Oil Furnace flue pipe clearances/pipe type in finished space

kylej Posted By kylej, Feb 25, 2013 at 11:22 AM

  1. kylej

    New Member 2.

    Sep 14, 2011
    Redding, CT
    View attachment 94974 I'm renovating my basement, and there is a short section of oil furnace flue (6") that comes through an interior stud wall into the finished space, and then elbows into the masonry wall to reach the bottom of the chimney. It's currently single wall 6" pipe. When we bought the house it came through a wall with wood paneling (using a thimble). We ripped that down, used fire batt and put up drywall. I realize these photos are still not up to code as the drywall is too close to the pipe, and that you are supposed to have 18" clearance to combustibles, but this condition is better than when we bought it. As I see it I have three options:

    - Replace the straight length of pipe with class A insulated pipe. I'd use an insulated thimble (do I need one on the interior partition and at the masonry partition as well?) Dura-vent and similar doesn't seem to sell 90 degree elbows.
    -insulate the existing pipe (can I do this and still be allowed 2" clearance to drywall?)
    -cut the drywall I put in already back 18", and use cement board instead. Keep single wall pipe and get a new thimble. This room will be a kids playroom so I'm inclined to do something to keep the pipe temp down to the touch just in case even though its out of reach.

    One other thing I should add is that I think the elbow needs to be removable so they can clean out the bottom of the chimney.

    You can see how close this is to the wall in the second photo (shot from below). The wall without the thimble in the pic is 1/2" drywall on furring strips attached directly to the foundation. Any advice would be appreciated!

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  2. begreen

    Mooderator 2.
    Staff Member

    Nov 18, 2005
    South Puget Sound, WA
    Yikes, saying this is better than before is not saying much. That's like saying you now have tires on the car and eventually will get around to adding brakes. 18" clearance is what's called for. Cement board would have been a better approach but there would still be studs behind the sheet. I'm not sure what all the options are here, but don't run the furnace as is.
  3. woodgeek

    Minister of Fire 2.

    Jan 27, 2008
    SE PA
    Can you bump out the wall in the corner so the pipe doesn't go through it?? I assume the area you are standing in the photo will be finished....seems you could bump out the corner, removing the sight of the pipe...and maybe put a short closet underneath for storage???
    343amc likes this.

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