# Chimney Cap & Repointing Report



## superseal (Feb 4, 2009)

I'll tell you this,...you're a terribly well spoken person  and I admire that.

Back to the chimney,...Is that a solid concrete crown? or did you parge over the top course?

The no penetration flue is a no no, I shoot for 6" and you'll need 5" additional for any top cover...

No overhang, drip :blink: a no no also.

I would of ripped off the top courses and re- configured for a standard 4" skirt /e.g. SS chase cover.

That crown should be floating on that chimney if it is concrete, otherwise it will all crack up in no time :sad: I always use stucco tape for perimeter bond break and infill with a little sand.

And that mud does look quite Portland rich.


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## yourfriend (Aug 16, 2013)

superseal said:


> I'll tell you this,...you're a terribly well spoken person  and I admire that.
> 
> Back to the chimney,...Is that a solid concrete crown? or did you parge over the top course?
> 
> ...


Superseal, thanks for the kind remarks. My parents insisted I go to school and learn to like it and learning. Can you imagine that?

Originally, the chimney was topped with a flat concrete crown that was maybe 2-3?" thick and stopped a few inches short from the edge of the top course of brick with a bond-break separation below it. 70 years of age showed on its condition. The surface was pretty rough and there were a few cracks, not many but a few. I'm told it likely had rebar somewhere inside. The current, unreinforced solid concrete cap was formed over the old cap and it is attached to it and the other masonry rather than floating above on a separation layer.

If, as you say, that direct adhesion means the crown will crack--or do that deed to the engaged brickwork--maybe the time to get after it with some sawing is now before it has stubbornly cured. Maybe. Were that both feasible and advisable, my bet is I could
fabricate a dandy one with your guidance.

I'm happy to be the hands for your brains. If you gentlemen discuss to a consensus approach here, I'm ten fingers at your community service. I think one thing that would be soonest lamented would be neglecting to undertake a measure now that would be more difficult or regretted later. 

Please let me say that I understand it would be easy for the attention of any of you to tire of this matter. Yet, if I can ask you to persist with your insights until we can chart the best of possibilities, persistence in resolving a hard problem will affirm your expertise, my gratitude will have an elephant's memory and Mom's house will have an OK chimney.


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## dakzaag (Jan 6, 2009)

I have been subscribing to this repair from the previous thread thru this one, allow me to express a few opinions.
A. Pictures are worth a thousand words...nuff said.

B. The pointing mix looks to be pretty strong Portland, I fear for the chimney's life more because of the pointing mix then the Cap. In my not so humble opinion, you should have stuck to the Virginia Lime angle of your investigation.:whistling

C. Cap has an existing bond break, a nice overhang/drip edge, and is thick enough to withstand a beating or two before giving it up. I would not touch it until you see major cracks allowing water into the chimney. If you inspect it every fall you will most likely observe 10 good years of performance before serious decay sets in. 

Yes, the liner should extend up further. Yes, you could spend a bunch of money on a SS cap that could cover everything. Yes, a few details of the crown and liner could have been addressed with the recent repair, but unfortunately they were not.

Concrete comes in two flavors. Cracked and Gonna Crack. You have the Gonna Crack flavor, so when it becomes cracked then you will have to see what remediation is available at that time. 

In the mean time schedule some other pressing maintenance and just eye ball the chimney every six months or so and I think you will be pleasantly surprised.


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## yourfriend (Aug 16, 2013)

dakzaag said:


> I have been subscribing to this repair from the previous thread thru this one, allow me to express a few opinions.
> A. Pictures are worth a thousand words...nuff said.
> 
> B. The pointing mix looks to be pretty strong Portland, I fear for the chimney's life more because of the pointing mix then the Cap. In my not so humble opinion, you should have stuck to the Virginia Lime angle of your investigation.:whistling
> ...




The only known bond break this new cap may likely have is where it lies atop the smaller old cap that definitely owned an original bond break. Since this new concrete cap may shrink back from the brickwork it extended to beyond the old cap or not bond well to the old cap itself, the possibility that there may be an irregular attachment in some of those areas must be admitted. 

I'll inspect on the new cap perimeter tomorrow. Maybe more wetting would help the new cap get some edge separation if it isn't already in evidence. That is an idea unless people think it a suggestion.

The photos depict the new cap feathering to the edge of the top row of corbelled bricks. Photos the other gentlemen have introduced of results I envy show that their caps extend 1.5-2" out beyond the brickwork into free space before they are defined as having a drip edge.

