Thread: Chimney built this way of shifted?

I did an inspection and thoughts are needed on the attic part of the chimney. It looks to me as if the chimney was built this way because the mortar lines are not cracked and are going with the angle of the chimney. the home was built in 1906. Any thoughts?

Similar Threads:

• middle (3-car) garage wall (column) shifted outward (CMU blocks)
• Gas Built in Ovens
• anybody' seen this tub built
• new built in appliance
• Tex-Mex Built Home

Yes vintage chimney built at an angle that way

This was a relatively common practice.

It's called a Witch's Bend or Witches Bend, old wives tale that it was supposed to keep witches from flying down the chimney.

Corbbeling masonry.
Corbelling is the use of a number of building components, in this case brick units,

Corbelling allows a projection beyond the face of a wall or in this case to divert the masonry chimney in another direction, yet the units remain level and plumb...
Think of corbelling as a form of masonry cantilevers.

It is a long established practice for masonry builders to utilize corbelling techniques on buildings or components of buildings, such as a the building facade, columns, and make the monolithic brick bond pattern approach look rich in design.
Brick of several color or pattern can be added to the corbelling design.


Defects in old masonry.
Look.Look at the mortar head, bed and butt joints. Use a knife or screwdriver to scrape the mortar out of the joints. It it is effortless I recommend calling a mason.

Gees Louise, lag or something effecting the site.
Sorry for the edits.

Corbeling is where the face is built outward while the wall thickness increases, this keeps the center of gravity load back at the wall and keeps it vertical.

Corbeling masonry:
- CORBEL: A shelf or ledge formed by projecting successive courses of masonry out from the face of the wall.
- RACKING: A method entailing stepping back successive courses of masonry.
- - http://www.gobrick.com/Portals/25/do...0Notes/TN2.pdf

See figures showing corbeling:
- http://gobrick.com/Portals/25/docs/T...otes/TN36A.pdf

That chimney which was built at an angle is not corbelled, nor is it racked, albeit racked describes it better than corbelled, it is just constructed as a dangerous angle.

Sorry I did not see the image.
I took Steve Payson verbiage to use as an illusion.
Ops.
My mistake.

I was thinking of an image of a witches bend I once saw .
This is what I referred to as corbelled.
whitches bend.JPG

As for the chimney in the post, I have no idea.

Originally Posted by ROBERT YOUNG

I was thinking of an image of a witches bend I once saw .
This is what I referred to as corbelled.
whitches bend.JPG

Robert,

That is a 'twist of fate'.

Jerry corbelling has been around for thousands of years.
It is an architectural application.

Corbelling can be used in building materials. Think of it like cantilevering with objects.
Bridge or facade columns are corbelled in masonry, brick and stone.

Your reference to corbelling brick masonry walls is good information, although the brick is corbelled and the substrate, CMU, made broader. The corbelling can be achieved with brick bond lock patterns. Here is a simple one step flemish corbelled wall.
flamish corbelling.JPG
When you inspect a home in masonry and there is brick, not concrete used as a window sill at a 15% angle, that is considered a corbbeled brick sill. That is what I was taught anywho...


That is not a fake by the way. It would be a corbeller and racked free standing chimney/element.

Anthony, after 24 hours of thinking about your question I will try to answer from the view point of a self taught and mentored mason, and from a general builder’s perspective.
I am so happy I am inspecting now. I loved the work but the men were hard to take at times.
This is subject to hypothesis by the way. There are a few simple measurements you could take to be sure of the answer.
That being said: At times, when repairing older homes builders are left with a Pandora's box of other trades, poor workmanship, and materials of dissimilar sizes while demolishing then erecting components you dismantled and will rebuild.
See, crossing over into trades while building or repairing is not taught in any school I know of in North America but did hear of one such accredited center for builders through a colleague at INACHI. A school in France. They teach courses in repairing homes, all the trades, builders can deal with when repairing a home.
In North America, it is mostly on the job training. The better the mentor, the better the student has to offer.
I was respectful most times and repaired components, stuck to detentions and materials for that job and remained respectfully, but will not lie, I did take short cuts in my early years.

