Finished my install. How did I do?

[begreen]

I suppose the same reason it isn’t 18” where the straight section meets the wall thimble or where a vertical pipe meets at a ceiling box. Why, I don’t know the answer. Only way around that would be to have a larger ceiling box or heat shield.

View attachment 335839

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Not an issue with double-walled stove pipe.

 

[30WCF]

Not an issue with double-walled stove pipe.

I was just editing to add that mine is double wall, so I have closer clearances, but I think the ceiling box is the same, no?

 

[all night moe]

Use the foam pad and protect it with carpet.

 

[30WCF]

I’m not sure I understand this image. Why wouldn’t the 18” distance apply to the entire 45 degree elbow?That is, shouldn’t the whole elbow right up to the seam where it meets the horizontal section have to be >18”, rather than just 18” from the wall to the lower angle of the 45 elbow?

I’m also considering a through-the-wall installation so I want to understand how to measure the clearances properly.

I suppose the same reason it isn’t 18” where the straight section meets the wall thimble or where a vertical pipe meets at a ceiling box. Why, I don’t know the answer. Only way around that would be to have a larger ceiling box or heat shield.

View attachment 335839 View attachment 335840

Not an issue with double-walled stove pipe.

I was just editing to add that mine is double wall, so I have closer clearances, but I think the ceiling box is the same, no?

I suppose what I’m suggesting, and correct me if I’m wrong is when @MaybeErnie asked why I didn’t include the horizontal section in my calculation of the 18”to combustible is because I don’t suspect it is include as it approaches the adapter on most set ups, vertical or horizontal.

I’m making a guess here, but I doubt this is 18” regardless of if cement board or drywall is screwed to the studs.



And the only way to get 18” would be to use a deeper, insulated thimble, like so…



So, I what I meant to reference, and am asking clarification on now, is on many single wall set ups that have small wall thimbles/ceiling boxes going through a wall or ceiling, is the pipe that is perpendicular to the wall measured the same as a parallel run?

 

[MaybeErnie]

And the only way to get 18” would be to use a deeper, insulated thimble, like so…

Yes -- that is exactly what I was wondering about!

I see a lot of descriptions and images where it appears that the last sections of stove (connector) pipe, do not adhere to the specified 18" clearance rule from walls/ceilings. Then it appears that the only way to actually achieve strict compliance would be to use double wall pipe for those sections. However, I'm a little unclear as to whether those ending sections would need to be double-wall stove connector pipe or Class A chimney pipe. I'll check but I think clearance for double-wall stove pipe is 6", right?

And thanks to you folks for helping me sort this out in my head before I buy stuff!

 

[MaybeErnie]

An afterthought to my post above:

From what I can tell from descriptions/images of installs, it seems like the primary concern is with sections of stove pipe that run parallel to the surface in question (wall or ceiling). That is, for walls, all vertical runs of single wall pipe must be 18" away, and for ceilings any horizontal runs of single wall must be 18" away. There seems to be less concern for the terminal sections that run perpendicular to said surface, although it is advisable to use double-wall for those sections to reduce clearance.

Am I getting closer?

 

[30WCF]

Yes. 6” for double wall.

 

[stoveliker]

An afterthought to my post above:

From what I can tell from descriptions/images of installs, it seems like the primary concern is with sections of stove pipe that run parallel to the surface in question (wall or ceiling). That is, for walls, all vertical runs of single wall pipe must be 18" away, and for ceilings any horizontal runs of single wall must be 18" away. There seems to be less concern for the terminal sections that run perpendicular to said surface, although it is advisable to use double-wall for those sections to reduce clearance.

Am I getting closer?

I don't know the rules, but the math does tell one that the radiative heat load will decrease with the sine of the "take off angle" from the pipe surface. So walls parallel to the pipe get the full brunt of the load while walls that are perpendicular to the pipe (and the heat reaches it by having a less than perpendicular take off angle) will see a decreased heat load.

 

[MaybeErnie]

That makes intuitive sense and seems consistent with how folks are implementing the codes

 

[crstrode]

I don't know the rules, but the math does tell one that the radiative heat load will decrease with the sine of the "take off angle" from the pipe surface. So walls parallel to the pipe get the full brunt of the load while walls that are perpendicular to the pipe (and the heat reaches it by having a less than perpendicular take off angle) will see a decreased heat load.

Don't forget that heat energy at the wall is a function of the square of the distance from the source.

Now: go find a government inspector that can grasp those concepts and is equipped to calculate without removing his socks.

 

[begreen]

We’re got very hyper dogs that like to dig in with their nails. Not sure the foam would hold up. But it’s sure cheap!

A large rag rug could be put down for looks and for the dogs. Just remember the hearth clearance requirement for the stove.

 

[stoveliker]

Don't forget that heat energy at the wall is a function of the square of the distance from the source.

Now: go find a government inspector that can grasp those concepts and is equipped to calculate without removing his socks.

I agree. But his point was that the absolute distance from pipe to combustibles was less than 18" for a single wall pipe entering the wall with a standard thimble.