What is the maximum chimney/flue angle?

[mongobutpawningameoflife]

Hi all, I just joined the forum and searched the archives but didn't see quite what I'm looking for...

Background: Experienced DIYer. I want to build a new corner fireplace in my first floor living room. The second floor is a loft so I have plenty of room for a chimney; however, one side of the back of this corner fireplace is on an outside wall so I'm wondering: can I just have the chimney exit high on that wall at an angle and build the chimney on the outside of the house? and if so, what is the maximum angle that can be used for this flue/chimney?

Notes:
- I'd much prefer to build a direct vent natural gas fireplace which would make this sooo much easier and eliminate the entire angled chimney problem. But our old house had a dual-use fireplace (gas & wood) with a proper chimney, which my wife really enjoyed and would like to replicate. We never burned wood in it and only used it with gas and faux logs but what she really liked about it was the unobstructed open firebox, and I told her that a direct vent would mean a sealed glass firebox. So I'm trying to see if there's a way to make the dual-use fireplace work.
- I plan to pull all the necessary permits for this project. This phase is just a fact-finding mission.

 

[DAKSY]

All gas units are different. You need to refer to the installation manual for venting requirements.

 

[mongobutpawningameoflife]

Thanks for the feedback. I think I got too specific with my question. I'm asking more of a "in general" kind of question, like is this even feasible or is it a dumb idea? Do chimneys ever get built this way?

Thanks

 

[DAKSY]

Chimneys DO get built this way, but once again, you need to know what the manual says for chimney (or venting) requirements are for the specific firebox you intend to install.

 

[bholler]

Thanks for the feedback. I think I got too specific with my question. I'm asking more of a "in general" kind of question, like is this even feasible or is it a dumb idea? Do chimneys ever get built this way?

Thanks

Are you talking about building a masonry fireplace or using a prefab unit?

 

[mongobutpawningameoflife]

A prefab unit. Like I said, we don't intend to burn wood in it, but we do want an open firebox (and NOT vent-less) so I'm assuming we'll need a full roof-height flue of some kind.

At this point I'm just spit balling ideas but I wanted to have some basic ideas roughed out before I talk to the local fireplace retailers.

 

[bholler]

A prefab unit. Like I said, we don't intend to burn wood in it, but we do want an open firebox (and NOT vent-less) so I'm assuming we'll need a full roof-height flue of some kind.

At this point I'm just spit balling ideas but I wanted to have some basic ideas roughed out before I talk to the local fireplace retailers.

Yes you will need a full height chimney in that case. You will simply have to follow the fireplace manufacturers instructions. They will vary greatly

 

[Brooks89]

Double check me but Heat and Glo makes the "Phoenix" Unit, an open face (no glass) gas fueled direct vent fireplace that I believe is suitable for a corner installation and can vent horizontally through the adjacent wall. https://www.heatnglo.com/fireplaces/gas/indoor/phoenix-trueview-open-gas-fireplace
The installation manual is available on their website.

 

[mongobutpawningameoflife]

Wow. I looked through the installation guide and that looks like it checks all the boxes for me. The sticker shock got me a little but I'll eat the cost to simplify the build.

I have a couple of Heat'nGlo dealers in my area so I'll pop over there soon and check it out. A big thanks for pointing me to this!

 

[Brooks89]

Wow. I looked through the installation guide and that looks like it checks all the boxes for me. The sticker shock got me a little but I'll eat the cost to simplify the build.

I have a couple of Heat'nGlo dealers in my area so I'll pop over there soon and check it out. A big thanks for pointing me to this!

Glad to help, good luck with your project. It's definitely not on the less expensive side of things!
I've never seen the Phoenix unit in person. I'd be curious about the proprietary 'power vent' it requires and the sound level while it's operating. Let us know your thoughts when you investigate more.
If you don't mind me asking what's holding you back from the glass face involved in direct vent gas fire place?

 

[Lennox65]

Glad to help, good luck with your project. It's definitely not on the less expensive side of things!
I've never seen the Phoenix unit in person. I'd be curious about the proprietary 'power vent' it requires and the sound level while it's operating. Let us know your thoughts when you investigate more.
If you don't mind me asking what's holding you back from the glass face involved in direct vent gas fire place?

The power vent fan is in the horizontal termination cap so the farther away the termination is, the less one can hear the fan.

 

[mongobutpawningameoflife]

Glad to help, good luck with your project. It's definitely not on the less expensive side of things!
I've never seen the Phoenix unit in person. I'd be curious about the proprietary 'power vent' it requires and the sound level while it's operating. Let us know your thoughts when you investigate more.
If you don't mind me asking what's holding you back from the glass face involved in direct vent gas fire place?

The open firebox (no glass face) is a wife request. Personally, I'm fine with or without a glass face, but our last home had a dual-use wood/gas fireplace (with full chimney) and my wife really liked that setup. Meanwhile, my parents had a standard sealed glass direct vent unit which my wife didn't like it as much.

Whatchagonnado... 🤷‍♂️

 

[Brooks89]

The open firebox (no glass face) is a wife request. Personally, I'm fine with or without a glass face, but our last home had a dual-use wood/gas fireplace (with full chimney) and my wife really liked that setup. Meanwhile, my parents had a standard sealed glass direct vent unit which my wife didn't like it as much.

Whatchagonnado... 🤷‍♂️

LOL Good Luck. Let us us know how it works out!