ID'ing type of fireplace, and potential insulation issues

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Ben311

New Member
Oct 3, 2020
15
Ontario, Canada
Hi,

I moved into a house built in 1989 that has a wood burning fireplace. I have never used it. Last year, I had the chimney swept. The sweeper said that since there are signs of moisture in the fireplace, he cannot be sure that the water leak had not rusted through the chimney liner, and thereafter dampened the insulation, essentially pushing it down and leaving areas with no insulation.

Given that, I did not use the chimney at all, and hadn't looked at it further. A few weeks ago, however, I went on the roof and tested to find the area that is leaking water, as it had recently began to visibly drip water in the fireplace when it rained I need to stop further water damage. The leak is now repaired (as per another thread).

Now I am reading more about fireplaces and associated insulation. From what I can tell, most insert fireplaces aren't actually insulated? My naive impression was that the entire chimney is typically insulated, but this is not the case, correct? So what could the sweeper have been talking about regarding insulation being damaged? I don't think my fireplace is a zero-clearance (which requires insulation as it is in contact with wood, etc).

So my questions are:

1) is this an insert fireplace or zero-clearance?
2) do I have to take the tiles off surrounding it to remove the insert piece so I can see up the flue and inspect insulation?
3) I have also attached a pic from the top looking down the liner. I don't see any rust or water damage--so the liner must be intact?
4) what areas exactly need to be insulated? I have a purchased a bunch of Rockwool, but does it need to go all up the chimney cavity from bottom to top, along all four sides (and underneath the fireplace)?

Thanks!

[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues
 
This is a zero-clearance fireplace. It is sometimes called an insert fireplace, but as you can see that terminology is confusing. I am not sure what type of chimney pipe is on this ZC. Some are air-cooled, triple-wall and have no insulation.
 
Did he take a picture of the chimney top, also called a chase cover? That’s the most likely cause of your water infiltration.
 
The insulation the sweep was referring to is In between the walls of your chimney pipe. It can’t be replaced. It’s highly unlikely that it’s compromised..
I would remove a panel of siding on the back of the chase to inspect. You will very likely see water damage coming from a leak in the chase cover, roof flashing, or those angled areas where the chase narrows. Those angles are begging for a leak!
While you’re in there, you can make certain there is a proper draft stop above the unit and the walls of the chase below that are insulated. It’s often overlooked by the builder.
 
And here is the pic of the liner


No, he did not, but I did take one a few weeks ago, attached. Thanks
Uhhhh yeah of course it is leaking. That top is rediculous. I can't believe anyone thought that could work.
 
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Holy cow! You could start by replacing the chase cover with a stainless cover that’s made properly. Inspect the chase from above for water damage. Go down the line from there. Looks like security chimney pipe.
 
The insulation the sweep was referring to is In between the walls of your chimney pipe. It can’t be replaced. It’s highly unlikely that it’s compromised..
I would remove a panel of siding on the back of the chase to inspect. You will very likely see water damage coming from a leak in the chase cover, roof flashing, or those angled areas where the chase narrows. Those angles are begging for a leak!
While you’re in there, you can make certain there is a proper draft stop above the unit and the walls of the chase below that are insulated. It’s often overlooked by the builder.
Uhhhh yeah of course it is leaking. That top is rediculous. I can't believe anyone thought that could work.
Holy cow! You could start by replacing the chase cover with a stainless cover that’s made properly. Inspect the chase from above for water damage. Go down the line from there. Looks like security chimney pipe.
That is some kind of a joke. Put a proper chase cover on there and be done with the issues. Rockford sells custom covers.

Thanks everyone for the replies. I did not know the chimney cap was that terrible!

First off, I have a chimney inspector coming in 2 weeks to take a look at this. I am a bit dismayed that my last WETT inspection (when I bought the house) and subsequent chimney sweep a year later did not even mention the poor shape of the chimney cap.

Nevertheless, the main source of the leak was around the flashing where the chimney meets the roof. It was not step flashing. I have temporarily fixed it with mastic (it has rained several times since, and there is no more leaking). I am going to go up and re-do the step flashing properly after my inspection.

In the meantime, I have been investigating the extent of the water damage. As per my original post, my last chimney sweeper (who I am not impressed with, given the lack of mention of the chimney cap, and my suspicion that he was just trying to upsell my to get a new liner) raised a flag that the water damage might have "washed out" some of the insulation, creating a fire hazard. This was not based on actually inspecting the chimney, but just due to the fact that there was an apparent leak at the time.

I have removed the vents above the fireplace in the interior of my house to visually inspect the water damage, and if there is any damage to the liner itself. I have attached many pictures of this process. I have some points/questions about these in preparation for the inspector:


Picture A - this is just view of the fireplace to give you some perspective of where the other pictures are taken, and where the drywall/insulation within the chase. Ignore that the insulations stuffed into the vents, that is temporary until we have our inspection.

Picture B) This is looking down to the fireplace itself, on the left side, where it turns out most/all of the water damage has occurred. Is the black stuff on the wall directly beside the top of the fireplace soot, or mold? I would have excepted mold, but it seems like a strange place for it to occur (just above the fireplace, on both sides as in Pic D), instead of on the entire length wall.

