Flush hearth extension for wood stove

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If you are really anal about the gaps you could take a small piece of Durock and construction glue it into the 3/4 space as a filler. It wont be structural but easier than trying to block the underneath and then fill with mortar or something else.
 
Thanks for the suggestions. Did some research on applying cement board to concrete and it doesn’t sound like its recommended, has anyone here done this with good results. I guess another option is to put cement board over the subfloor and then add cement to the pad to bring it up to the same height and then tile over two different substrates, which also doesn’t sound like a good idea.


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Did some research on applying cement board to concrete and it doesn’t sound like its recommended
Source? I'm not a mason, but that doesn't make sense.

The tile needs a smooth, level and continuous surface to bond to. Cement board is ok to put over cement. You could build up the low area with cement board and then a continuous layer of micore topped with 1/2" of cement board or you could build up the low area with cement, then top with micore, cement board and tile.

https://www.ehow.com/how_6688739_using-floors-ceramic-tile-installation.html
 
Thanks for sharing this article. I was confusing your install with another in thinking there would be a micore layer. I see the pov of the author of the Spruce article. The concern is bonding and anchoring to the underlying concrete. If the concrete has any form of sealer or paint on it, the bond will be broken. This seems to be less of an issue on raw concrete, but there are differing opinions. Here is a back and forth discussion on the topic.
https://www.finehomebuilding.com/forum/durock-on-concrete-floor-2
 
I thought of that, but the manual for my stove states ember protection only unless installed in an alcove.
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It’s not being tucked into the fireplace. It’s going to sit outside the fireplace


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Ok then not an alcove. Technically to meet code because it is a permanent hearth extension for a fireplace it should meet that requirement which means a self supporting slab etc. But what you are planning should be perfectly safe
 
And tucking it into a fireplace makes it an alcove.
First time I have heard this, where is this info coming from? An in-the-fireplace install presents a different scenario than an alcove. Clearances to the ceiling, for example, are irrelevant and waved usually. Clearances to the mantle and side walls are key. If the hearth is properly done, then the r value is typically moot as is it specced to have a hot fire sitting on it continuously. That's why no wood is allowed under it, right?
 
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First time I have heard this, where is this info coming from? An in-the-fireplace install presents a different scenario than an alcove. Clearances to the ceiling, for example, are irrelevant and waved usually. Clearances to the mantle and side walls are key. If the hearth is properly done, then the r value is typically moot as is it specced to have a hot fire sitting on it continuously. That's why no wood is allowed under it, right?
Yes I agree it is different because the alcove is no combustible so those clearances don't apply. But clearly by trapping the heat in the enclosed space of an alcove it increases floor temps which means r value is required. Putting the stove in a fireplace would do the same thing.

But in this case the stove will be in front so it isn't an issue.
 
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That could be the theory, but it's not always clear. Some stoves have ember protection only hearth requirements for alcove installations, even with a lower than 84" ceiling requirement. It's not consistent.

Conversely, putting the stove in the fireplace automatically ensures adequate hearth protection as long as it is a properly built masonry fireplace. Of course, properly built is not always the case for the hearth extension in front of the fireplace as you have pointed out.
 
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That looks very nice. I’m impressed.
 
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Today, the install was finished, 27’ insulated SS liner with a block off plate and the stove put into position.
f28f7cc048a96cdb2a35cb434cc621a2.jpg3fc8967275736f30a8c968f1d8eacf78.jpg

Off the back of the stove is stainless pipe into a Tee. Anyone have any ideas for a non magnetic flue pipe thermometer?


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Today, the install was finished, 27’ insulated SS liner with a block off plate and the stove put into position.View attachment 246262View attachment 246263

Off the back of the stove is stainless pipe into a Tee. Anyone have any ideas for a non magnetic flue pipe thermometer?


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Pretty much all of the magnetic thermometers have a hole in the center you can run a screw through. But in your case I would recommend an auber remote thermometer because one on the pipe will be hard to see and will have to be very close to the stove giving you high readings
 
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Pretty much all of the magnetic thermometers have a hole in the center you can run a screw through. But in your case I would recommend an auber remote thermometer because one on the pipe will be hard to see and will have to be very close to the stove giving you high readings

I looked at the Auber, seems like the best option for me. Really like the option to have remote monitoring


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