How big of a fireplace can I fit in a 33" rough opening?

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dri3s

New Member
Apr 15, 2020
2
Houston
Hi all.

We are in the midst of building our house (Houston, TX) and we are finding ourselves in quite a pickle.

The designer did not leave enough room for the precast Rumford Firerock fireplace that we selected. That fireplace was already going to be on the small side (30" firebox width). We need 38" to fit the precast fireplace into this space; instead, we have 33". Having a proper wood burning fireplace is high up on our list and we are going to get a mason to build one for us.

My question for you fine folks: given that we have a 33" rough opening, how big of a firebox can we have (assuming we use proper lining, firebrick, etc)? I am trying to interpret building code, but it is confusing as heck. Thanks in advance for your advice. We could sure use it.
 
Hi all.

We are in the midst of building our house (Houston, TX) and we are finding ourselves in quite a pickle.

The designer did not leave enough room for the precast Rumford Firerock fireplace that we selected. That fireplace was already going to be on the small side (30" firebox width). We need 38" to fit the precast fireplace into this space; instead, we have 33". Having a proper wood burning fireplace is high up on our list and we are going to get a mason to build one for us.

My question for you fine folks: given that we have a 33" rough opening, how big of a firebox can we have (assuming we use proper lining, firebrick, etc)? I am trying to interpret building code, but it is confusing as heck. Thanks in advance for your advice. We could sure use it.
Well first you will need a proper foundation hearth and hearth extension slab. Then you will need 8" minimum of solid masonry including the firebrick inner wall. So that would leave you with 17".
 
Why not just have a zero clearance high efficiency fire place installed? Would be a lot cheaper, and you would still have the nice fire view. That or a nice stand alone wood stove.
 
Why not just have a zero clearance high efficiency fire place installed? Would be a lot cheaper, and you would still have the nice fire view. That or a nice stand alone wood stove.
I don't know of any that will fit in 33" either
 
Welcome!

If you post all your dimensions, desire (area to be heated), and a few pictures, folks on here (not me :) )are remarkably adept at proposing a few options for you to consider.
 
Sight unseen it seems like a narrow gas fireplace may be the best solution unless the rough-in can be torn out and expanded to at least 36". Send the designer the bill for the change order.
 
Welcome!

If you post all your dimensions, desire (area to be heated), and a few pictures, folks on here (not me :) )are remarkably adept at proposing a few options for you to consider.

Thank you all for your replies. I have attached a picture of what we are working with. The big concern is the width between the studs - 33". I *think* the studs marked in green are not structural, but the ones in red are.

A mason I talked to said code is OK with 4 inches of firebrick lining the firebox. Do you all think he is right about that? The way I read it, code says 8 inches if you use 2 inches of firebrick...

The area to be heated is a 20 x 16 living room with a 10 foot ceiling. This is Houston, so we won't be relying on this year round (to say the least ;)).
 

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That looks more like a closet than a fireplace enclosure. With the green inner framing removed there is enough room to install a good quality Zero Clearance fireplace that will do a much better job of heating while providing a nice fireview. The face can still be done in masonry for a traditional look.

Otherwise, it may take some surgery to make this work for a fireplace, like moving the left side supports over 6" and the doorway to the left too.
 
Thank you all for your replies. I have attached a picture of what we are working with. The big concern is the width between the studs - 33". I *think* the studs marked in green are not structural, but the ones in red are.

A mason I talked to said code is OK with 4 inches of firebrick lining the firebox. Do you all think he is right about that? The way I read it, code says 8 inches if you use 2 inches of firebrick...

The area to be heated is a 20 x 16 living room with a 10 foot ceiling. This is Houston, so we won't be relying on this year round (to say the least ;)).
No 4" is absolutely not enough thickness. What is the house built on? If it is on slab is the slab thick enough to support the weight of a fireplace? If not on slab you will need to remove and restructure the floor then pour a footer and build a masonry supporting structure for the fireplace. Then pour the hearth and extension slab before even starting to build the firebox.

Honestly if you mason is claiming a fireplace can be built with just a single layer of firebrick it's time to find a new mason if you go this route