Metal Flue near masonry chimney

[04HemiRam2500]

I am dealing with alot of issues with an install for my house. My masonry chimney needs alot of work so I would like to put a metal chimney through the wall and run it about 4 feet next to the masonry chimney. I saw in the supervent packet that it has to be 3 feet above anything within ten feet of the house. Does this include the masonry chimney?

Even though I am not using my masonry chimney at all would the metal chimney next to it have to go above it? I did not want to spend extra money on the piping and for the roof guy kit not to mention install it if I do not need to.

 

[begreen]

The National Fire Protection Association Standard #211 states: “Chimneys shall extend at least three feet above the highest point where it passes through the roof of a building, and at least two feet higher than any portion of a building within ten feet.”

How bad is the masonry chimney? I'm wondering if a stainless liner would be less expensive in the long run. It would look better.

 

[04HemiRam2500]

The masonry chimney has chunks of brick missing and falling out of the top of it. It needs a lot of work.

So if I go with the metal route, it will have to go above the masonry chimney? I thought the code was written only if say my masonry chimney was being used?

Maybe I can remove just the top part of the chimney that sticks out of the house and put a liner in it and have the metal liner come out above the roof. I think that this will not work though.

 

[begreen]

I'd get a few quotes for repairing the masonry. It may cost less than you think. A 2 story external metal flue could end up being $1200 in parts alone or more. A liner kit would be around $400. If the chimney cap can be repaired for $500 you are way ahead and will have a better install, plus you have fixed a defect. (important for resale).

 

[04HemiRam2500]

i dont know about that. the thing has many cracks in the mortar it was built in 1940s and back in the day grandparents cut a hole in bottom base of it for the coal furnace flue. I think that it needs a complete rebuild. let me know if you want to see pics.

also, the code takes place even though the masonry one is not in use?

 

[begreen]

Code has no knowledge of future use. The next homeowner may want to resurrect the old chimney. That said, I don't think this is relevant to the adjacent chimney, but will let the code experts jump in here to verify.

FWIW, with an insulated stainless liner the cracks are not a functional or safety issue unless you are worried about the chimney falling down? If that is the case take it out. It's a 1-2 day job that you can do yourself.

Pics are always welcome. You may be seeing things that we haven't.

 

[kingston73]

Just to give you an idea if you haven't gotten a quote yet, we have a chimney our oil furnace vents through, it was in decently good shape except for the top 2 feet. It cost $1000 to get the top couple feet rebuilt and new flashing put on around it, with a chimney cap.

 

[begreen]

Bump with question. Does the 10-3-2 rule apply to an adjacent chimney (4 ft away) or only building structure like a roof, wall, etc.?

 

[fossil]

Well, it seems to me to be a non-issue. The 10-3-2 rule, as I understand it, is intended to minimize the effects of the structure configuration on windflow, and thus possibly affecting flue draft. Makes sense to me for roofs, gables, walls, & etc., but I don't think a masonry chimney within the 10 horizontal feet is going to affect anything. Truth be told, the flue for my Lopi extends out of the roof less than 10 feet from my existing masonry chimney (like ~18"), and just a foot or so taller.

 

[begreen]

That is my thought as well, but I'm not a code expert.

 

[fossil]

My installation was all new, professionally done, and inspected.

 

[Elle]

I am dealing with alot of issues with an install for my house. My masonry chimney needs alot of work so I would like to put a metal chimney through the wall and run it about 4 feet next to the masonry chimney. I saw in the supervent packet that it has to be 3 feet above anything within ten feet of the house. Does this include the masonry chimney?

Even though I am not using my masonry chimney at all would the metal chimney next to it have to go above it? I did not want to spend extra money on the piping and for the roof guy kit not to mention install it if I do not need to.

I just had a new stainless chimney installed next to my masonry chimney and they did go 3 feet above the top of the last brick. The flue is sticking out of the masonry chimney about 6-8 inches I think, but they did not go 3 feet above that, just the top of the last brick. Not sure if that helps you or not, but that is the way my installers did it.

 

[Ed Williams]

i dont know about that. the thing has many cracks in the mortar it was built in 1940s and back in the day grandparents cut a hole in bottom base of it for the coal furnace flue. I think that it needs a complete rebuild. let me know if you want to see pics.

also, the code takes place even though the masonry one is not in use?

Most metal chimney makers offer a transition plate that would let you reline the masonry chimney part way up, discard the damaged portion, then continue up with metal factory chimney. Depending on if the damage is mostly up top, this could be one answer