Slightly leaning Chimney question

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Grazi57

New Member
Jul 2, 2017
4
PA
Hi everyone, my wife and I recently purchased a home now coming on two years ago... And like with any new house we started work on it from the inside out - Replaced the furnace (Ouch on the wallet), replaced the main sewer pipe running from the 2nd to 1st floor and a few other smaller things.

Now it's the chimney's turn. When we got the house we noticed there was the slightest lean away from the house, almost not noticeable at all. The lean is there, two years on but not significantly changed. What has changed however is the mortar between the bricks has come out and the flashing is massively damaged. Long story short, we had 6 different people come:

The 3 companies wanted to tear it all down and go down 12-14 courses of bricks. Where as the other 3 smaller companies gave options for both. We settled on one guy who wants to do it for $4,500 - Full rebuild and flashing. Or he would ground out the mortar, replace it, and do the flashing for $1,600.

We like the guy, but money is very tight for us. So we wanted to see if any of you have been through this before. I saw a post on here back in 2007 with the same general scenario but that chimney looked in far worse shape an ours lean wise. I will attach photos. Tell me what you guys know/think. Thank you!

PS: when we got the house inspected, he mentioned that the mortar just needed to be replaced, he felt the lean was not significant enough for a full rebuild. But that was 2 years ago.

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From the pics it is hard to say but it really looks like it just needs repointed and recrowned. Mayby a course or teo relaid. But without seeing and feeling it in person it is hard to say
 
Thanks for the reply bholler! We feel that is the direction we are going to go, but more reply's cant hurt. Have a good 4th!
 
It looks like the chimney cap has deteriorated to the point where water is getting into the mortar, freezing, and cracking the mortar. To me it looks like you could redo the chimney cap, re-point the mortar, and then put a sealer on top of the mortar chimney cap. Or put a metal cap over the top of the chimney. The main thing is to keep the water out of the mortar. I would also seal the mortar all the way down after it is re-pointed.
Is the chimney foundation sinking more on one side?
 
If money is an issue, type S mortar is $5 a bag at Home Depot. Flashing and flashing cement are also pretty cheap. Many good tutorials are freely available on all of the above if you have internet access.

I re-capped mine and tuckpointed it for about $20. (Also wrote the date on the cap so I can be depressed at how time flies every time I sweep the flue.)
 
If money is an issue, type S mortar is $5 a bag at Home Depot. Flashing and flashing cement are also pretty cheap. Many good tutorials are freely available on all of the above if you have internet access.

I re-capped mine and tuckpointed it for about $20. (Also wrote the date on the cap so I can be depressed at how time flies every time I sweep the flue.)
You would also need to rent scaffolding. You would need a grinder and diamond blade. To me it looks like that brick should probably have type n at most used on it but again without being there to check the hardness i cant say for sure. Then it should have a poured crown not just a wash crown. And no sealer on any of it at all. Do the masonry right and dont rely on bandaid sealers
 
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And no sealer on any of it at all. Do the masonry right and dont rely on bandaid sealers

Even properly done masonry can benefit greatly from sealers. Who wants their fine masonry work absorbing wind driven rainwater in November right before the big arctic blow happens? Water does a powerful thing called expansion when it freezes and masonry work is not very flexible.

Unless you think properly done masonry work doesn't absorb water?
 
Even properly done masonry can benefit greatly from sealers. Who wants their fine masonry work absorbing wind driven rainwater in November right before the big arctic blow happens? Water does a powerful thing called expansion when it freezes and masonry work is not very flexible.

Unless you think properly done masonry work doesn't absorb water?
No properly done masonry does not absorb enough water to make a difference. If done correctly it sheds water well enough that the water really does not soak in much. I have seen way more problems caused by waterproofing than fixed by it.
 
No properly done masonry does not absorb enough water to make a difference. If done correctly it sheds water well enough that the water really does not soak in much. I have seen way more problems caused by waterproofing than fixed by it.

The purpose of a sealer is not to fix existing problems, it's to prevent future ones!
BTW, only you have referenced "waterproofing" in this thread. The suggestion was to apply a sealer and that's a good idea. I've never heard of a portland cement based sealer referred to as "waterproofing" because a proper sealer is breathable. I've also never heard of a proper sealer causing damage to portland cement based mortars.

