Reducing Firebox Opening for Gas Insert

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culleej

New Member
Dec 15, 2020
5
Milwaukee, WI
Hello,

I've done a lot research on this site on the best approach for this, and just want to make sure I'm heading down the right path. We are getting a Mendota FV44i installed in our existing gas fireplace, and I need to shrink the opening of the firebox. In the attached picture, the cardboard represents the mendota insert size.

To do this, I need to reduce the height by about 8" and each side by about 2". I believe the best approach is to buy angle steel, bolt to the brick on each sides and to the existing lintel and brick on the top row. Then, I will cover the existing brick and new steel with thin brick. The other option is use fire brick instead to close the opening, and still cover everything with thin brick for cosmetic appeal.

Thoughts? Any advice is much appreciated.

[Hearth.com] Reducing Firebox Opening for Gas Insert
 
The CORRECT way is to buy a surround that covers the opening.
You do NOT need to do anything else, unless Mendota doesn't
offer such an item.
 
Thank you for the suggestion, but I didn't want to have an 8" plain black surround. I much prefer brick work so trying to figure out how I make the framing option work.
 
Understood.
You can also cover the existing bricks with dura rock or hardee backer,
using Tapcons. That will give you a continuous surface for your faux brick.
Another way to reduce the top of the opening is by setting the insert on a riser,
It could be a steel box or a solid piece of bluestone, concrete, or even stacked bricks...
That way the surround doesn't need to be as large...
 
Hello,

I've done a lot research on this site on the best approach for this, and just want to make sure I'm heading down the right path. We are getting a Mendota FV44i installed in our existing gas fireplace, and I need to shrink the opening of the firebox. In the attached picture, the cardboard represents the mendota insert size.

To do this, I need to reduce the height by about 8" and each side by about 2". I believe the best approach is to buy angle steel, bolt to the brick on each sides and to the existing lintel and brick on the top row. Then, I will cover the existing brick and new steel with thin brick. The other option is use fire brick instead to close the opening, and still cover everything with thin brick for cosmetic appeal.

Thoughts? Any advice is much appreciated.

View attachment 269422
If it was mine, I would cover the whole area in between the mantle, with another product. Could be brick, stone, tile....