IMO, I suspect the mason demolished the chimney only realizing that is would be built off plumb when they went to erect the new chimney. I suspect they set offset plumb lines to follow, passed the deck, then plumbed the courses after that.
By the looks of the angle, it would not take them many brick courses to bring the free standing structure back to plumb.
Question, was the home owner notified?
I say this from experience. An exterior chimney that passed through an eave.
I told the home owner the dilemma and about what is required to repair the chimney.
We discussed the options, he had estimates, then decided to allow me to redirect the chimney off plumb.
It was not dangerous, nor the height that tall. <>5' feet or 38 courses to pass the eave completely to get the headwall. Then I used my torpedo and mason level to continue erecting plumb.

There lay the Pandora's box. Not really, but a bridge that should be crossed never the less.
IMO, builder should inform the owner that a carpenter and roofer are required to readjust the roof deck opening to allow the chimney to protrude allowing > 2" on all sides.

I am hypothetically speaking by the way and from personally having run into this type of modification.
Anthony, after thinking about your question for 24 hours I will try to answer as self taught and mentored masons view and general builders perspective.
I hope it helps.
This is subject to hypothesis by the way. There are a few simple measurements you could take to be sure of the answer.

That being said: At times, when repairing older homes builders are left with a Pandora's box of other trades and materials of dissimilar sizes while demolishing then erecting components you dismantled and will rebuild.

Crossing over into trades is not taught in any school I know of in North America but did here of one through a colleague at INACHI. A school in France teaches a coarse in repairing all the trades builders can deal with when repairing a home.
It is mostly on the job training in North America.
I was respectful most times and learnt how to repair components respectfully but will not lie, I did use short cuts in my early years.

IMO, I suspect the masons demolished the chimney only realizing that is would be built off plumb when they went to erect the new chimney. I suspect they set lines to follow until the passed the deck and plumbed the courses after that. By the looks of the angle, it would not take them many brick courses to bring the free standing structure back to plumb.
Was the home owner notified?

I say this from experience. An exterior chimney that passed through an eave.
I told the home owner the dilemma and about what is required to repair the chimney. We discussed the options, he had estimates, then decided to allow me to redirect the chimney off plumb.
It was not dangerous nor the height that tall. >5' feet or 38 courses to pass the eave completely. Then I used my torpedo and mason level to continue erecting plumb.

There lay the Pandora's box. Not really but a bridge that should have been crossed never the less. The builder should have informed the owner that a carpenter and roofer is required to readjust the roof deck opening to allow the chimney to protrude allow >2" on all sides.

I am hypothetically speaking by the way and from personally having run into this type of modification.
I hope that helps some.

Come on guys you are making this to hard. It was common practice to offset the chimney on one side of a wall, say the kitchen for a kitchen wood stove and leave the living room wall flush. then when they got to the attic they made a small correction to make the chimney exit at the ridge. Right or wrong that's just the way they did it up until 75 to 100 years or so ago. As long as the mortar and brick are good I don't see a problem or a solution

- - - Updated - - -

Come on guys you are making this to hard. It was common practice to offset the chimney on one side of a wall, say the kitchen for a kitchen wood stove and leave the living room wall flush. then when they got to the attic they made a small correction to make the chimney exit at the ridge. Right or wrong that's just the way they did it up until 75 to 100 years or so ago. As long as the mortar and brick are good I don't see a problem or a solution

- - - Updated - - -

Come on guys you are making this to hard. It was common practice to offset the chimney on one side of a wall, say the kitchen for a kitchen wood stove and leave the living room wall flush. then when they got to the attic they made a small correction to make the chimney exit at the ridge. Right or wrong that's just the way they did it up until 75 to 100 years or so ago. As long as the mortar and brick are good I don't see a problem or a solution

- - - Updated - - -

Come on guys you are making this to hard. &nbsp;It was common practice to offset the chimney on one side &nbsp;of a wall, say the kitchen for a kitchen wood stove and leave the living room wall flush. &nbsp;then when &nbsp;they got to the attic they made a small correction to make the chimney exit at the ridge. &nbsp;Right or wrong that's just the way they did it up until 75 to 100 years or so ago. &nbsp;As long as the mortar and brick are good I don't see a problem or a solution

