Chimney crown cap repair- best practice and advice

[vbu]

Good morning gents,

We've owned this home for about two years, and had a quadra fire insert installed two seasons ago. They told us then that there were 2 flues uncovered.
Anyway, the time has come to repair the chimney cap. Obviously two plates will have to be made to cover up the unused flues. What is the common way to attach these plates to the liner?
I live in the south, so it's hard to find competent people to work on chimneys, that's why I'm asking for advice. What is the best way to fix this cap, how should it be done, and what should it look like after its done? Anything I need to look out for? I do not intend to do this myself (I don't do heights lol), but I want to make sure it's done right. Pictures attached for clarification.

Thanks guys

 

[bholler]

Good morning gents,

We've owned this home for about two years, and had a quadra fire insert installed two seasons ago. They told us then that there were 2 flues uncovered.
Anyway, the time has come to repair the chimney cap. Obviously two plates will have to be made to cover up the unused flues. What is the common way to attach these plates to the liner?
I live in the south, so it's hard to find competent people to work on chimneys, that's why I'm asking for advice. What is the best way to fix this cap, how should it be done, and what should it look like after its done? Anything I need to look out for? I do not intend to do this myself (I don't do heights lol), but I want to make sure it's done right. Pictures attached for clarification.

Thanks guys

View attachment 295750 View attachment 295751

The best thing for that chimney would be a poured crown and single multi flue cap. Just make sure the crown has a bond break under it and expansion joints around each liner

 

[vbu]

The best thing for that chimney would be a poured crown and single multi flue cap. Just make sure the crown has a bond break under it and expansion joints around each liner

Thank you for your quick reply. I did some research on the poured crown. The bond break is between the brick of the chimney and the cap, correct? What is the common material to use for this, and what is the correct way to do this?
What material should the expansion joints be made of? And is it necessary to have them around the flues that are unused?

Thanks again

 

[begreen]

Sakrete sells a fiber-reinforced concrete which should hold up better. Note that the top should be sloped away from the flues to shed rain easily. This video is helpful.

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[bholler]

Thank you for your quick reply. I did some research on the poured crown. The bond break is between the brick of the chimney and the cap, correct? What is the common material to use for this, and what is the correct way to do this?
What material should the expansion joints be made of? And is it necessary to have them around the flues that are unused?

Thanks again

We use just a sheet of plastic between the crown and the chimney. And wrap each liner with sill seal foam

 

[begreen]

What is your preferred concrete mix? Do you add rebar?

 

[bholler]

What is your preferred concrete mix? Do you add rebar?

No rebar. We mix 2 sand 2 stone and 1 Portland with fiber reinforcement added. And acrylic modifier

 

[vbu]

Ok guys so I reached out to the only fireplace store in this area (gotta love the south). I don’t think they’re familiar with pouring caps, as they suggested a solid metal cap instead of pouring one. Is something like that an option? Can you still use a multi flue cap when you use a metal cap?

 

[bholler]

Ok guys so I reached out to the only fireplace store in this area (gotta love the south). I don’t think they’re familiar with pouring caps, as they suggested a solid metal cap instead of pouring one. Is something like that an option? Can you still use a multi flue cap when you use a metal cap?

It is a decent option as long as it's stainless. And yes you can use a multi flue cap. I still prefer a poured crown for various reasons but a chase cover works

 

[vbu]

It is a decent option as long as it's stainless. And yes you can use a multi flue cap. I still prefer a poured crown for various reasons but a chase cover works

Thank you once again for your reply. I would prefer a poured crown too, but it is so hard to find anyone who will do it here. I've found some companies that do it about 100 miles from here, and they posted some pictures of their work. Based on their pictures they will not be touching my chimney, lol. Aesthetically I'd prefer a poured crown too but seems like a cover is a more fool proof way, ie. less ways to mess it up during install.

From pictures i've seen, it looks like they attach with some set screws on the side. Is that the only/normal way it is done?
Since I am using only one flue, I guess it would be an option to cut the other flue tiles flush with the crown, and just put a regular cap on, am I correct?
What is the correct way to attach the cap to the cover, and still have it water tight? Would self tappers be acceptable, or is there a better way?

Once again I'm sorry for all the questions, but knowledge here in the south is so much less than what you guys know, so thanks again for all the replies.

 

[bholler]

Thank you once again for your reply. I would prefer a poured crown too, but it is so hard to find anyone who will do it here. I've found some companies that do it about 100 miles from here, and they posted some pictures of their work. Based on their pictures they will not be touching my chimney, lol. Aesthetically I'd prefer a poured crown too but seems like a cover is a more fool proof way, ie. less ways to mess it up during install.

From pictures i've seen, it looks like they attach with some set screws on the side. Is that the only/normal way it is done?
Since I am using only one flue, I guess it would be an option to cut the other flue tiles flush with the crown, and just put a regular cap on, am I correct?
What is the correct way to attach the cap to the cover, and still have it water tight? Would self tappers be acceptable, or is there a better way?

Once again I'm sorry for all the questions, but knowledge here in the south is so much less than what you guys know, so thanks again for all the replies.

The few I have done I attach through the sides with stainless tapcons. And yes if you are sure you won't be using the other flues it's best to cut them down and cover. I would rivet or weld the cap on.

 

[vbu]

The few I have done I attach through the sides with stainless tapcons. And yes if you are sure you won't be using the other flues it's best to cut them down and cover. I would rivet or weld the cap on.

Thank you sir. Yes the other flues have concrete and rubble in them, I don't have a clue where they terminate, so no chance of them being used. I like the rivet/weld idea. Thanks again.