Teach me about adding a fireplace

In reply to SVreX :

Peat!

In reply to dculberson :

Got it. Thanks!

Never heard it called turf before. 

So, does a turf fire (peat fire) have a unique smell?  I’ve never seen one. 

Peat fires smell wonderful.  A little acrid, but lovely.

So, SVrex... Can you expand on the flue differences?  Stainless double wall (at least the stuff I've seen) is relatively light.  Are you saying I can't use lighter weight flue material with a masonry fire box?

I'm weighing the pros and cons; do I want the additional work and cost of a masonry box?  But if a masonry box requires the additional weight of heavier flue material and the other associated things, I'll have to give up on that idea.  A metal fireplace is the easy button, but if I can make masonry work, I'd still like to hang on to that dream.

It just seems like (to this complete noob) that if I can install a metal firebox with 1" of clearance to combustibles, or a masonry box with 2" clearance and some floor support, and face either one with some stone, I might spend the extra on a masonry box... but it sounds like there is more to it.  Can you expand?

I reached out to the township office but they have limited hours.  They're pretty good about getting back to me; at least they were when I was buying the house.  I just want to be ready to answer the questions they'll be asking.  I realize I might gather all of this information and they'll require something for code that I can't provide, but I really have an itch that can only be scratched with fire.

In reply to Curtis :

To be honest, I have never seen that nor considered it.

Combining masonry firebox with metal flue components is a mixed metaphor.  The components are not necessarily designed to work together.

So, for example, a typical masonry firebox has a damper that is designed to mate with masonry flue tiles.  A typical metal fireplace firebox has a flange that is designed to mate to metal flue pipes.

If you mix them up, you are going to have to fabricate something (aka: rig up some E36 M3) to make the transition.  This is likely to be the failure point in the event of an incident.  I doubt you will find an inspector anywhere who would sign off on a mixed metaphor approach.

Additionally, you CAN'T put a masonry firebox on a wood floor structure.  At all.  Even if the floor was capable of holding the weight (it's not), wood expands and contracts, and masonry does not.  At some point you would have gaps developing between the two materials, which could be a fire hazard.

A masonry firebox does not sit on a wood floor.  The floor is cut out, and footings are installed at the ground level.  Masonry support is built all the way from the ground to support the firebox and transfer the load to the footings, not the wood floor structure.  The wood structure free-floats from the masonry fireplace support entirely.

Does that make sense?

Even a masonry system like Isokern (lego-like blocks made from lightweight volcanic ash) which weighs about 30% of standard masonry components is not suitable to install on a wood floor structure.

Plus, the weight of a masonry system does not stop with the firebox and flue tile.  It typically will have an entire masonry chimney surrounding the flue tiles, all the way from the ground the to chimney cap.

That's a lot of brick, stone, etc. to lay.

SVreX said:

In reply to Curtis :

To be honest, I have never seen that nor considered it.

Combining masonry firebox with metal flue components is a mixed metaphor.  The components are not necessarily designed to work together.

So, for example, a typical masonry firebox has a damper that is designed to mate with masonry flue tiles.  A typical metal fireplace firebox has a flange that is designed to mate to metal flue pipes.

If you mix them up, you are going to have to fabricate something (aka: rig up some E36 M3) to make the transition.  This is likely to be the failure point in the event of an incident.  I doubt you will find an inspector anywhere who would sign off on a mixed metaphor approach.

Additionally, you CAN'T put a masonry firebox on a wood floor structure.  At all.  Even if the floor was capable of holding the weight (it's not), wood expands and contracts, and masonry does not.  At some point you would have gaps developing between the two materials, which could be a fire hazard.

A masonry firebox does not sit on a wood floor.  The floor is cut out, and footings are installed at the ground level.  Masonry support is built all the way from the ground to support the firebox and transfer the load to the footings, not the wood floor structure.  The wood structure free-floats from the masonry fireplace support entirely.

Does that make sense?

You are right a masonry fireplace needs it’s own footings separate from the housing foundation.  Due to the weight and as you said wood shrinks and swells based on humidity. Masonry does not.  

It can be dealt with but not easily and as you say getting a building inspector to sign off would be nearly impossible. 

My only objection to a metal fireplace is the fire eventually will weaken the steel and thus it has a real definite lifespan. Too many factors to put an actual number on it but we’re all familiar with it. Since we all do a lot of metal work. 

