Best Course of Action (old chimney rebuild)

[Amateur_Expert]

Hi everyone,

I have looked and looked and cannot find info on the best route, or path, to take when re-mortar entire chimney.

My question is do you start at the top or bottom? Do you do one side first or progress around in a spiral from side to side??

This chimney is COMPLETELY shot. The bricks seems fine but the mortar is dust. I am talking you have to file your fingernail after chipping out the mortar.. heck you don't even need a fingernail! I have never seen mortar this bad, it's like powder. For the life of me I cannot understand how it is holding itself up frankly.You notice the hole in the side, this adds to my bewilderment of how this thing has not collapsed! I plan to use the hole as a starting point.

As mentioned the mortar is just unbelieveably brittle. I foresee no problem whatsoever about chipping it away. My only question is which direction should I go?

Hypothetically, will 3 sides hold up the chimney? If so maybe I can start with one side and complete one side first. Someone also suggested I work around from side to side from the bottom, thus making it stronger as I get to the top. Another person suggested shoring it up with plywood first.

I really don't know where to start other than fixing the hole.House built in 1922 in Kansas. I gotta say I cannot explain how it has not been toppled by wind.This really has me concerned. I know without even asking that it would cost $1000's of dollars to have repaired and this is not an option. I am pretty handy and have the tools.

One concern I have it that if I start at the bottom the weight would be a factor. Or should I start at the hole and work both directions on that single side?

Any help greatly appreciated.

Thanks!

PS It has a slight lean but I was told that they were built that way sometimes b/c the base of the chimney wasn't always even with the hole in the roof.

Shawn
Wichita KS

 

[begreen]

Greetings. I'm not sure if you can save it other than pouring in a liner to stabilize the whole thing. Our chimney and fireplace was in similar shape. It was built around 1924 and the mortar was dust. A couple good earthquakes made it ever riskier. There was no clay liner and only luck was holding it together. I pulled the whole think down in a day with my son helping me. It's a good thing I did. That exposed even more scary stuff like old stove takeoff that had just been plastered over. One had wood right up against the plug!

What is the chimney currently used for? If planning for future use, have you considered replacing it with a good new metal chimney? That would be my first and second choice. You could do this yourself in a weekend.

 

[Amateur_Expert]

Greetings. I'm not sure if you can save it other than pouring in a liner to stabilize the whole thing. Our chimney and fireplace was in similar shape. It was built around 1924 and the mortar was dust. A couple good earthquakes made it ever riskier. There was no clay liner and only luck was holding it together. I pulled the whole think down in a day with my son helping me. It's a good thing I did. That exposed even more scary stuff like old stove takeoff that had just been plastered over. One had wood right up against the plug!

What is the chimney currently used for? If planning for future use, have you considered replacing it with a good new metal chimney? That would be my first and second choice. You could do this yourself in a weekend.

Thanks much for the reply and for sharing your experience.. I bet you had a "job well done feeling" after pulling yours down!

A liner you say? You can pour those?? Had not seen that, only familiar with like the stainless pipe "liner" that you can insert (which is my plan in the end).

What is the plug?

The pic below shows the bottom (chimney not visible but it's behind sheetrock above the opening in a closet) the brick just ends at the wood and boarded under.

I am not sure what it all had and need to familiarize myself with some of the terms, like "firebox" for example. I expect the base will need to be constructed from scratch perhaps. I want to hook a wood stove up to it in the end.

It has no liner, just straight brick.

Metal Chimney you say? Is this straight 6" pipe from floor to roof and above?? Had not really considered that, sort of wanted to just repair the chimney so I could avoid the permit process of removing AND re-constructing.

Shawn

 

[begreen]

The permitting process will depend on your local bldg and fire dept. rules. I expect your insurance company would like a metal, class A chimney the best. This would be class A pipe from the stove room ceiling all the way out to the sky. It would need a ceiling support box at the bottom, then a simple firestop as it penetrates the next ceiling. In the attic it gets an attic insulation guard, then up through the roof. Looks like you would need a roof peak flashing which I think Security still makes? This would be the safest install.

There are also companies that will run a 6", full length chimney "balloon" down the chimney, center it, then pour a mix of cement and insulator down around the balloon. Once this sets up you have a reliable chimney core. The all the chimney crack mortar still would need full pointing.

A metal liner will work, but that will not reinforce the chimney. If you choose this route you will still need to do a good job of repairing the mortar. Unless the chimney has an offset, I would go with a rigid, insulated liner in this case. The chimney must be cleaned first before installing a liner.

http://www.bostonbrick.com/chimney-repair-options/

There are several articles here on Hearth.com about chimneys:
https://www.hearth.com/econtent/index.php/articles/htchimneyup_twostory
https://www.hearth.com/econtent/index.php/articles/reline_masonry_chimney/

 

[bholler]

Honestly from the pics i see it doesn't look that bad. What i would recommend before anything else is get a pro in to scan and inspect it to see if there are any old crocks that are covered and to check it all out. But as long as all that is good i would lay in new brick to patch where that wood is. The it looks like the top probably needs rebuilt from the roof line possibly attic floor up. Then line it with stainless and pour insulation in around the liner. If you are paying for it a class a prefab metal chimney would probably be cheaper. If you are doing it your self you need to go take a masonry class at a local trade school before you attempt this yourself unless you have some decent experience. As far as the soft mortar in the lower part i would just parge over it with fiber bond with that and the liner from what i can see i think you should be ok. But you need to have a pro out to check it in person.

