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Chimney repair: rebuild or repoint?

79K views 33 replies 14 participants last post by  redspeed  
#1 · (Edited)
Hello,

I've got a 1927 bungalow that needs some chimney work, but I'm getting conflicting advice from different masonry contractors. The chimney mortar is badly eroded and you can see what looks like mortar from a previous repointing job popping out in places. In other places, you can't even see the mortar when looking up from the ground level because it is worn away so much. Fortunately, the chimney is fairly massive (it contains two flues) and I think that has given it enough bulk to stay straight despite failing mortar. But it needs attention somewhat urgently.

My problem is that one masonry contractor recommends rebuilding the chimney from the roofline up (same brick) and repointing below the roofline, whereas another contractor recommends repointing instead of rebuilding.

The contractor recommending a rebuild says that repointing is not a good idea because you have to grind away old mortar until you get to good mortar for the repointing to take well. They assert that you'd grind away all the old mortar without finding any that is solid enough to use as a base for repointing, so a rebuild is the way to go. They also pointed out that it has been repointed at least once already and you can see that mortar popping out from moisture getting behind it and freezing. They think all the mortar is just crumbly and has to go.

The contractor advocating a repoint says that if you grind away enough of the old mortar and replace with new, you'll have enough good mortar to hold the chimney up even if the mortar towards the inside of the chimney is not replaced. They say they'll be replacing a very high percentage of the mortar, so the chimney will be very solid and secure. They also said that the most important thing after repairing the chimney is to apply a sealant on the chimney to protect it, reapplying every few years.

Any masonry experts on here who can clear up the confusion? The bid to rebuild the chimney is a good deal more expensive than the bid to repoint, as you would guess. Will either route yield good results, or should I pay more for the rebuild to be on the safe side? I plan to stay in the house a long time, so doing the job right if not extravagantly is my goal. Also, any opinions on applying sealant to the chimney and how frequently it is merited? I did some research and even found some sources saying you shouldn't seal it all. So many opinions it is hard to decide!

Thanks!
 
#2 ·
at least you've only,,,

got 2 :) either will work or neither has the experience to do the job considering you didn't call a back-of-the-truck jackleg mason,,, the only way i'd do it is to L O O K & that's impossible,,, when done, tho, have him coat the entire sys w/silicone siloxane to prevent wtr intrusion - either brush or spray after 30d - we use prosoco.

doubtful you've got old mortar/soft brick so the modern mortars should work well,,, there's NOTHING as good's hands-on eyeball inspections, tho,,, if its any consolation, we repoint'd a cathedral 4 yrs ago ( 2 yr job ) & used the same prosoco,,, yes, it should be done regularly,,, have to repoint my own & replace some slum flashing w/lead step flashing,,, i'll do the same here.
 
#3 ·
A 1927 house has seen alot of weather. You can repoint a chimney only so many times before you need to rebuild. The point at which you make the decision to do one or the other depends on the chimney's condition.
Post some shots of the chimney. Some closeup ,some a bit away.
Ron
 
#4 ·
Thanks Ron and elitecrete for your input. It is hard to judge from the ground level, but it looks like my mortar joints are eroded pretty badly. I've posted a few photos for reference. They were taken in 12/06, so presumably things look a bit worse now. The photos are about 1 MB each, but show a good amount of detail if you view them at full resolution:

From front of house - http://chott.com/house/chimney_front.jpg
From below chimney - http://chott.com/house/chimney_below.jpg
Brick below roofline - http://chott.com/house/chimney_lower.jpg

Do these photos make the repoint/rebuild decision obvious?
 
#6 ·
agree w/scar,,,

we use 4" grinders & diamond 1/4" tuckpoint blades for our work,,, if the brick's old ( soft ), be VERY careful you don't cut into it & cause damage,,, looks like the lime's washed from some jnts leaving only sand,,, still & all, from your pics, i'd repoint if it were my house.

1 more suggestion - we'd caulk the jnt 'tween the house & chimney using backer rod & silicone.
 
#9 ·
chimney repair

It seems to me that the time has come to replace the brick from the roofline up. Have you asked a structural engineer who has expertise in chimneys and brickwork for an opinion? Might be more objective than the chimney company that will make money on it. Here's a good article I found on common chimney repairs. Good luck!
http://www.oldhouseweb.com/stories/Detailed/14852.shtml
 
#10 ·
The mortar is so recessed in the joints as to almost be absent. And it also looks that way below the roof line which is not good. If the mortar left in the joints is soft and crumbly I would rebuild the chimney as far down to the ground as needed. I can't see putting an inch or so of mortar in the joints as a solution that would give the chimney any structural integrity.
Ron
 
#11 ·
im from ireland and have been building houses for the past 22 years and it souds like your chimney has seen better days
and if your going to stay in the house for a very long time yourself then rebuild it
then you will not have to touch it for another hundred years
repointing you could be fixing it again in 5 to 10 years time
 
#12 ·
repoint or rebuild

I also have a home that a chimney inspector said is unstable. He said that the chimney has deteriorating mortar joints from the inside out. The home was built in 1927. He didn't comment on how many times the chimney may have been repointed.

