Hearth extension fell into crawlspace with the help of sledgehammer

[Hearthbreaker]

My wife and I wanted to replace the tile on our hearth extension. It wouldn't budge so we needed to persuade it with a sledgehammer. Now we no longer have a hearth extension. Instead, we have a giant hole. We also released no fewer than three ghosts! I'm aware that we're going to need to sell the house at a loss now that it's haunted, but let's pretend it wasn't. How do we fix this?

It appears as if the tile "underlayment" was a cinder-block "ceiling" on top of a cinder-block three-sided box (with the four side supported by the four pillars that support the hearth itself).

What are those "ceiling" blocks called? Should I even bother trying to find replacements? Should I set a bunch of cinder blocks in the hole and file them with concrete or something?

I looked at one other thread (https://www.hearth.com/talk/threads/uh-oh-accidentally-destroyed-hearth-extension-base.10280/), but it sounded like their situation was a bit different.

Any advice will be much appreciated.

Thanks!

 

[Jags]

What is the distance of the gap, and what are your requirements for R rating?

 

[Fastdonzi]

Hence the Screen Name You could fill that with Cement, Then a top leveler and tile over it or what ever your finish is going to be,,

 

[billb3]

they make hollow blocks in many dimensions/sizes, that's likely an 'off the shelf' block you won't likely find at a big box store but anyplace that sells bricks/building materials should.

You could always cast your own.

 

[Oldman47]

A piece of masonry that spans a gap is called a lintel, but so what? If there is no combustible materials under your hearth location keep it that way. Use what you like to span the gap and apply your preferred final finish layer. In your place I would use some nice thin cinder block, like 4 inch, to span the opening then use a leveling compound to prepare it for final tiling or whatever you intend to use.

 

[bholler]

We usually just make a sheet metal pan and pour the hearth extension you can remove some of the existing block if you want it to be flush or pour it to what ever height you want really. Just make sure what ever you do that you tie it back into the fireplace structue we usually drill rebar into the pad under the firebox floor at different angles to lock everything together.

 

[HarvestMan]

This immediately came to mind (sorry, could not resist):

 

[Oldman47]

That tune reminds me of a poor computer game made for my Commodore in the early 80s. Yes I owned a computer back then. The tune kept repeating throughout the entire game.

 

[BrotherBart]

99% of the hearths in homes have that hole filled with crap and scrap brick pieces from when they were building the house and chimney. Look at it from the basement. There should be cantilevered cement with rebar in it under the fireplace.