see inside: The near catastrophic results of an incorrect zero clearance install

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burgandy25

Member
Dec 2, 2017
6
MI
Reddit thread of a nearly catastrophic builders grade fireplace install:


It appears the studs in contact with the fireplace DID once catch fire they appear to have that charcoal appearance to them.

Crazy this house didn't catch on fire.
 
Oh look, its one of those self clearancing installs.

I can only imagine how sick that homeowner is feeling right now after looking at that. I'm so thankful they caught it.
 
Sadly it is very common to find improper clearances from prefab fireplaces. And very common to find charred wood in walls in all kinds of setups.
 
Sadly it is very common to find improper clearances from prefab fireplaces. And very common to find charred wood in walls in all kinds of setups.
I don't do cleanings or install, just a homeowner but you can't be serious? This is actually common? This is horrifying to think about especially thinking of the potential for families to be lost.

Do you see this with new home builders doing a poor install as well? Or usually a homeowner special?
 
I don't do cleanings or install, just a homeowner but you can't be serious? This is actually common? This is horrifying to think about especially thinking of the potential for families to be lost.

Do you see this with new home builders doing a poor install as well? Or usually a homeowner special?
Yes I see it with new home builders as well. I actually had a contractor argue with me that the chimney didn't need the 2" clearance clearly called for by stickers on the chimney because it's called zero clearance. This was on a pretty high end 1 year old house that passed all inspections. Many contractors just don't care or don't bother to actually read the directions.
 
Might have been poor burning practice, along with clearance issues too...who knows.
 
Certainly an interesting photo. Still seems to be something weird going on there. Sure, they didn't use the proper standoffs on top of the unit and it looks like there is blow-in insulation which rained down inside the chimney chase. But the most curious part to me is the charring on the sheetrock and 2x4 at the side of the firebox.

Looking back at the instructions for my fireplace, they call for only 7/16" clearance to 2x4 on the side of the unit. (I don't expect this is the exact same unit, but that clearance seems fairly typical.) Drywall can come a bit closer and touch the actual standoff. So I could see how you could jam a 2x4 closer, but it's hard to believe that at 7/16 inch clearance the unit would be perfectly fine for the lifetime of the house and at 5/16" it would char and burst into flames in a few years?!?! Similar on the top - yes, they have the 2x4's closer than the standoff. But the sheetrock can typically come down and touch the top of the unit. (ie it's essentially 'foolproof' in that you can but it right up to the standoff. But this sheetrock seems to be charred too.

I'm wondering if they are not burning gas with the damper closed, or that blown in insulation has closed off some of the air venting. Either way, it seems like a lot of heat building up there.

Will attach some images here and the key image - in case it gets pulled down.

clearances.jpg self clearancing.jpg
 
Certainly an interesting photo. Still seems to be something weird going on there. Sure, they didn't use the proper standoffs on top of the unit and it looks like there is blow-in insulation which rained down inside the chimney chase. But the most curious part to me is the charring on the sheetrock and 2x4 at the side of the firebox.

Looking back at the instructions for my fireplace, they call for only 7/16" clearance to 2x4 on the side of the unit. (I don't expect this is the exact same unit, but that clearance seems fairly typical.) Drywall can come a bit closer and touch the actual standoff. So I could see how you could jam a 2x4 closer, but it's hard to believe that at 7/16 inch clearance the unit would be perfectly fine for the lifetime of the house and at 5/16" it would char and burst into flames in a few years?!?! Similar on the top - yes, they have the 2x4's closer than the standoff. But the sheetrock can typically come down and touch the top of the unit. (ie it's essentially 'foolproof' in that you can but it right up to the standoff. But this sheetrock seems to be charred too.

I'm wondering if they are not burning gas with the damper closed, or that blown in insulation has closed off some of the air venting. Either way, it seems like a lot of heat building up there.

Will attach some images here and the key image - in case it gets pulled down.

View attachment 295334 View attachment 295335
It looks to me like those studs were most likely in contact with the fireplace and the insulation made matters worse which is why firestops and insulation shields are so important
 
It's not just prefabs that have an issue with careless contractor installation. Some masons and contractors don't think about the consequences of poor workmanship and code ignorance either. I've seen this in old houses and new.
 
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It's not just prefabs that have an issue with careless contractor installation. Some masons and contractors don't think about the consequences of poor workmanship and code ignorance either. I've seen this in old houses and new.
Absolutely very few masonry chimneys are built properly
 
Reddit thread of a nearly catastrophic builders grade fireplace install:


It appears the studs in contact with the fireplace DID once catch fire they appear to have that charcoal appearance to them.

Crazy this house didn't catch on fire.

I see nothing.
 
I'm wondering if they are not burning gas with the damper closed, or that blown in insulation has closed off some of the air venting. Either way, it seems like a lot of heat building up there.

Will attach some images here and the key image - in case it gets pulled down.

View attachment 295334 View attachment 295335
is this the OP's pic?

Looks like a corner unit where the carpenter perhaps made the header too low and the installer cut an opening just big enough to fit???

The studs are right on top of the unit on the stoves working side....what do you expect?

Why post the pic without some back story?
 
Then you
I thought all the beer cans acted as fire stops?
Then you've never put an (aluminum) can in a campfire. They just melt.
 
I don't do cleanings or install, just a homeowner but you can't be serious? This is actually common? This is horrifying to think about especially thinking of the potential for families to be lost.

Do you see this with new home builders doing a poor install as well? Or usually a homeowner special?
I was helping a friend with some projects in the house she bought from some flippers. Thank every deity she decided to get rid of the wood burning insert instead of using it - after we pulled it out, we discovered that they mismeasured the framing for a bumpout around the old hearth, so when they went to tile it it was off by 1/4" on one side and 1/2" on the other side (no, it wasn't even square, these jokers were super sloppy).

So what did they use to shim out the backer board for the tile with? Cardboard and plywood. Literally touching the insert on one side, with a nice floor to ceiling air gap on the other to make sure there was plenty of oxygen next to the tinder. Short of filling the wall with kerosene soaked rags, I'm not sure they could have made a better fire trap.
 
is this the OP's pic?

Looks like a corner unit where the carpenter perhaps made the header too low and the installer cut an opening just big enough to fit???

The studs are right on top of the unit on the stoves working side....what do you expect?

Why post the pic without some back story?
This was a reddit post by a homeowner who isn't the original owner/builder. He thought something wasn't right and cut an access hole and snapped the pic in the link, then posted it to Reddit asking if it's normal.
 
Sorry but I see no link in post #1 on my end, My comments were referring to pics in post#7. scary stuff.
I get what you guys are always warning about.
 
Sorry but I see no link in post #1 on my end, My comments were referring to pics in post#7. scary stuff.
I get what you guys are always warning about.
Those are pics from the original link