Replies

1. 
   DanH | Nov 15, 2012 07:45pm | #1

   All I know is that about 20 years ago, in order to make the inspectors happy in a H4H home I was working in, I had to figure out how to line the inside of the chase with drywall.

2. 
   florida | Nov 15, 2012 09:47pm | #2

   Build it just like any other wall.  You might have to line the bottom 4 feet with cement board but I've never had to.

3. 
   IdahoDon | Nov 15, 2012 10:39pm | #3

   The fireplace will have clearance requirements that have to be followed - often it's simply an inch from any combustible materials if it's the double wall type that is bringing in combustion air as well as exhausting out the center of the pipe.  The chase can be built like a wall, but to keep it insulated it's much better if you line the chase with something.

   When I built a chase I make it out of 2x6 to allow a decent amount of insulation and line it with osb.  Fiberglass is a poor insulation in cold climates in the best of circumstances and if you essentially vent half the insulation to the inside of the chase it's really crappy.

   Pay close attention to flashing and weather proofing since chases are probably the most common place to find leaks and poor craftsmanship.

4. 
   lynchfh | Nov 16, 2012 12:12pm | #4

   Thanks, guys.  I hadn't thought about lining the inside with sheetrock, that'd add stiffnes and shear also.

5. 
   DoRight | Nov 16, 2012 02:28pm | #5

   outside fireplace? Insulation?

   You might want to clarify your porject.  Is this an outside fireplace?  People here are talking about insulation which I don't beleive is necessary for an outside chimney.  Some might like insulation in either case to keep teh flue warm, bt if it is an outside fireplace I would guess the flue is pretty short and cooling would not be a problem.

1. 
   IdahoDon | Nov 16, 2012 11:21pm | #6

   lol - you're right - this is outside!  I don't think I'd insulate anything either :)