It's simply not true (that mortar doesn't absorb enough water to matter). It doesn't take much frozen water to start to fracture portland cement based mortars. While it's true that poorly mixed/applied mortar will absorb even more water, even well done mortar absorbs enough to cause serious damage over time. Breathable sealers reduce moisture intrusion considerably which not only reduces freeze damage but also intrusion of acid rain (acidified from industrial pollution). It doesn't take a Nobel Prize in chemistry to know what acid rain does to portland cement based mortar. This damage from acid rain continually increases waters ability to penetrate and be damaged by freeze/thaw cycles. A breathable sealer greatly reduces the intrusion of acid rain which wreaks havoc over time.

Here in the Pacific Northwest we get enough steady and constant rain to know that water will migrate through good quality 10" thick concrete walls (even when there are no visible cracks). Please don't tell me that "properly done masonry" doesn't absorb enough water to make a difference! That would be like a doctor telling a fat person "One Oreo cookie a day doesn't contain enough calories to make a difference." ;lol
 
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That's simply not true (that mortar doesn't absorb enough water to matter). It doesn't take much frozen water to start to fracture portland cement based mortars. While it's true that poorly mixed/applied mortar will absorb even more water, even well done mortar absorbs enough to cause serious damage over time. Breathable sealers reduce moisture intrusion considerably which not only reduces freeze damage but also intrusion of acid rain (acidified from industrial pollution). It doesn't take a Nobel Prize in chemistry to know what acid rain does to portland cement based mortar. This damage from acid rain continually increases waters ability to penetrate and be damaged by freeze/thaw cycles. A breathable sealer greatly reduces the intrusion of acid rain which wreaks havoc over time.

BTW, only you have referenced "waterproofing" in this thread. The suggestion was to apply a sealer and that's a good idea. I've never heard of a portland cement based sealer referred to as "waterproofing" because a proper sealer is breathable. I've also never heard of a proper sealer causing damage to portland cement based mortars.

Here in the Pacific Northwest we get enough steady and constant rain to know that water will migrate through good quality 10" thick concrete walls (even when there are no visible cracks). Please don't tell me that "properly done masonry" doesn't absorb enough water to make a difference! That would be like a doctor telling a fat person "One Oreo cookie a day doesn't contain enough calories to make a difference." ;lol
Well i have been doing this a long time. And i can tell you that the only chimnys that we put sealer on are ones built with sandstone because it is so pourous. And i can tell you that chimneys that our company did 40 years ago are holding up just fine with no sealer. It may be different in the pacific northwest where you work but the op is from pa where i work and from my experience chimneys here hold up better unsealed. Infact we have plenty of masonry structures that have held up for hundreds of years with no sealer. And yes i know those werent built with portland based mortar. But portland has been used in mortar for close to 100 years here and plenty of those houses are holding up fine without sealers.
 
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And yes water will migrate through masonry if it is not shed away properly. Which is why proper design and construction is important.
 
And yes water will migrate through masonry if it is not shed away properly. Which is why proper design and construction is important.

Water will migrate through masonry if it's not "shed away properly"?

How do you propose to properly shed water away from a brick chimney? Because when it gets in there and freezes, cracking is the result. And small cracks draw more water in and then bigger cracks result.

Brick chimneys are very expensive to build so the fact that it will last 40 years without sealer is not too impressive. And that's a crazy statement that they hold up better without sealer. Breathable sealers are a proven way to reduce damage from acid rain and freeze/thaw cycles.
 
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Water will migrate through masonry if it's not "shed away properly"?

How do you propose to properly shed water away from a brick chimney? Because when it gets in there and freezes, cracking is the result. And small cracks draw more water in and then bigger cracks result.

Brick chimneys are very expensive to build so the fact that it will last 40 years without sealer is not too impressive. And that's a crazy statement that they hold up better without sealer. Breathable sealers are a proven way to reduce damage from acid rain and freeze/thaw cycles.
You shed water away with a proper overhanging crown good mortar joints and proper flashing. It works and it will be working long after that sealer wears out and is no longer effective. I am sorry but in my experience sealers are either a bandaid that covers up the real problem. Or an unnessecary add on. Like i said it may be different in your climate but it is totally unnessecary where i work and the op lives. And how long do the sealers last?

As far as lasting 40 years those chimneys are 40 years old but are no where near the end of their lives and they have had little to no maitenance needed on the exterior in that time. I am sorry we dont have a longer sample pool of our work but there are plenty of chimneys much older still doing fine without sealers. A good poured crown is the key in my eyes. Not a sealer.
 
