Firebox constructed on combustible material

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uhohfirebox

New Member
Jan 3, 2018
1
Eastern
Recently bought a home and had it swept for the first time before using our wood fireplace. Please see the quotes from the inspection and included photos of the wood framing:

"This chimney is interior by definition, contains 2 flues serving one fireplace and two natural gas, heat and hot
water appliances. Each flue was originally terra cotta lined but the heating appliance flue has been relined with stainless steel."

"The firebox (inner hearth) was constructed on combustible material. This material is charred and there is evidence of combustion in this location. This is a potential hazard. This condition did not develop from dumping hot ashes down the ash pit, it occurred due to heat transfer through the masonry materials, and it occurred over time. The home framing, heating appliance flue and the fireplace are all impacted by this condition."

"Damaged material was found in the smoke chamber area. This damage may allow the passage of heat, smoke and other combustion byproducts to areas of the chimney and home not meant to contain them. This damage occurred from age, use, and exposure. The smoke chamber also exceeds the height allowance for safe operation. This leads to a clearance to combustibles issues to the combustible walls above the fireplace in the chamber area."

What are my options here?
1.
Would this be covered by home insurance since there is evidence of combustion or is this more categorized as poor construction and may not be covered?
2. If I do have to absorb the cost, what is the most cost-effective way to fix this? The inspector basically said that I have to rebuild and quoted $11k, so I am hoping there is a cheaper option. I assume the flue can use a metal liner pretty easily but the firebox could be a problem.
3. I am okay converting to gas if it will save cost.
4. Should I just abandon ship on using it altogether?

Firebox constructed on combustible material Firebox constructed on combustible material
 
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Recently bought a home and had it swept for the first time before using our wood fireplace. Please see the quotes from the inspection and included photos of the wood framing:

"This chimney is interior by definition, contains 2 flues serving one fireplace and two natural gas, heat and hot
water appliances. Each flue was originally terra cotta lined but the heating appliance flue has been relined with stainless steel."

"The firebox (inner hearth) was constructed on combustible material. This material is charred and there is evidence of combustion in this location. This is a potential hazard. This condition did not develop from dumping hot ashes down the ash pit, it occurred due to heat transfer through the masonry materials, and it occurred over time. The home framing, heating appliance flue and the fireplace are all impacted by this condition."

"Damaged material was found in the smoke chamber area. This damage may allow the passage of heat, smoke and other combustion byproducts to areas of the chimney and home not meant to contain them. This damage occurred from age, use, and exposure. The smoke chamber also exceeds the height allowance for safe operation. This leads to a clearance to combustibles issues to the combustible walls above the fireplace in the chamber area."

What are my options here?
1.
Would this be covered by home insurance since there is evidence of combustion or is this more categorized as poor construction and may not be covered?
2. If I do have to absorb the cost, what is the most cost-effective way to fix this? The inspector basically said that I have to rebuild and quoted $11k, so I am hoping there is a cheaper option. I assume the flue can use a metal liner pretty easily but the firebox could be a problem.
3. I am okay converting to gas if it will save cost.
4. Should I just abandon ship on using it altogether?

View attachment 219569

View attachment 219570
I dont have any help, but I will give you a bump to the top

Sent from my GT-P5113 using Tapatalk
 
I can’t tell what I’m looking at in the pics.
 
The plywood underneath is not uncommon at all just open up the ash pit and cut it out
 
I came across this thread because I have a similar issue in my home. The ash pit is about 2' x 10' and about 3' tall with just a 6x9" opening in the cinderblock in the crawlspace. I hired a local chimney company to clean & inspect the system, and the technician gave it a clean bill of health. I smelled something earthy and looked down into the ash dump. Sure enough, there were ragged strips of plywood sticking across the hole! The pre-purchase inspection completely missed it.

I "fixed" the problem by raising and cementing a piece of concrete block into the ash dump and filling the chute with 12" of concrete. My plan was to pour another 12" to bring it all the way up, then replace the ash dump door with a firebrick. But at this point no ash is going to get through.

Opening the ash pit enough to get decent reach would entail cutting the entire end of open and crawling in. The ash pit is too darn big.

I didn't see any evidence of charring on the plywood. It's about 2 1/2 feet down from the firebox to the ash pit which is greater than the clearance to attic insulation from the flue. Is there really still a risk of combustion purely through heat conduction??

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I see there's a similar thread here.
 
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