My question: Is repointing an option if the chimney mortar joints are deteriorating from the inside out vs just mortar deterioration on the outside.
 
#13 ·
I also have a home that a chimney inspector said is unstable. He said that the chimney has deteriorating mortar joints from the inside out. The home was built in 1927. He didn't comment on how many times the chimney may have been repointed.

My question: Is repointing an option if the chimney mortar joints are deteriorating from the inside out vs just mortar deterioration on the outside.
If the chimney is deteriorating the way you described, you have structural issues that need to be adressed. You're getting moisture in where it shouldn't get. Possible the chimney cap, severely deteriorated mortar at the top of the structure or failed flashing. Or a combination of these. Replacing the outside mortar will not address this issue.
Getting a chimney specialist in there to inspect it would be the best way to determine what's needed.
Ron
 
#14 ·
We had it inspected by a chimney inspector who said there are deteriorating mortar joints from inside out. He suggested the cause being that the chimney does not have a cap for protection. The problem we are having is with the seller of the house. He is a contractor and is insisting it can be repointed. From what I've read repointing doesn't address issues inside the chimney. Is that correct?

The chimney inspector said that it is unsafe and needs to be rebuilt from the roof flashing up. The house inspector did not comment on specifics of the chimney since we had hired a chimney inspector. The house inspector said that the chimney "gave" when he pushed on it.

Base on this, does anyone think repointing is a viable option?
 
#15 ·
We had it inspected by a chimney inspector who said there are deteriorating mortar joints from inside out. He suggested the cause being that the chimney does not have a cap for protection. The problem we are having is with the seller of the house. He is a contractor and is insisting it can be repointed. From what I've read repointing doesn't address issues inside the chimney. Is that correct?

The chimney inspector said that it is unsafe and needs to be rebuilt from the roof flashing up. The house inspector did not comment on specifics of the chimney since we had hired a chimney inspector. The house inspector said that the chimney "gave" when he pushed on it.

Base on this, does anyone think repointing is a viable option?
No way!
Where did the house inspector push in the chimney when it,"gave"? This issue could go all the way to the ground as the chimney is 82 years old, especially if it never had a cap.
It is fairly common in older houses that the chimney needs to be rebuilt above the roofline.
Does the chimney have a liner? What shape is it in? A masonary chimney with a damaged or missing liner is a liability.
How many flues does it have?
Ron
 
#16 ·
My last house(single story) - 100 years old - the chimney was soft above the roof line. I took it apart & rebuilt it. Below the roof line it was OK & I repointed where it needed it. The new roof was actually higher then the old roof
My chimney had a liner for th eheating system (gas)
That was the only thing it was used for

Repointing will not be enough to increase the strength of the chimney IMO
 
#17 · (Edited)
I'm not sure where the inspector was pushing. I know he was on the roof at the time.

I'm not sure about the number of flues. I need to ask about that.

It doesn't have a liner. Never has, nor does it have a cap. Basicly the chimney is just a liability now. I was quoted $1800 for the liner and $1600 to rebuild w/ capping.

Thanks for your input. I just wanted to make sure I thinking right. The seller is a contractor and I know he probably knows more than I do about these things.
 
#20 ·
I too am having issues with an older chimney. I have an old victorian farmhouse built in the late 1800-early 1900's in the arts and crafts style. The fireplace is in very good condition, and my grandmother burned fires in up until about 20 years ago. I recently inherited the house and have been bringing it back from a state of disrepair. I have consulted 5 different chimney services. Each has told me something different. The first wants over $6,000 to rebuild the entire chimney, damper, ash dump door, and all. The sweep said that the whole thing shifted when he put his ladder against it and that it was unsafe to use. So far he's the only one who has actually gone up on the roof. However, when I checked the other flue in the other chimney that he supposedly cleaned, there was a pile of junk just sitting there when I opened the cleanout door.
Another recommended rebuilding, but said that it was "silly" use a steel liner since when you rebuild it you can build a new clay liner. A third said all that was needed was a little repointing. A fourth said that the liner is definitely cracked (this I believe because he actually used mirrors and climbed into my firebox) but said that he would't get into the job because it was too big for him to handle and stopped there.
From the ground you can actually see a little space between a few of the bricks, but none are missing and they look to be solid- no degredation. I have no idea when they were last serviced. I found a business card stapled to the stairs next to the other chimney in the house dated OCT 1946, so possibly then.
I am looking into possibly installing a wood burning firplace insert to assist in the heating of my home, as the one sweep that I believe- the one who said that the job was too big for him- said that it would be a lot cheaper , that I would still be able to see the fire so my aesthetics would be preserved, and that it would greatly reduce my heating bills, which would be great as where I am in Mass has the most expensive utility supplier in the state.
My question is who to believe, and what exactly should be done for an insert? Is there a way I can tell for myself? I'm leery of building inspectors, having dealt with them at my previous job and having found several of them to be less than trustworthy. The other issue is that I'm frightened that one will find something in my house that will cause us to have to move out or pay exhorbitant amounts in fines or repairs. I know practically nothing about home owning, as I stated previously I inherited this house from my grandparents, and I don't want to get taken to the cleaners. If anyone can offer some sound advice or has experence, I would appreciate it immensely. Thank you in advance.
 