You shed water away with a proper overhanging crown good mortar joints and proper flashing. It works and it will be working long after that sealer wears out and is no longer effective. I am sorry but in my experience sealers are either a bandaid that covers up the real problem. Or an unnessecary add on. Like i said it may be different in your climate but it is totally unnessecary where i work and the op lives. And how long do the sealers last?

As far as lasting 40 years those chimneys are 40 years old but are no where near the end of their lives and they have had little to no maitenance needed on the exterior in that time. I am sorry we dont have a longer sample pool of our work but there are plenty of chimneys much older still doing fine without sealers. A good poured crown is the key in my eyes. Not a sealer.

Good mortar joints and proper flashing are standard on good masonry work. But an overhanging crown does not protect against wind driven rain (nor does it protect the crown itself). Mortar is naturally porous. A good sealer contains silanes and siloxanes and microscopic particles that penetrate and fill the pores inside the mortar (as well as the bricks themselves). Because the silanes and siloxanes are drawn inside where sunlight cannot reach they will add a measure of protection for the life of the structure. But applying them every 20 years would be even better.

Cars don't need wax either. The mechanicals will wear out long before a quality polyurethane paint job. But, if it's not garaged and you plan to keep it a long time, you will periodically wax it. Masonry work is like this only more so.

I've never lived in PA but it's my understanding that it would not be uncommon to have cold, wet stormy fall weather followed by a hard freeze. I also understand there are a lot of coal fired power plants that contribute to acid rain. Slowing down the absorption of acids will greatly contribute to the life of a masonry structure. Nothing lasts forever but there are ways to keep masonry looking nice for a lot longer and also maintain it's structural integrity with minimal time and expense (compared to the cost of construction). If you think something is successful because it survived 50 or 60 years then you don't need to do anything to quality masonry work. But, if you want it to stay nice as long as possible, it makes good sense to use a quality sealer.
 
If you think something is successful because it survived 50 or 60 years then you don't need to do anything to quality masonry work
Who said anything about 50 or 60 years? A proberly built masonry chimney can last way longer than that without sealer. And to be fair the silanes and siloxanes have only been around for about 50 years so I don't see how you can claim they greatly extend the life of masonry or that they last the life of the structure.
 
In any case thank you guys so much for your responses. The Chimney structure does not appear to be sinking really on either side when I was up there.

There is that small lean, but we are unsure if it because there is damaged brick/lack of mortar or something else.

The foundation seems totally fine - it looks like after around 14 courses from the top of the Chimney it starts to lean a little to the right or away from the house.

One thing to mention - I'm not sure how much of an effect this may have. Is that in the early 1970's when they were putting 476 in (major PA travel route) this house stood on the proposed roads location. They physically picked up the entire house and moved it some 200-300 yards to where it is now. So if that brick was indeed attached at the time of moving - who knows maybe it did something.

But I'm not an expert.
 
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As far as lasting 40 years those chimneys are 40 years old but are no where near the end of their lives and they have had little to no maitenance needed on the exterior in that time. I am sorry we dont have a longer sample pool of our work but there are plenty of chimneys much older still doing fine without sealers. A good poured crown is the key in my eyes. Not a sealer.

How's 140, 280, or 325 years sound? I've owned masonry houses in PA of all these ages, and each has masonry chimneys that are doing quite well. But, for full disclosure, the two older houses had chimneys that were sealed with lime-based stucco, when built.

My current house, which was covered in stucco until 30 years ago, started showing new signs of water damage within 20 years of removing the stucco. In fact, you could see where one wall would get visibly wet on the outside, from the amount of water it soaked up, and some of the stones were cracking and failing. This was the northeast wall, which typically takes the most abuse in our part of PA (check any old house in this area, the windows always rot on that side first).

In this case, I did seal it with a product from PennKote (Pennsealer), and the problem was resolved. No further damage.

Likewise, I previously lived in a village of brick homes, all built 1877 - 1895. Every one of them was losing the faces of their bricks in the 1990's, excepting the few that had been painted. Sealing there also helped to halt the progression of failure, when comparing neighboring houses that were not sealed.

So, if your timeline is 40 or 80 years, maybe there is no difference. But it does seem there are some long-term benefits to sealing, when your desired product lifetime is measured in centuries. Proper crown construction is key, and sealer will never make up for that, but that doesn't mean the sealer has no merit at all.