I told the mason to use high-lime Type O commended in the first posting on the chimney. He brought the separately bagged ingredients to the job to mix that.

Quite evidently, the group's veteran eyes are focusing on what the mason did use as being Type S or something similar, directly contrary to my wishes, instructions and pointed reference to several supportive sources, including the informative exchange we had on the topic. 

Oh well. Calling him names isn't going to make the result go away or drive me back to grinding and chiseling. There, we agree, is work I'm leaving alone.

As to letting this sleeping dog of a cap lie until it smells and looks bad enough to demand disposal...that is a point for consideration and it may be a runner in the field of other alternatives. Whether that will inspire anyone to argue that leaving the new cap there is a worse alternative remains to be seen.

Thank you kindly for staying with this case. All opinions are welcome in the discussion.


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## yourfriend (Aug 16, 2013)

Here is a thank-you reference you folks may find useful in discussions with clients:
http://inspectapedia.com/chimneys/Chimney_Caps_Tops.php#CrackedTop
Plenty of pictures and plenty of good, concise links.

Now, back to the scene of the crime in this thread....


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## JBM (Mar 31, 2011)

I really couldnt follow this much, but that brick looks like these 











The brick doesnt look antique or very old at all. Since there is a flue I highly doubt that chimney was built before 1940, although what do I know. 

You should simply have your mason back and add a 5" piece of flue, mix some portland with some milk in it and cement it in with some sort of bevel to run water away and to hold it in place.

Other then that you are expending way to much energy on a chimney that could just be knocked off the roof and rebuilt in a day.


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## dakzaag (Jan 6, 2009)

We cannot be certain from a picture what that mortar is. Visually from the pictures supplied, it appears to be typical Masonry Cement. (I am not aware of a visual difference from N to S.) I doubt the mason ignored your request to make a Type O, but my experience would suggest that Type O would appear just like the picture. A historic Lime mortar has no Portland whatsoever. 

The corbelled brick and cement wash make up the chimney crown with drip edge. It would be considered a protective appliance that is replaceable when the weather eventually decay's it. The old bond break is the new bond break except for the edge which has none. I will often trim my bond break/flashing back from the edge to eliminate gaps and ripples at the junction of the wash and brick if it is flush. While this is not an ideal detail, it is often preferable to having a small gap that the customer assumes will need maintenance.

Superseal's picture of a crown that overhangs the chimney is the ideal design for longevity of a chimney crown. Not all customers like the look, I have installed many crowns that look a lot like your existing one. I have never seen a cement crown shrink and pull back from the edges, but poorly designed ones will crack and allow moisture to penetrate. Maybe I just don't see enough failures to observe this shrinkage. I think shrinkage would happen in the first three day's of curing typically.

You will always have the option to install a metal cap of your choice alloy in the future as needed.


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## yourfriend (Aug 16, 2013)

JBM said:


> I really couldnt follow this much, but that brick looks like these
> 
> 
> 
> ...



>> The house was built in the 1941-3 period, which should date the Higgins' Brick to that time.

I hear you on the flue issue and will deal with it eventually. Now,
my concern is to deal with immediate problems. 

Should the tide of opinion be to leave things be until problems announce themselves more severely, I'll comply.

***I do have a crack (now hairline to 1/64") that runs across the upper edge of the shoulder bricks where they meet the wide mortar band which slopes into the chimney stack. Is that something I should deal with now? If so, how?

Thanks.


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## yourfriend (Aug 16, 2013)

Cleaning the Chimney Exterior.



It has been 8 days since operations ended. Is now the time to get after the mortar haze and some drippings on the brick faces? What procedures and cleaners would you use?


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## fjn (Aug 17, 2011)

This stuff. http://www.northeastnursery.com/files/VanaTrol.pdf


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## JBM (Mar 31, 2011)

I do not believe that extruded bricks were available in 1943. Im not exactly the history buff, I just lay em, but that is imo an extruded brick you have on that chimney. Ive never seen a molded brick with sharp lines like that. If that is the case it could have been rebuilt at some point already.


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## JBM (Mar 31, 2011)

Apparently exctruded bricks have been around for a lot longer then that. Although the bricks on that chimney appear to be more recent than 1943 to me.


