Results 1 to 5 of 5
  1. #1
    Join Date
    Jun 2008
    Location
    Corpus Christi, TX
    Posts
    10

    Default Direct vent chimney shroud

    Saw this today. Direct vent fireplace chimney terminates in a shroud constructed of hard coat stucco, open at all four sides with about 9 to 12" clearance. The top of the shroud is fiber cement soffit material. Manufacturer's installation and clearance requirements are not on site. See any problems here besides a shroud that is not listed for this appliance?

    Similar Threads:
    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    Member Benefits1

  2. #2
    Join Date
    Mar 2007
    Location
    Near Philly, Pa.
    Posts
    1,682

    Cool Re: Direct vent chimney shroud

    When you refer to problems with the shroud other than the question of a listing, I hope you are referring to the probability of combustible construction.

    As for the vent termination, I highly doubt it extends far enough up through the chase top. That storm collar appears to be blocking the combustion air intake. Also, how is this pipe penetrating the chase top? Is there a 2" raised collar? What is this chase top constructed of?Does the mfr. require a min. size hole to ventilate the chase?

    Also note that tall direct vents usually require a special baffle installed inside the fireplace. While this is beyond the scope of a home inspection, it is a very real consideration, which is all the more reason to recommend a qualified technician inspect and test this appliance with the listed instructions made available on site. He could also verify this vent pipe is listed for use with this fireplace and how.

    Keep the fire in the fireplace.

  3. #3
    Join Date
    Jun 2008
    Location
    Corpus Christi, TX
    Posts
    10

    Default Re: Direct vent chimney shroud

    Thanks Bob. All good questions. Since the construction around the vent termination is all non-combustible stucco and fiber cement, the only combustible issues I would be concerned with are the framing members behind the non-combustibles. There is no metal chase pan here; the vent penetrates through stucco and I'm not sure if there is adequate clearance from any wood sheathing supporting the stucco. Good point about the storm collar clearance. I will recommend evaluation with mfr's instructions on site.
    Thanks again.


  4. #4
    Join Date
    Jun 2010
    Location
    San Luis Obispo
    Posts
    26

    Default Re: Direct vent chimney shroud

    The cap looks too short, can't see the air intakes. Yes unlisted shroud.

    [quote=Marc Robin;166104] Since the construction around the vent termination is all non-combustible stucco and fiber cement, the only combustible issues I would be concerned with are the framing members behind the non-combustibles. quote]

    In my world of fireplaces a non-combustible stucco and fiber cement wraped and covered 2x4 is still combustable construction. Thing is cement, steel etc are not insulators they conduct heat. I would only reduce the clearance by the thickness of the non-combustible. Any shroud that has any combustable materal at all fails the requirements.

    Chimney shroud's must be 100% non-combustable. This shroud has many issues and needs to be removed and a proper one installed if allowed by the pipe mfg.


  5. #5
    Join Date
    Mar 2007
    Location
    Near Philly, Pa.
    Posts
    1,682

    Cool Re: Direct vent chimney shroud

    When you assume the hard coat stucco is non-combustible, I would advise a closer look. Not all fiber cement boards have passed ASTM E-136 so they cannot be ASSumed to meet the std. as to what is non-comb. We don't know if the framing is wood or metal or a combination. Keep in mind metal studs can conduct a lot of heat. Now, is there grade D paper behind that stucco? Lot's of questions remain.

    If they penetrated a sheet of non-comb board as the chase top, it still needs a 2" raised collar to keep out wind driven rain and hopefully is pitched for drainage.

    Keep the fire in the fireplace.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •