re-face fireplace need some help

[6fthook]

I posted something similar in the DIY and General forum, was told I would get more advise here, so here it is.


We recently bought our first house and currently doing a lot of renovating before we move in, one of the projects being the fireplace. We are planning on re-facing the fireplace with veneer stone, probably cultured stone, and possibly in the future buying a wood burning insert (quadra-fire 2700 or 3100). We are also going to be hanging a TV on the chimney above the mantel. When we bought the house, it had white painted pine boards on top of the pictured 2x4 frame nailed to the brick, VERY ugly. I ripped that out and here is what it currently looks like:

The wood/tiled hearth, tile surround, and gold trim will be getting ripped out soon.

And here is what we are hoping to end up with after we are done:

So here is where we need your help, what is the best approach to turn our fireplace from picture #1 to picture #2?


I was thinking two approaches:

#1: Build a wood frame, similar to what is already there, screw metal lathe over the 2x4, then mortar and veneer stone over that. For the hearth I was thinking once again build a wooden rectangle box, metal lathe, mortar and veneer stone, then bluestone slab on top.
OR
#2: Lay another layer of brick on top of the existing layer to make it even with the extra layer around the fireplace opening, then mortar/veneer stone. For the hearth, 3 or so layers of brick stacked/mortared, then bluestone on top of that.


But I have concerns for both. #1, is a wooden frame against building code? I have heard both yes and no. For #2, I'm concerned about the weight of so much more brick.


Thanks for any advice you can give us! Much appreciated

 

[6fthook]

Here are some extra pictures of the fireplace/chimney:

 

[6fthook]

I realized that my first post may be a bit confusing to understand. My main question is:

The brick is currently flush with the drywall, we want it to extend into the room by at least a few inches. Before refacing with veneer stone, how can I add thickness to the brick without adding too much weight to the floors? Or is weight not an issue, and I can just add another layer of brick? Would a wood frame work, or is this against code?

Thanks!

 

[begreen]

Not my field, but I posted this thread earlier with some links on the topic:

https://www.hearth.com/talk/threads/74514/

 

[webby3650]

The first thing you will need to do is to remove all the wood framing from the fireplace face. If you choose to build it out, it should be done using non-combustible material. This could be done by laying steel studs flat and then use cement board over the studs to get the thickness you want.

 

[webby3650]

I also noticed that the firebox is made from red brick and mortar instead of firebrick, not a real problem, it just won't be as durable. It also appears that you are getting water on the back wall of the firebox, this often means you are missing a cap, or the crown of the chimney has cracks allowing water through. You might want to get up there and check it out.

 

[6fthook]

Thanks guys!

I was doing some research on steel studs, and people were saying that the steel studs cannot bear that much weight, and that even kitchen cabinets sometimes fail on them. Would it be able to hold up about a thousand pounds or so of weight as long as I fasten it correctly to the brick? I'm not doubting your knowledge or anything, I just want to make sure I'm understanding it right so that I can do it right.


Also, for the red brick you were saying, do you mean inside the firebox or the brick that is surrounding the firebox? If the latter do you think I should replace it since I will be doing so much work to the fireplace anyways? Or is it not a huge deal?

For my own knowledge, how can you tell that there's water coming in? The white spots on the back? I will get up there in the next few days to see if there's a crack or if the cap is missing or broken.

Thanks again!

 

[webby3650]

I wouldn't bother with replacing the brick inside of the firebox, installing an insert would be the way to go. The white spots on the fireback is what makes me suspect that you have some water coming in. If you lay steel studs flat against the block and securely fasten them, I don't see how they could fail, stone veneer doesn't weigh that much. Can you get the under the hearth? Find out if it is supported by the fireplace or if it is just sitting on the floor. If it is built properly, the hearth could support the weight of natural stone.

 

[begreen]

Use heavy-gauge steel studs and it should be fine. Just be sure they are solidly anchored. USG recommends 20ga or heavier.

 

[6fthook]

I had a mason contractor come out to get a price quote but it is more than what we can spend.

The contractor said that he would take out the gravel from underneath the hearth, clean it, put it back, and then pour concrete in to make a flat surface to build out a new hearth. I just want to make sure I understood him correctly. Here is a picture of underneath the chimney in the basement:

The gravel is underneath the hearth on top of the plywood in the basement:

Is there a name for this type of construction? And did I understand him correctly that I can just pour concrete into the gravel to form a flat surface to build a new hearth?

Thanks!

 

[elmoleaf]

Some comments/questions:
1. You are planning on removing the cantilevered concrete hearth extension (currently covered with tile) entirely, and rebuilding a hearth extension at floor level? You haven't included a picture of the firebox floor. Typically such a cantilevered construction is an integral part of the hearth inside the firebox...meaning more concrete under the firebox floor and/or rebar tying the cantilevered part into the chimney. Not necessarily an easy thing to demolish without knowledge and proper tools.

