DIY liner question - Searched everywhere

[One_Odd_Twitchy]

Good evening,

I've searched all over and haven't found an answer for this particular question. At least, not that I understand.

I have a home built in the late 50s. It has a massive fireplace/chimney, the opening is 41 W x 23 D x 31.5 H, and I had my inspection done and there were a couple cracks inside. I've been talking about doing a stove/liner for passed couple years but with the new inspection and the winter coming I should go ahead and do it. That chimney goes up 11ft to the ceiling and its in the middle of the house (I have a low pitch, nearly flat roof, so 6-8 inches separate the ceiling from the rooftop), and the chimney goes out of the roof a little more than 3 feet, maybe closer to four. I've been looking for information on insulation requirements, because the tech who checked told me I'd be able to run the liner through and place/secure rockwool at the cap of the chimney, and for the fireplace side add some rockwool behind the plate where the old damper was and that would insulate it properly. Unfortunately, while I do some tradework for a living, this area is not my expertise and when I've been reading about rockwool suitability it hasn't seemed to help me understand any better.

Thank you for your time.

 

[Ctwoodtick]

I would use a stainless liner with insulation wrap. For blocking off the the damper area- search for block off plates in the search feature. No need to insulate the cap area up top.

 

[bholler]

Good evening,

I've searched all over and haven't found an answer for this particular question. At least, not that I understand.

I have a home built in the late 50s. It has a massive fireplace/chimney, the opening is 41 W x 23 D x 31.5 H, and I had my inspection done and there were a couple cracks inside. I've been talking about doing a stove/liner for passed couple years but with the new inspection and the winter coming I should go ahead and do it. That chimney goes up 11ft to the ceiling and its in the middle of the house (I have a low pitch, nearly flat roof, so 6-8 inches separate the ceiling from the rooftop), and the chimney goes out of the roof a little more than 3 feet, maybe closer to four. I've been looking for information on insulation requirements, because the tech who checked told me I'd be able to run the liner through and place/secure rockwool at the cap of the chimney, and for the fireplace side add some rockwool behind the plate where the old damper was and that would insulate it properly. Unfortunately, while I do some tradework for a living, this area is not my expertise and when I've been reading about rockwool suitability it hasn't seemed to help me understand any better.

Thank you for your time.

View attachment 317138

Insulation requirements are determined by the clearances from the outside of the masonry structure to combustibles

 

[One_Odd_Twitchy]

Thank you all for your help!