- - - Updated - - -

Come on guys you are making this to hard. It was common practice to offset the chimney on one side of a wall, say the kitchen for a kitchen wood stove and leave the living room wall flush. then when they got to the attic they made a small correction to make the chimney exit at the ridge. right or wrong that's just the way they did it up until 75 to 100 years or so ago. As long as the mortar and brick are good I don't see a problem or a solution

Originally Posted by Don Hawley

Come on guys you are making this to hard. It was common practice to offset the chimney on one side of a wall, say the kitchen for a kitchen wood stove and leave the living room wall flush. then when they got to the attic they made a small correction to make the chimney exit at the ridge. Right or wrong that's just the way they did it up until 75 to 100 years or so ago. As long as the mortar and brick are good I don't see a problem or a solution

The simple solution ... especially with a chimney like the one at an angle in the attic ... is to call for a Level II inspection - after which the chimney will likely need to be taken down to the vertical portion and rebuilt.

Because something was done wrong for 100 years or more makes it okay to leave and just accept it? All because it has not exposed its failure YET?

Originally Posted by ROBERT YOUNG

Sorry I did not see the image.
I took Steve Payson verbiage to use as an illusion.
Ops.
My mistake.

I was thinking of an image of a witches bend I once saw .
This is what I referred to as corbelled.

As for the chimney in the post, I have no idea.

Robert, how did my post:

Originally Posted by Steve Payson

It's called a Witch's Bend or Witches Bend, old wives tale that it was supposed to keep witches from flying down the chimney.

Compel you to post this incoherent post:

Originally Posted by ROBERT YOUNG

Corbbeling masonry.
Corbelling is the use of a number of building components, in this case brick units,

Corbelling allows a projection beyond the face of a wall or in this case to divert the masonry chimney in another direction, yet the units remain level and plumb...
Think of corbelling as a form of masonry cantilevers.

It is a long established practice for masonry builders to utilize corbelling techniques on buildings or components of buildings, such as a the building facade, columns, and make the monolithic brick bond pattern approach look rich in design.
Brick of several color or pattern can be added to the corbelling design.

Defects in old masonry.
Look.Look at the mortar head, bed and butt joints. Use a knife or screwdriver to scrape the mortar out of the joints. It it is effortless I recommend calling a mason.

Gees Louise, lag or something effecting the site.
Sorry for the edits.

Originally Posted by Jerry Peck

The simple solution ... especially with a chimney like the one at an angle in the attic ... is to call for a Level II inspection - after which the chimney will likely need to be taken down to the vertical portion and rebuilt.

Because something was done wrong for 100 years or more makes it okay to leave and just accept it? All because it has not exposed its failure YET?

Jerry, while I have the utmost respect for you and the vast amount of knowledge you poses, that is the most ridiculous thing I’ve ever heard (almost).
I mean, if we all inspect using that logic, why don’t we just advise all our clients to just tear down the entire structure and rebuild since the structure hasn’t “exposed its failure YET”?

Originally Posted by Steve Payson

Jerry, while I have the utmost respect for you and the vast amount of knowledge you poses, that is the most ridiculous thing I’ve ever heard (almost).
I mean, if we all inspect using that logic, why don’t we just advise all our clients to just tear down the entire structure and rebuild since the structure hasn’t “exposed its failure YET”?

Steve,

Question: What is the proper way to inspect a chimney, any chimney, during, say, a resale?

Hint: Level II inspection.

I suspect that you would be very surprised what a Level II inspection might find ... and when things are found 'not right' in a chimney, there are two basic solutions: a) block the fireplace and chimney off; b) tear down and rebuild what is not right.

You find that strange advice? When you find an electrical panel with things which are 'not right' - do you: a) ignore the 'not right' stuff; b) recommend it be fixed?

Now apply your thinking to a fireplace and chimney ... do you still find that to be "the most ridiculous thing I’ve ever heard (almost)"?

If you find a roof which is old, rotten, no granules left on the shingles, the shingles curling and falling apart, but ... no signs of leakage inside - do you: a) ignore it say it is okay "All because it has not exposed its failure YET?"; b) call for replacement?

