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Community and Q&A

Fireplaces in Tight Houses

Chris Baddorf | Posted in Green Products and Materials on

We are building a custom house with SIP walls and SPF roof. Manual ventilation will be installed. Plans were originally for a 2×6 enclosure and an unvented fireplace. The research I’ve done says unvented fireplaces in a tight enclosure are a bad idea but the client (my wife) doesn’t like the look of an exterior chimney.
Is there a way to vent a fireplace unobtrusively? Or, can I get a way with unvented gas logs if I supply make up air?

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  1. David Meiland | | #1

    Unvented, as in combustion byproducts vented into the living space? In a tight house??

  2. Gordon Taylor | | #2

    "In a tight house?" Hell, in any house. What's wrong with a normal sealed-combustion fireplace? The exterior exhausts on those are extremely unobtrusive, I think. (I'm hoping I can talk my wife into one of those.)

  3. Michael Chandler | | #3

    Try the regency HZ42 "contemporary" sealed combustion natural gas or LP fireplace with wall mounted ignition switch, outside combustion air, horizontal "astro-cap" venting, and 26,000 BTUh heat output. I think it will make the client happy and keep the air safe in your home at a reasonable price. The P33 is a nice one if you want to go smaller @17,000 BTUh

  4. Gordon Taylor | | #4

    To Michael Chandler:
    Do you know of a sealed combustion natural gas fireplace that has a really LOW heat output? I assume the units you've talked about can be turned down, but what if you really don't want a lot of heat to begin with? Like Mr Baddorf, I'm trying to satisfy a very particular client, my wife.

  5. GBA Editor
    Martin Holladay | | #5

    If you are building a tight house, you need a mechanical ventilation system. I don't know what you mean by "manual ventilation," but you probably mean something like "we'll open the window if the air seems stuffy." That's not an adequate approach for a tight house.

    I agree with the other respondents about the importance of avoiding a "vent-free" fireplace. Either you choose a fireplace with a vent, or you don't install a fireplace. You don't want to be breathing gas combustion byproducts inside your home.

  6. Chris Baddorf | | #6

    The direct vent is what I'm looking for, thanks. I looked at the regency site and I think they have a style we can work with.

  7. Chris Baddorf | | #7

    The smallest BTU output of the regency fireplaces is 10,500. I don't know if that is small enough for you.

  8. Chris Baddorf | | #8

    I meant to say mechanical ventilation, but it was way past midnight and manual was the best I could come up with. I knew vent-free wasn't going to work but my wife was seriously talking about scrapping the entire house plan if we couldn't install a fireplace. Thanks for the help.

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