Picture C - This is the worst spot by far, as it is looking up the chase on the left hand side at where the leak had been coming from. There is obvious damage to the drywall and insulation here. I will need to replace this, and I am thinking that I will need to cut out the drywall on the wall above the fireplace to access it, replace the drywall piece within, as well as the insulation above the drywall, the patch the hole in the wall.

In its present condition, does it present a fire/safety risk? Or is the drywall/insulation only here to help prevent loss of heat from the house itself (to prevent high energy bills)? In other words, was this damaged drywall and insulation doing something to mitigate the risk of a chase fire? Or is that the sole purpose of the liner (which looks fine)?

Shouldn't the insulation by Rockwool instead of Fibreglass (more fire/heat resistant)?

Picture D - Similar to Pic B, but on the right hand side. Here you can get a better view of the space behind the fireplace. The drywall is clearly peeling. That can't be normal, right? Would placing some rockwool insulation between the back of the fireplace and the wall be a better option? The Rockwool would likely then be touching the fireplace.

Picture E - Looking up the right side. Some very minor water damage, so I don't think anything needs to be done here (phew).

Picture F - This is a shot of the metal liner with model number. I still can't see any water damage, at least that would cause a hole in the liner or otherwise (coupled with my picture of the interior of the liner in my first post). For those of you that see these often, does this look normal to you?

Thanks for taking a look at this, and sorry for the length update. I will of course by asking my inspector these questions, but given my 2 previous poor experiences, I was hoping for some insight from this forum first.

[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues
 
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That looks like black mold to me which is a health hazard. I would start at top with a proper chase cover, then work on remediation.
 
Ouch! What a mess. The 3rd photo looks questionable. Any chance that represents heat damage? Pro's?
 
It's hard to tell, but I am guessing it is a combo of water damage and heat damage showing in picture D.
 
That looks like black mold to me which is a health hazard. I would start at top with a proper chase cover, then work on remediation.
Ouch! What a mess. The 3rd photo looks questionable. Any chance that represents heat damage? Pro's?

Thanks for the insight. What is the best way to access this? From the exterior (remove siding, wood, drywall)? Can I get to it from the interior? I don't see any way to slide the firebox out. Would there be screws to unscrew and do so if I RIP out the tiles on the front?
 
I don’t see any “heat” damage. It’s water damage and it’s pretty severe. With remove the face of the fireplace, or the siding on the back, whichever is easier. As bad as it looks might need to remove everything and start over.
 
Picture D looks like the paper on the drywall broke loose due to the moisture issues and got too close to the fireplace jacket. But that is just an armchair observation. On-site inspection would better determine what is happening.
To fix it looks like the back of the chase is going to need to be opened and the water damage repaired after a proper chase cover is in place.
 
Here's an update with pictures, so you can feel my pain. I spent an hour or so on this today to get an idea of what I am working with regarding water damage. Here are the sequential pics as an update... I think they speak for themselves :(

[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues
 
Not sure if anyone gave an ID on the ZC fireplace but it looks like a BIS tradition
 
I stripped off some more siding today. Major damage on half of the chase. Lots of moldy drywall was removed. It is brutal. Im going to try to replace the framing. I will have to remove the insert... not sure how to do it, any thoughts? It is huge! It appears to be attached to the front frame with some hex bolts.
[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues[Hearth.com] ID'ing type of fireplace, and potential insulation issues
 
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I am guessing the bottom right of the tag says "Security Chimney International" ? BIS (Built In Stove) was owned by SCI up until I believe early to mid 90's maybe later they are now owned by International Hearth Products. I have seen a few threads here on them and parts available online.
 
Yeah they are decent early high efficiency fireplaces
 
I am guessing the bottom right of the tag says "Security Chimney International" ? BIS (Built In Stove) was owned by SCI up until I believe early to mid 90's maybe later they are now owned by International Hearth Products. I have seen a few threads here on them and parts available online.
Yeah they are decent early high efficiency fireplaces

Thanks for ID'ing this. Now I can find the manual online, which helps. However, the manual doesn't say anything about how the fireplace is secured, aside from some nailing flanges. I can't see any nails on mine, but it doesn't budge. I started another thread on this topic so it doesn't get lost in this thread, as I need to get it out asap: https://www.hearth.com/talk/threads/how-do-i-remove-a-bis-traditional-zero-clearance.183085/
 
Another update for fun:

I went on the roof and removed the chimney cap. Prior to removal, there was a big puddle of water on top of the cover. Underneath, the wood was wet. So it looks like everyone was correct, and this was the source of a leak. I have ordered a new cover from Rockford-it might take a bit longer to ship to Canada.

At least it looks like there is no water damage looking down all the way to the firestop.

You will very likely see water damage coming from a leak in the chase cover, roof flashing, or those angled areas where the chase narrows. Those angles are begging for a leak!

The water damage is all located at the point of the angled areas where the chase narrows to the bottom of the chase. So, either a) the water coming in from the chase cover (because there is intrusion, I saw it) is falling right down the chase and not causing damage until it pools at the firestop area (the same point where the chase narrows), where it starts to cause damage, b) there is additional leakage at the flashing in the narrow area which is actually causing the extensive damage and therefore the chimney cover leak is insignificant, or c) a combination of both a and b.

I will have to put all of the flashing and siding back together after I reframe this, so hopefully redoing both the cover and flashing will stop all water intrusion.
 

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