#21 · (Edited)
Nobody on the internet can tell you who to believe as we haven't seen the chimney.
Is there a way for you to to tell? Sure. Look into the base and see if the liner is indeed cracked. Just because he looked at it with mirrors doesn't mean it's true. If the chimney did indeed "move" when someone put a ladder on it, there's a serious problem. This is easily checked out.
There are many chimney companies that are down right thieves and liars. If you can't discern the chimney's condition be doing an exanimation of it, I would call in a mason not affiliated with any chimney company and get his opinion.
I find it odd that with all the guys you had there, that there was no diagnostic repair continuity.
Ron
 
#22 ·
Ron6519,
Thanks for replying. Sorry I rambled on so much, I am just very confused and emotionally charged right now, and I dislike dealing with people who are not forthright. This has been ongoing since March. I've actually climbed into my firebox myself to look and see what was going on, and the flue is indeed cracked- pretty badly from what I can tell. The damper looks okay- it's cast iron- but there's so much debris around it I can't tell what's erosion and what's just junk. The pin that holds my clean out door is snapped, but the door itself is solid and it's case is still very solidly mounted in the base. There's some mortar missing at the rear outside edges of the fireplace, and between one or two bricks in the basement in one small section.
Someone I spoke to mentioned a shelf outside the fireplace?
And how do I determine what the outside structure of the chimney needs? I know it needs a cap, but the company that I am purchasing my wood burning insert from is going to provide me with one when they put the pipe/liner in for the exhaust.
I guess I'm just looking for guidelines about how to determine what a chimney/fireplace needs in order to be safe to have a wood burning insert installed so that I can judge for myself who and what is best for my home, because as you said, no one can tell me who to believe. But in order for me to judge, I need information. And at present, I am flying blind.
 
#23 ·
You get on a ladder and check out the structure from top to bottom. You look at the bricks and mortar. Is the mortar soft? Are the bricks loose? Bring a screwdriver up with you and probe the mortar. Does it crumble?
Does the whole chimney move?
You would do this BEFORE you buy and install a fireplace insert and liner.
Putting this in an unsound struture is inappropriate.
Post pictures of this chimney. Especially above the roof line, but below and to the side as well.
It sounds like these guys were blind or stupid or both.
Ron
 
#24 ·
and the next chimney ... spalling bricks

same problem, basically, some mortar has fallen out between lower bricks, and bricks along the roofline (and a couple above) are "spalling" - the faces are falling off.

3 contractors, 3 solutions, confused like everyone else:
1. tear it down and rebuild with concrete block
2. repair (?) lower bricks and repoint chimney
3. bolt (?) cement board all around the chimney to hold it in place (about half the price of 1 and 2 - but?)

All say metal liner should be added.

Chimney currently has a clay liner and a woodstove insert. No one recommends taking the chimney down and replacing with metalbestos chimney because a complicated "adaptor" is needed. ?

I'm sorry, no pic of chimney posted, but I'd love to get the opinion of you knowledgeable people about the 3 options above - and any others.

Thank you.
 
#25 ·
Chimney Rebuild

My 1927 house has a 2-flue unlined chimney. I've been told the chimney needs to be re-built up from roofline. This is to allow insertion of an aluminum liner in the gas flue (for the furnace) and a stainless steel liner for the woodburning insert we're putting in.

I've been quoted $7,800 + tax to have the following work done:
1) disassemble chimney to roof line
2) rebuild as per original construction
3) supply and install new chimney cap flashings
4) supply and install flex liner to gas flue to include connections in mechanical room and termination work at top of chimney
5) insulate approx. 2-3' in gas flue
6) supply and install extended concrete drip edge
7) supply and install 2 new contrete hooded pots and mortar wash
8) supply and install vertical wildlife and rain deterrents to side openings of new hooded pot installations
9) supply and apply 761 brick and masonry sealer to exterior of chimney from flashings to crown
10) remove debris to dedicated dump site

I've attached photos of the chimney and fireplace. Does this amount sound reasonable for the work to be performed?
 

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#27 ·
Yes, I've read about this method of lining a flue, but I am not aware of its use in Canada. Also, this method requires that the entire chimney be opened every two metres (and at any bend) to centralise the form. This may mean mess and disruption within the building and subsequent re-plastering and redecoration. So I think it might end up costing more than rebuilding the chimney from the roof up.