Again, apply your thinking to a fireplace and chimney ... do you still find that to be "the most ridiculous thing I’ve ever heard (almost)"?

Just a few examples for you to compare your thinking to. Please let us all know how you address those examples. Thank you.

Jerry

The other question which needs to be addressed is the state of the roof framing where the chimney exits the roof. The offset has to be supported at the top laterally and if the framing is shot due to water leaks... with all that reflective barrier around the top much is hidden... well, need I say more?

Also no one raise the issue of whether the chimney is lined either with tiles or metal or what the chimney services?

Yup level 2 would be a wise consideration for client to pursue.

If that's a wooden post, as it appears to be, against the right side of the chimney, it looks as though the bricks were laid against it and original construction. The post, set at an angle, would have been used as both a guide and support for the brick.

Document and advise the client as a potential for failure and recommend a Level 2 inspection

If you refer to the illustrations of corbelling in NFPA211, Chapter 7 page 19, you will see corbels can widen or narrow a chimney or they can offset. However, the maximum offset is limited to the centerline of the upper flue not passing the centerline of the wythe wall of the main chimney supporting it. The chimney pictured here, while very common in some areas is well beyond acceptable. It does not have inherent stability. The force of the upper parts is exerting tremendous pressure at the offset to where it will tend to crack open like an oyster. During high winds as the building flexes so, too will this chimney thus opening many small gaps.

As far as how to construct an offset like this, it is nearly impossible using terra cotta flue tiles. You have to make tight joints between tiles using a medium duty non-water soluble refractory cement mixture (which no masons use) and maintain a 1/2-4" airspace around the flue tiles. Pretty hard to do on a long offset. The worst is cutting the bottom tile on an angle so it mates properly with the top regular tile. When you cut a tile on an angle, the end is not a nominal 5/8" but about an inch or more. This means one edge or the other will not fit flush with the inside face of the flue as required.

The solution for this chimney might be to raze it to the attic floor level then, if the lower chimney passes the level II inspection, use a factory chimney with a masonry adapter plate then support the offset with straps. That is, if you can size it properly.

Here is page 19 online: http://www.nfpa.org/codes-and-standa...=code&code=211

HTH

As far as how to construct an offset like this, it is nearly impossible using terra cotta flue tiles.

Liners are cylinders. Plumb and stationary.
The bricks are laid corbeled and racked like a spiral staircase.

From the link Bob provided:

For your interests

http://inspectapedia.com/chimneys/Ch..._Diagnosis.php

Like I said...

To prevent cracks in a leaned-brick chimney such as this one, the chimney depends on absolutely stable support by the roof framing structure where it passes through the roof to outside. Unless the brick chimney was adequately supported and constructed it may lean, causing the crack pattern we show at above right.

Originally Posted by Raymond Wand

For your interests

http://inspectapedia.com/chimneys/Ch..._Diagnosis.php

Like I said...

Raymond,

I am sure you noticed the bowing of that offset chimney in that link ... I am, of course, presuming that the board used for support of that offset chimney was originally straight, as one would logically think it would be.

If the offset chimney was in fact 'self-supporting', there would not have been any load placed against that supporting board which would cause that board to bow.

Verification that the chimney is, indeed, not 'self-supporting'.

Jerry,

I did not even see the board! It is certainly not self supporting.
Thanks for pointing it out.

Btw did you see the the piece of lumber on the right of the chimney in the original post? To me it has a slight bow to the right. Hard to tell I didn't rotate the picture. Board may have been placed to run/fasten wire up chimney rather than support?

Originally Posted by Raymond Wand

Btw did you see the the piece of lumber on the right of the chimney in the original post? To me it has a slight bow to the right. Hard to tell I didn't rotate the picture. Board may have been placed to run/fasten wire up chimney rather than support?

The chimney in the original post is actually pretty straight (not plumb, but 'straight').

I suspect that board, if original, and it looks to be original, may have just been used as a guide to lay that chimney up in a straight line (not sure, but it could have been). This board is not as large in size (at least it looks smaller in the photo, could be an optical illusion) than the board in the other photo, yet this looks 'straight' while the other one looks 'bowed'.

