There is a house in S. Ca with chimney separating from the house for around half an inch. We are debating whether to adjust and brace it to the house frame with 1/4" thick, 1-1/2" wide steel bars.
Pro: Minimize vibrations, separations and damages to weather seal.
Con: During earth quake, chimney and house would not be able to move separately. Counter Con: Not much we can do to stop quake damages anyway.
What are your opinions?
Is it brick? It will disassemble in a good quake. Ours did in '89.
-- John Larkin Highland Technology, Inc jlarkin at highlandtechnology dot com http://www.highlandtechnology.com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom laser drivers and controllers Photonics and fiberoptic TTL data links VME thermocouple, LVDT, synchro acquisition and simulation
Yes, it is. But at least it will look better until then. The weather seal won't hold without stopping the separations.
Strapping a brick chimney to a wood frame house in order to hold it? Hopefully that won't result in some frame twisting, where suddenly a bathroom window becomes sticky, then some door won't open anymore, et cetera.
My gut feel is that the chimney foundation is not alright or maybe you had some water damage down in there. Probably needs to be shored up.
-- Regards, Joerg http://www.analogconsultants.com/
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Or strapping a wood frame house to a brick chimney.
The chimney seems OK. Perhaps the house is settling a bit. Anyway, we just need to minimize the separations.
Then one sunny day ...
That should be easy to find out with a plumb-bob :-)
Or fill them in?
-- Regards, Joerg http://www.analogconsultants.com/
I keep thinking roof, but I can't picture the situation without looking at a picture. One story ?
Greg
It usually looks like this, but the only real fix I can think of is foundation repair:
The scariest story came from a guy (engineer!) who had his fireplace along with lots of bricks from the chimney fly out by several inches in a earthquake out here. "So what did you do?" ... "Oh, I just pushed it all back in there".
-- Regards, Joerg http://www.analogconsultants.com/
Adhesive caulk and aluminium angle flashing. Get an adhesive caulk that is flexible for small movements. Take a look at Lexel Caulk (Google). Lexel seals and sticks Al to anything but is not structural, i.e. chimney and house are still independent. Lexel even sticks polycarbonate (Lexan). Nail and Lexel Al to house and Lexel to chimney. I have used it and it is still holding after 10 years.
t
Two stories. The homeowner opened up the dry wall from the second floor inside. On one side, we can see a 1/2 inch gap from the external stucco. The house and/or chimney is leaning side-way. It might not be a big problem, but the homeowner does not want the leaning tower next to the house. We are thinking about one brace attached to the floor joist beam (between the two stories) and one up high near the roof. Hopefully, we can pull the house and chimney back into position, or at least stop it from separating further.
Obviously, it wasn't always like that. So, which moved? The house or the chimney base? Check with a laser level or plumb line.
The problem is that if you close the gap between the chimney and the house by brute force, you're likely to either crack the bricks, the mortar holding the bricks, or tear the house apart.
I helped a friend fix almost exactly the same problem caused by ground subsidence. In this case, the brick chimney was leaning about 3 degrees away from the house. We excavated two big trenches on either side of the chimney base, and horizontal drilled under the base on the side towards the house, using plenty of water. The weight of the chimney and base closed the gap with the house after about 3 weeks. We then refilled the holes and used a ground pounder to pack the dirt to prevent further settling. This is not exactly the standard procedure, but it worked well enough.
That will almost surely track the brick or mortar. Brick and mortar work nicely in compression. However, the bracing will apply tension which will cause the brick and mortar to separate. Worse, it will do it at a one point (near the bars), which will create a nifty stress riser at the point of contact.
In 1989, we had a 7.1 quake in the area. I live in the mountains, where most everyone had a brick or rock chimney for wood heating. On my hillside, there was exactly one brick chimney left standing. Upon investigation, I found that the original builder had lined the flue with a 10" steel pipe with about 1/8" wall thickness. Nothing is going to bend or break that chimney although it might take a cord of wood to get it hot enough to draw.