As Ive repeatedly said I’m a scrounger. When something is too expensive I find affordable replacements or alternatives.  I think that’s at the very core of being a GRMer 

the picture shows that wood and stone can co-exist. That stonework on Timbers has been in place more than 15 years  close examination will  prove crack free  Actual stone, actual wood Timbers 

SVreX said:

In reply to Curtis :

To be honest, I have never seen that nor considered it.

Combining masonry firebox with metal flue components is a mixed metaphor.  The components are not necessarily designed to work together.

So, for example, a typical masonry firebox has a damper that is designed to mate with masonry flue tiles.  A typical metal fireplace firebox has a flange that is designed to mate to metal flue pipes.

If you mix them up, you are going to have to fabricate something (aka: rig up some E36 M3) to make the transition.  This is likely to be the failure point in the event of an incident.  I doubt you will find an inspector anywhere who would sign off on a mixed metaphor approach.

Additionally, you CAN'T put a masonry firebox on a wood floor structure.  At all.  Even if the floor was capable of holding the weight (it's not), wood expands and contracts, and masonry does not.  At some point you would have gaps developing between the two materials, which could be a fire hazard.

A masonry firebox does not sit on a wood floor.  The floor is cut out, and footings are installed at the ground level.  Masonry support is built all the way from the ground to support the firebox and transfer the load to the footings, not the wood floor structure.  The wood structure free-floats from the masonry fireplace support entirely.

Does that make sense?

It does make sense.  A few of the lightweight masonry boxes I looked at (specifically Mason-lite) talked about a steel base frame and mentioned that it needs to be X" away from combustibles. They also mentioned a kit you could get to attach to a 12" insulated vent. It confused me because they made it sound like you could install it much like a steel box but evidently not.  From their website:  "Allowed for multi-story combustible floor installations."  

and this pdf of installation schematics

and this owner's manual has a whole section on installation on combustible floors and insulated steel flues.

See my confusion?

 

As Ive repeatedly said I’m a scrounger. When something is too expensive I find affordable replacements or alternatives.  I think that’s at the very core of being a GRMer 

 

Much truth.  Today I'm on my way to pick up 30 free pallets (actually, the brewery is giving away a $100 gift card with them because the city said they have to go to avoid littering fines) in the hopes that the weathered pine can become a floor or an accent wall or a coffee table. 

Most pallets are oak. 

In reply to SVreX :

Plus removing the spiral twist nails is extremely difficult to do. Especially if they are older pallets. What happens is the tannins in oak attack steel and cause it to rust.  Not to mention the grit sand and debris ground into them damaging your planner blades etc. 

Thats why I started to use pallets as fuel. A few minutes with a Skil saw turned the pallet into fireplace sized chunks of wood.  Free of the bark oak burns leaving very little ash 

nails collect and a strong magnet separates the nails from the ash for recycling. That’s the easy way to remove nails from a pallet.  

In reply to Curtis :

You’re a tough sell. 

Ok, first off I’ve never done a Mason Lite system, and know nothing about them. But let’s look at that owner’s Manual. 

The part you are looking for is on page 16 and 17- Supporting Floor Systems. Particularly look at Table 1- weights. 

First notice that they take NO responsibility for the supporting structure, and recommend a structural engineer.  That means it’s YOUR problem.

The smallest unit they show weighs 1431 lbs, and is 7.2 SF. The biggest one is 2662 lbs and is 13 SF. So both are approximately 200 lbs per SF.  PLUS the weight of the stone facade, flue  pipe, framing, etc. 

Stone is about 160 Lbs per cubic foot. If your facing is 4’ wide and 8’ talk and 4” thick, it will weigh 1700 lbs. That’s an extra 170 lbs or so per SF.

Modern engineered floor systems are usually designed to handle about 40 lbs per SF live load. I GUARANTEE your 1920’s vintage stick built floor system is less. 

So you are trying to put over 370 lbs per SF on a floor that is designed to hold about 30 lbs per SF. 

Cant be done. 

They are telling you it can be installed on a combustible floor without any consideration of the floor loads, and suggesting you hire an engineer to solve the problem. 

My answer is to make it simple. If you are going to install a masonry fireplace, start with new footings. If you are going to try to install on the existing floor, install a metal fireplace. 

You make a compelling argument.  Those numbers look like more than just "add a couple supports." Steel fireplace it is.

You just saved me a couple thousand bucks.

And the properly made steel fireplace will have enough heat management built into it to not burn itself up. Ours is 10 years old and on it's original firebricks.. and door gasket and everything else except the incoming air filter, I've swapped that out a time or two.