What is this hearth made of

[faultymechanics]

So I have a history on this site of trying to figure out what the heck is up with my hearth.

Ive recently started investigating as we may be ready to put a new insert in.

I know there is a concrete hearth and extension underneath as I can see it and the form from the basement(my past threads have some photos). However, looking now, it appears there is some kind of thick brick installed on the floor.

Appears to be gray on the top but brittle and a seemingly porous stone, whitish on the inside when broken.



Now in addition, as you'll see in my.other photos it appears as though the original fireplace was broken out and some kind of pre-made brick hearth insert was installed? Anyone seen this kind of thing before?

I shoved a screwdriver next to the stone to try and get an idea how thick both the hearth extension is and the brick under the insert.

This next photo is attempting to show the thickness of the hearth extension tile.

Lots of questions I'm hoping I can get help answering.

To summarize, is this some kind of fireplace rebuilt brick insert they put in after demoing part of the original fireplace?

What brick was used to line the floor of the fireplace/under the insert?

Is that brick on the hearth floor and the tile on the extension good enough to satisfy the R value ratings inserts require?

What other info can I get or provide to help figure this all out?

Thank you

 

[begreen]

Previous thread links

F

Post in thread 'Improving R value of hearth'

Sep 9, 2022

To make sure you have all the clearances and r values you should probably just pick an insert and build to to those specs. I have the Drolet 1800i. It sticks out a bit. To be honest I like the flush insert look. Just come up with a backup power solution. My plan is a computer batter backup. And then My generator if needed.

I actually have a couple spare UPS' that I keep charging in the basement. Are the fans loud on those flush models? I like the idea of silence whenever possible.

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