Much of the falling masonry landed on the roofs of the various houses, causing considerable roof damage. Same with a few vehicles that were parked next to the chimney. In my never humble opinion, the correct answer is to NOT use brick. Use Metalbestos or triple wall flue pipe for the core of the chimney, and then frame it in with wood siding. Because it is light weight, it won't need much of concrete base. 0.5" separation in what I guess might be 18ft, implies that you have a damaged or sinking chimney base, probably due to improper foundation construction, underground water, or tree roots. You may also have cracks in your foundation if it's a slab or continuous perimeter block wall. A plumb line test will tell all. If either or both conditions are present, then you're looking at reducing the ground loading to prevent further settling and/or cracking. That means a light weight chimney which precludes any use of heavy brick.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Settling is way more likely. The other option is to get rid of the fireplace. Or if you really think you need one, put in a gas fireplace. They just need a flue pipe. The "chimney" itself is just stucco.
There are a lot of good reasons to get rid of a masonry fireplace. First, depending where you live, there are spare the air days. You can't always use your fireplace. Second, burning wood is pollution. Now I have no problem with a campfire in the boonies, but you can't have a lot of burning in urban areas. Third, firewood is a common way to bring wood eating bugs into your house. Fourth, well you already know it. They suck in earthquakes. Sometimes with fatal results.
I'm not promising this will improve your sex life...but well..
Nobody uses logs anymore. They just have the fire pop up from rocks. Really very cool.
No, it is not. The problem with wood burning is that most people do it wrong. And instead of educating people the leftists just ban everything. Not in our county though.
We heat with wood almost exclusively. When the wood stove operates there is no smoke crawling out of the chimney and the (EPA certified) stove is under 2 grams of particulate matter per hour even at full bore. In fact, when cleaning the pellet stove vent I once burned myself on the wood stove pipe storm cap once. I forgot that it was running and there was no smell even while standing right next to it on the roof. Environmentally it is one of the best methods as it is almost carbon neutral. A gas fireplace is not.
Have you forgotten all the people who died after earthquakes because gas lines ruptured and the gas ignited?
That's for yuppies :-)
A real wood buring stove looks like ours:
-- Regards, Joerg http://www.analogconsultants.com/
They don't really use the fireplace, since it never snows (they lie, it rains) in Southern California. However, they like the look of brick fireplace and chimney. Perhaps, we can cut a thin layer of brick for the surface, rather than stucco. I guess we have to tear down the existing chimney.
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the limit for a euro5 diesel car is 5mg/km ....
-Lasse
You should calculate the weight of the chimney. Its a lot, I think Johns right that it might just pull the house with it.
Cheers
"Starting at $2,851". Ouch.
You're making me feeling guilty that my 30 year old wood burner doesn't have a proper afterburner, turbo charger, catalytic converter, smog certificate, etc. A replacement is on my list of things to buy after I win the lottery: Yes, mine belches smoke if I burn a green wood mix or misadjust the air intake. Otherwise, it's tolerably clean, but nowhere near your
2g/hr. Phase II EPA limits are 7.5 grams of smoke per hour for noncatalytic stoves and 4.1 grams per hour for catalytic stoves. Mine is nowhere close to that although it's an improvement over the abomination that came with the house in about 1973: I gave it away to someone that's using it as a hot tub water heater.I just happen to be talking to a realtor on the phone. She guessed that a gas fireplace will add $10,000 to the value of the house. A functional wood burner might add a bit more. A cracked chimney or defective flue pipe will drop the value about $10,000. She also indicated that it is difficult to sell a house without some manner of fireplace as buyers usually consider it a mandatory requirement.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Local code is to only use small "L" brackets between the brickwork and the house and to leave a 1"(?) air gap between the chimney and the house to prevent burning down the house from fire leaking through cracks in the masonry or mortar. There's no intention to securely tie the house to the chimney. The major purpose of the clips is to prevent the wind from blowing over the chimney. The clips will also raise the resonant frequency of the chimney in the event of an earthquake, which hopefully will help prevent total collapse. I don't recall the requirements for the footer base. As I vaguely recall and am too lazy to research, if it's a slab foundation, the chimney pad COULD be part of the main foundation. If it's a continuous perimeter foundation (inverted T), the chimney footer is probably isolated, making the chimney almost free standing, except for the wind bracing:
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
So it spews out the same in as little as 400km. That's not very good, considering that the particulate matter will be drifting onto sidewalks with babies in strollers, instead of a rood and backyard like here. Maybe that is why they have such a hard time getting Diesels certified in California. I think right now only one Volkswagen TDI engine is.
-- Regards, Joerg http://www.analogconsultants.com/
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kThe clips would prevent movements from breaking the weather seal from wind and/or small quakes.
But it could also cause more damages to the house. However, beyond a certain victor scale, nothing matter much anyway.
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