 

[bholler]

If you do feel the need to re point it you would only rake out the old mortar about an inch deep then refill with new mortar. Doing that you can do large sections at a time we usually do the entire chimney then go over it with the new mortar. But if you do that you need to use fairly soft mortar. Type n should be the absolute hardest mortar you should use going harder than that could cause issues

 

[Amateur_Expert]

The permitting process will depend on your local bldg and fire dept. rules. I expect your insurance company would like a metal, class A chimney the best. This would be class A pipe from the stove room ceiling all the way out to the sky. It would need a ceiling support box at the bottom, then a simple firestop as it penetrates the next ceiling. In the attic it gets an attic insulation guard, then up through the roof. Looks like you would need a roof peak flashing which I think Security still makes? This would be the safest install.

There are also companies that will run a 6", full length chimney "balloon" down the chimney, center it, then pour a mix of cement and insulator down around the balloon. Once this sets up you have a reliable chimney core. The all the chimney crack mortar still would need full pointing.

A metal liner will work, but that will not reinforce the chimney. If you choose this route you will still need to do a good job of repairing the mortar. Unless the chimney has an offset, I would go with a rigid, insulated liner in this case. The chimney must be cleaned first before installing a liner.

http://www.bostonbrick.com/chimney-repair-options/

There are several articles here on Hearth.com about chimneys:
https://www.hearth.com/econtent/index.php/articles/htchimneyup_twostory
https://www.hearth.com/econtent/index.php/articles/reline_masonry_chimney/

Hey thanks for the tips and links! This is already been quite a learning experience and I just started researching today.

I have yet to check into fire codes. My insurance agent just said he'd come look at it and he doesn't usually look very hard. Anyhow I never start until I feel confident in doing it right.

I see alot of people doing it with pipe. I initially thought about using the brick but it might be easier to tear out and use metal.

However I want to keep the cost down, cost is the #1 factor. Had a killer set of electric bills this winter then we bought a stove. Summer is my slow season so I am using this time for this.

I had not heard of the pour-in liners, can you get a kit to do this yourself?

The metal liner I mentioned was initially planned not for structural. Yes I would like to reinforce it. If you use a pour-in liner does that eliminate the need for the metal liner?

It looks offset but slight however I thought maybe a flex liner would work.

Those liners can be costly though. I would use a pour-in if I could but wouldn't want to hire it done b/c that would probably be a steep charge.

Thanks again B

Shawn

 

[Amateur_Expert]

Honestly from the pics i see it doesn't look that bad. What i would recommend before anything else is get a pro in to scan and inspect it to see if there are any old crocks that are covered and to check it all out. But as long as all that is good i would lay in new brick to patch where that wood is. The it looks like the top probably needs rebuilt from the roof line possibly attic floor up. Then line it with stainless and pour insulation in around the liner. If you are paying for it a class a prefab metal chimney would probably be cheaper. If you are doing it your self you need to go take a masonry class at a local trade school before you attempt this yourself unless you have some decent experience. As far as the soft mortar in the lower part i would just parge over it with fiber bond with that and the liner from what i can see i think you should be ok. But you need to have a pro out to check it in person.

That's interesting.. could one run a metal liner then pour concrete around that? And then replace the mortar without fear of collapse?
Hey great idea, I will check on classes (but need to keep the cost down). Let me say this, I am not afraid of any project (learned thiscuz dad always had us help with everything, never hired anything done... except roofing. That's the only thing I won't do! Anything else I'll do. I feel confident that I could do it as long as it doesn't fall on me! I plan to remove a few bricks at a time and wire brush them, wet them down, re-butter the brick and lay it on there. I am going to check out a couple youtube videos and as long as I have the right mortar (someone said use a soft mortar) I would feel good about it.

 

[begreen]

This is infrastructure. It is going to be your primary safety barrier in the event of a chimney fire. Whatever the plan of action, do it right and do it safely. Just a guess, from the sounds of things you may be in for about $6-700 in materials.

 

[Amateur_Expert]

If you do feel the need to re point it you would only rake out the old mortar about an inch deep then refill with new mortar. Doing that you can do large sections at a time we usually do the entire chimney then go over it with the new mortar. But if you do that you need to use fairly soft mortar. Type n should be the absolute hardest mortar you should use going harder than that could cause issues

I would like to repoint instead of tearing it out, less cost just lots of labor. You say an inch deep?? I have heard this before.. what about the back half of the brick that still has the old mortar? Is this assuming that you will pour an inside liner?? I like this idea if it would be strong enough.

 

[bholler]

That's interesting.. could one run a metal liner then pour concrete around that?

No you absolutly cannot pour concrete around the liner that would completely destroy your chimney. You need to pour insulation around it which is a mixture of cement and vermiculite. It will help stabilize it a bit.

I feel confident that I could do it as long as it doesn't fall on me! I plan to remove a few bricks at a time and wire brush them, wet them down, re-butter the brick and lay it on there. I am going to check out a couple youtube videos and as long as I have the right mortar (someone said use a soft mortar) I would feel good about it.

You do not want to or need to do that you just need to repoint and as a matter of fact i doubt you even need to do that for most of it unless you like begreen are in an earthquake area.

I had not heard of the pour-in liners, can you get a kit to do this yourself?

No you cant you need to be an authorized installer and then the equipment is $3000 to $5000 and in my opinion the pour in place liners are an inferior product to a stainless liner