Fireplace delete in coastal California
I need GBA community’s help with a poor man’s not too deep energy retrofit on a 1962 ranch with the following attributes:
Single story, 8 foot ceilings, 2×4 walls, brick fireplace with no external wall bricks exposed. The firebox (wood burning with gas assist) is unsafe do to mortar issues and I have no desire to have a fireplace or insert. The above roof-line Chimney is in great shape and the mortar cap was redone in 2021. I hope to avoid the additional expense of complete removal although I am re-roofing this year. The previous owner had painted the chimney to protect the mortar and it seems to have worked well despite the fact that painting can cause moisture to be trapped and damage the bricks do to freezing in some climates. I’m in Zone 3 (C). I seek to eliminate drafts and thermal mass problems associated with this type of site built fireplace.
Because I’m also doing Popcorn ceiling removal the demo contractor offered to remove the (ugly/dated) facade while under containment for asbestos removal.
I hope to get your input on the following plan:
How to construct new wall and insulation to cover the remaining thermal mass of the firebox and chimney. I also plan to air seal the chase if the chimney stays. I would also like to seal the Chimney at the top as I expect no warm/moisture laden air to go up the chimney if it is walled off from the living space.
One additional piece of information is that a bedroom closet is located behind the back wall of the firebox if that matters.
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Replies
I think I paid around $300-$500 to have a chimney removed below the roofline by the roofer as part of a re-roof. That included patching the sheathing. I would do that and get the whole thing inside the building envelope for starters. That basically solves your sealing problem.
From there, I would look at removing the whole thing. It will free up a lot of space inside the house. Get a dumpster, and a bucket. Take it apart brick by brick, put the bricks in a bucket and carry them out to the dumpster.
Yes, I'm considering those options too. I'll have to get the timing right so I still have access to cavity that houses the fireplace for debris removal. The living room is pretty large so the extra space is secondary to thermal improvements. I'm thinking the roofers would be dropping lots of debris with no way to retrieve them unless I leave the wall open in the living room. To complicate matters, California had six atmospheric rivers come through in January so the roofers are telling clients they have 2 years of work scheduled.
If you are re roofing, boy this sure is the time to remove the chimney
Yeah, one story house it's really not a big job.
One concern about the removal is were talking Santa Barbara County Ca were prices vary greatly from other parts of the country. Good rule of thumb: just add a zero to prices experienced elsewhere.
The weight of the bricks alone, to dispose at a land fill, would likely far exceed the $300 to $500 DC_Contrarian paid. Post-Covid era especially. Not saying it won't be removed but in air-sealing, one has to chose their battles.
BTW Blower Door test results: the guy said his software won't even generate a report when the air loss exceeds 11 ACH. He was stunned to find out that there was so much leakage that he even got out some cardboard and carpet protection plastic and tried to block off the fire place and HVAC closet to no avail.
In any case, would anyone like to suggest how to detail the rebuilt wall as to vapor barrier? I'm willing to lose rather than gain interior space to achieve thermal improvements. Even if that means a new wall in front of what was the Facade or Firebox opening. The back side of this new "interior wall" will still experience the cold of the attic. So although it will not be exposed to moisture from the outside it is being exposed to a vented attic that will not have a plywood deck.
I've yet to identify a carpenter or contractor that is willing to do air sealing details in an attic without the entire remodel being their's. The guys who do so can chose clients in the South County where folks like Prince Harry, Oprah, and Ellen live. Many won't even work with a client that hasn't engaged both an architect and a designer. And yes, I contacted an architect and they seem to have plenty of clients, that are shall we say high-net-worth, with projects that get featured in magazines and online publications. That or more lip-stick oriented remodels. This climate zone is considered mild or Mediterranean so many still just blow hot air to make up for lack of air-sealing details. At forty three cents per kilo watt hour that makes little sense to me. I'm not physically able to spend much time in the attic although I plan to have the insulation vacuumed out to make a nice workspace.