central furnace chimney removal
Hi,
I have a 2 storey, 100 year old house (1200 sq ft living space) in zone 7. i have switched to ductless heat pumps and have stopped using my oil boiler for heat. The mason chimney goes from the unfinished basement up through the center of the house, and up through the unconditioned/insulated attic before exiting the roof.
I’d like to get rid of it, at least down to just below the 1st floor as it inefficienctly transfers heat, and takes up valuable space in a small house.
-I plan on paying a structural engineer to make sure i can do this,
-then will get it removed it as far as i can into the basement,
-will patch hole in roof, at the same time re-shingle the roof (or metal, not sure)
-will patch holes between floors etc.
Any challenges or issues I should be aware of?
Thanks.
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Replies
I just found Joe's related question and responses, so I'm probably good.
https://www.greenbuildingadvisor.com/question/partial-removal-of-chimney-will-i-be-able-to-do-it
How big is the chimney? I am guessing that this can be done without the engineer. The roof and floor have already been framed around the chimney, once it is gone then you will just have to frame in the openings. A competent carpenter should have no problems with this. The chimney itself should not be supporting any structure of your house.
Re-roofing at this time makes a lot of sense.
Do you plan on any back up heat in support of the heat pumps? Zone 7 gets cold, and at very low temps the heat pumps will not be giving much heat.
Nothing should be resting on the chimney, but that's not always the case. If you don't trust yourself to make that determination a structural engineer is a smart choice.
I've removed several chimneys and it's usually quite easy. Often shockingly easy, in a house that age it wouldn't be surprising at all to find you can just pull the bricks off with your hands. In many cases the biggest concern is keeping the chimney from collapsing while you take it apart. Be wary of someone who proposes just whacking at it with a sledgehammer, that's a good way to make a rickety chimney collapse.
The hardest part is containing and cleaning up the mess. The interior is usually full of soot and when you're working inside the house it's hard to contain. The best approach is to take the bricks off one by one and put them in a trash bag, when you get about a dozen put the bag in a box and carry it out to the dumpster. Be wary of anyone who proposes throwing the bricks off the roof onto the lawn. You'll never get all of the pieces of mortar out of your grass, and bricks have an uncanny ability to bounce and hit fragile objects.