2. Your basement picture appears to show plywood formwork that's typically used when a concrete hearth extension is constructed at finished floor level. Typically the concrete is held recessed from the finished floor surface to allow topping tile to be flush with the wood floor surface. Are you certain there isn't already a concrete extension in there under the rubble? If there isn't, in theory you could remove the rubble and pour a slab...but you need to investigate tying it into the chimney structure with reinforcing steel. The hearth extension/chimney is supposed to be self supporting...you can't use the header beam or plywood to support it...the plywood is supposed to be removed after construction.

3. Combustible framing/wood trim needs to be held minimum distances away from firebox, and the hearth extension needs to be certain minimum dimensions. Consult your state building code or local building inspector.

4. You can likely adhere new facing brick or stone to the rough masonry that's behind the wood framing (get rid of it) in the photos. Depending on the thickness/weight of new facing material, you might need to also add metal masonry anchors.

5. If you drop the hearth height, you'll also need to figure out how to neatly trim out the face below the firebox floor, and the lip of same.

6. The easiest course of action may be to keep the existing hearth extension and reface it, rather than dropping it to floor level. However, if you plan on converting to a freestanding stove in the future, it might make more sense to get rid of the cantilevered extension (and then take steps to replace it with code compliant fireplace hearth extension if fireplace remains for time being, or replaced with proper stove pad if fireplace will be removed/permanently sealed up).

7. Don't assume that what exists there now is necessarily safe or code-compliant. You may find other problems to fix as you work on this project.

 

[6fthook]

Some comments/questions:
1. You are planning on removing the cantilevered concrete hearth extension (currently covered with tile) entirely, and rebuilding a hearth extension at floor level? You haven't included a picture of the firebox floor. Typically such a cantilevered construction is an integral part of the hearth inside the firebox...meaning more concrete under the firebox floor and/or rebar tying the cantilevered part into the chimney. Not necessarily an easy thing to demolish without knowledge and proper tools.

2. Your basement picture appears to show plywood formwork that's typically used when a concrete hearth extension is constructed at finished floor level. Typically the concrete is held recessed from the finished floor surface to allow topping tile to be flush with the wood floor surface. Are you certain there isn't already a concrete extension in there under the rubble? If there isn't, in theory you could remove the rubble and pour a slab...but you need to investigate tying it into the chimney structure with reinforcing steel. The hearth extension/chimney is supposed to be self supporting...you can't use the header beam or plywood to support it...the plywood is supposed to be removed after construction.

3. Combustible framing/wood trim needs to be held minimum distances away from firebox, and the hearth extension needs to be certain minimum dimensions. Consult your state building code or local building inspector.

4. You can likely adhere new facing brick or stone to the rough masonry that's behind the wood framing (get rid of it) in the photos. Depending on the thickness/weight of new facing material, you might need to also add metal masonry anchors.

5. If you drop the hearth height, you'll also need to figure out how to neatly trim out the face below the firebox floor, and the lip of same.

6. The easiest course of action may be to keep the existing hearth extension and reface it, rather than dropping it to floor level. However, if you plan on converting to a freestanding stove in the future, it might make more sense to get rid of the cantilevered extension (and then take steps to replace it with code compliant fireplace hearth extension if fireplace remains for time being, or replaced with proper stove pad if fireplace will be removed/permanently sealed up).

7. Don't assume that what exists there now is necessarily safe or code-compliant. You may find other problems to fix as you work on this project.

1. The hearth extension was held up by 2x8 or 2x6 board framing the perimeter of the hearth, with the ends nailed onto the vertical 2x4s. The firebox brick build-out is laying on top of the hearth, and also mortared onto the chimney face (this mortar is already de-tached to the chimney).

2. I will investigate when I have time hopefully soon to find out if there is already concrete under there. If there is no concrete and I need to pour myself including tying it to the chimney structure with the steel, is it something that I can do with no experience?

3. I have all the minimum distances needed via the NFPA 211 codes with minimum hearth dimensions depending on firebox dimensions, and also minimum combustible material distance from the face and firebox. Just trying to figure out the best way to frame it up to be compliant.

4. Adding another layer of brick with mortar to the existing brick then thin veneer stone over that would be my prefered method of re-facing. The reason being I want to add a tiny bit of thickness into the room. Only thing I am uncertain about is if all the added weight will be ok for the floor. Do you think I can just add a few vertical beams in the basement to support the nearby floor joists if weight is an issue?

5. I plan on having a bluestone topped hearth at the same level as the firebox opening (spark strip under the seam) so it's a smooth transition.

6. The hearth extension including the brick layer around the firebox is already pretty much de-tached, just several nails holding it to the chimney now.

7. I definitely want to do this right and be as code-compliant as possible, hence all my questions. Am I ok for code-compliance as long as I follow NFPA 211?

Thanks a lot!

 

[begreen]

There is also the International Residential Code which most states adhere to.

 

[6fthook]

Thanks BeGreen, I will look into that code

 

[6fthook]

Finally got around to work on the fireplace again today. The wood 2x4s, hearth, and brick firebox surround is now gone. I shoveled most of the gravel/stonedust out, and here is what I found:

The cinderblocks or CMUs they used for the chimney base is not reinforced with rebar and is not filled in with concrete. Should this be a concern? Or is it not a big deal and I should just leave it and move on?

They put bricks or pieces of brick to cover the cinder block holes.