I've put both here for a side-by-side comparison. Notice that the chimney which as the greater angle is the one which is bowed.

I went back to the two photos and drew a plumb line at the center of the bottom of the chimney up, and a center line from near the top down, to show the offset difference.

The chimney which is offset less (closer to plumb) is not too far over what is permitted offset - but it is still over what is permitted. The one which is bowed is way over the permitted offset - likely the cause for the bowing.

Attachment 32329Attachment 32330

with edit - I replaced the photos and now an extra link is in the post - the first photos only had center plumb lines from the bottom up, these photos also have a center plumb line from the top down

In hopes of not mixing up the thread.
The Inspectapedia image, for what it is worth, is poor building practice.
No argument from me.


In hopes of making myself understood, fat chance of that, ha ha ha, the pic of the chimney below is what I was/ & am now referring to.
corbelled chimney.JPG


7.1.1 Support
7.1.1.1 Masonry chimneys shall be supported on properly design foundations of masonry or reinforce Portland or refractory cement concrete or on noncombustible material having a fire resistance rating of not less than three hours.
7.1.1.2 Such supports shall be independent of the building construction, and the load transferred to the ground.

Now if my term free standing is incorrect please excuse me.

The verb corbelled is used to describes the brick laying technique.
The chimney is not corbelled to transfer load in another direction.

Thanks, that illustrates it well.

I am happy you understood.
Now what the heck did I just say? Ha ha ha

Originally Posted by ROBERT YOUNG

As far as how to construct an offset like this, it is nearly impossible using terra cotta flue tiles.

Liners are cylinders. Plumb and stationary.
The bricks are laid corbeled and racked like a spiral staircase.

The liners in the twisted chimney must be cylindrical because you cannot rotate rectilinear liners as they would leave huge gaps. I'm referring to the slanted chimney provided by the OP. You can NOT cut flue tiles on an angle and have the edges still mate up with straight sections. You can NOT install flue tiles on a slant and reliably maintain the requisite air space.

Very seldom do I find all the flue tiles plumb, in column with proper tight fitting narrow joints laid in code approved mortar.

Two fun pics attached

Thanks for the lines Jerry, they certainly make it very clear the difference in the lean of the two chimneys.

Originally Posted by Bob Harper

The liners in the twisted chimney must be cylindrical because you cannot rotate rectilinear liners as they would leave huge gaps. I'm referring to the slanted chimney provided by the OP. You can NOT cut flue tiles on an angle and have the edges still mate up with straight sections. You can NOT install flue tiles on a slant and reliably maintain the requisite air space.

Very seldom do I find all the flue tiles plumb, in column with proper tight fitting narrow joints laid in code approved mortar.

Two fun pics attached

Surely Bob, only the first and last flue tile would require an angle cut. The others, in between, would simply sit atop of each other, following the angle of the chimney under construction. I'm not sure that maintaining an airspace, when this home was built, was of paramount importance to the mason.
My early childhood, Victorian home, had an angled chimney, much like in the second pic, albeit on the outside of the house and not running through the attic. No problem with draft or leakage as I recall.

Originally Posted by Bob Harper

The liners in the twisted chimney must be cylindrical because you cannot rotate rectilinear liners as they would leave huge gaps. I'm referring to the slanted chimney provided by the OP. You can NOT cut flue tiles on an angle and have the edges still mate up with straight sections. You can NOT install flue tiles on a slant and reliably maintain the requisite air space.

Very seldom do I find all the flue tiles plumb, in column with proper tight fitting narrow joints laid in code approved mortar.

Two fun pics attached

Love the pic's.
Big thanks from this homie!!!

Bob, not to argue, but I suspect you can cut any object to fit an angel.
Terracotta Cylinders due to there obvious equal radius. I could imagine square than rectangles being a more inconvenient angled/combination miter.

Look at common brick. Brick batts and closures.
http://free-ed.net/free-ed/Resources...g01/?iNum=0704

If there is a mathematical mind, I am sure they will try anything out:-)