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## dom-mas (Nov 26, 2011)

JBM said:


> I do not believe that extruded bricks were available in 1943. Im not exactly the history buff, I just lay em, but that is imo an extruded brick you have on that chimney. Ive never seen a molded brick with sharp lines like that. If that is the case it could have been rebuilt at some point already.


Extruded brick were available from the 30's on. (I think different areas different technologies). i don't see where you see a flue, unless you mean a brick flue. in that case I've seen brick flues in all the chimney's I've worked on from the 1890's-1940's until flue liners became common


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## yourfriend (Aug 16, 2013)

JBM said:


> I do not believe that extruded bricks were available in 1943. Im not exactly the history buff, I just lay em, but that is imo an extruded brick you have on that chimney. Ive never seen a molded brick with sharp lines like that. If that is the case it could have been rebuilt at some point already.


The flurry of inquiries made did somehow bring me in contact with a
descendant of the Higgins clan. His thought was that the brick was
"medium" on a hardness scale. 

That opinion was the upper outlier against other reports from trade workers that the bricks were softer than that and came with the qualification that he had no manual experience with bricklaying. I didn't bring up the manufacturing issue of extrusion vs. molding.

All I know is that the Higgins Brick operation had plenty of local operations and, at least in their last stages, was no laggard in adopting new technology.

**On the mortar shoulder crack observed along the brick line, I'm going to let that be unless told not to.

JBM, thank you.


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## dom-mas (Nov 26, 2011)

Only because you are in southern california, and you will get no freeze thaw I say don't worry about it. But maybe dbrons will say different, or Tscar, or stacker, or Kniggit who are all in southern arid areas (at least I think Okla is southern and arid, my US geography isn't great)


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## yourfriend (Aug 16, 2013)

dom-mas said:


> Only because you are in southern california, and you will get no freeze thaw I say don't worry about it. But maybe dbrons will say different, or Tscar, or stacker, or Kniggit who are all in southern arid areas (at least I think Okla is southern and arid, my US geography isn't great)


Dom-mas:

"Freeze thaw" here would be a freakish happening. If it has occured in my decades here, the recollection has escaped me. 

**There is an approximately 1.5" long X 1/16" area of shrinkage in the wide shoulder band of mortar where it meets the stucco wall and interfaces with the chimney stack I should have mentioned. Maybe those gentleman will also have thoughts on whether that is a wise repair. I do have a bag of rapid-set cement and Type S on hand if either would work without problem in that small area.

I also have some sand and Portland Type II here and can buy a bag of lime if the O mix we may or may not have in the mortar needs to be used as a repair material either in that last-named area or elsewhere.


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## JBM (Mar 31, 2011)

Oh I didnt look close enough to notice that it was a brick flue. Cool. 

anyhow, with regards to if a brick is hard or not, it really should be weighed with how much weight the brick is responsible for supporting. In this situation the bricks arnt asked to support much weight considering.


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## yourfriend (Aug 16, 2013)

JBM said:


> Oh I didnt look close enough to notice that it was a brick flue. Cool.
> 
> anyhow, with regards to if a brick is hard or not, it really should be weighed with how much weight the brick is responsible for supporting. In this situation the bricks arnt asked to support much weight considering.


"Cool" made me laugh. Our senses of humor aren't at odds.

Except for the part of the stack that went over the roof, our quakes didn't hurt the chimney much. Should geology bring the next big one close and trigger the soil fluction to which this area is disposed, the chimney will be a nonexistent worry only because it will be gone.

**Now, let's hope advice weighs in on the crack at the top of the shoulder mortar interface with the stack and the hairline crack running along the top width of the bricks in the shoulder as described in posts above. What a necessary or serviceable patching material would be interests me.


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## JBM (Mar 31, 2011)

You could brush on some thoroseal, it is like masonry windex, good for a million uses.


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## Tom M (Jan 3, 2007)

I have a questions. I can never find a mason willing to build a crown nor can I buy one premade.

We have many typical size chimneys' with single 8.5x8.5 flues. I think a 24"x24" crown would handle many of the chimneys I encounter. Nearly all of them only have mortar washes.
1. If I built one on the ground, how heavy might it be?
2.Do I have concoct my own mixture? I know a Lime mix is most flexible but isnt a premixed type "N" mix more flexible than a type "S"?
3. I thought crowns crack from flue expansion why do we need to float these crown? Gravity only seems like an uplift concern.

Sorry for the silly questions Im not a mason. I doubt I would be getting into a new specialty but with so many similar chimenys in the area maybe I can accomadate some with a premade crown.


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