and out the chimney. I'd make a 6.25 or 6.5 hole and run your pipe through the hole and connect it to a chimney liner. There's fittings you can use to attach a thimble type connector to a liner in the chimney. I'd use an insulated liner to to get the best efficiency and chimney health.