Chimney height issue

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  #1  
Old 02-12-18, 05:04 PM
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Chimney height issue

I have a conventional brick fireplace chimney, that more than meets the standard 3-2-10 rule on height requirements for my home. My neighbor is building a monster home, with a flat roof. My chimney will be about 6 feet away from the flat roof soffit overhang.

My current chimney height would be about 32 inches below his flat roof height.

I know that normally most codes would would want the chimney to be two (or 3?) feet higher than a flat roof if it was sticking out of the flat roof. And the chimney needs to be 10 feet away horizontally from a roof structure at its top, mine or anyone elses. Since his roof is flat, if I am say 6 inches higher than his roof, then my horizontal line goes to infinity.

So my question is, given my chimney is at least 6 feet away, if I did a flue extension by the exact 32inches so my flue was the same height (just above) of his flat roof would that be ok?

Is this all about dealing with a downdraft issue, or is it safety for the structures? I have a cedar roof, the neighbour will have a rubber roof, mine is the more flammable roof. The problem is putting an extender much more than 3 feet will just look dumb, and if I did the simple code interpretation I would need a 5 or 6 foot extension. I was planning to have a copper extended chimney pot bolted on as a simple solution. Building the chimney up higher will also probably require a brace as the height would be too high for a freestanding brick structure, and in any event would look out of proportion with the home. I suppose I am trying to just get a bit more height without going crazy and reduce if not solve any functional problems. I am hearing height is more about downdraft than safety. Not sure a flat roof nearby will cause a downdraft problem.

It is just an old fashioned wood burning fireplace, no gas or furnace etc. coming out the chimney.

In my province the govt zoning does not care if a new build zoning height or any other adjustment causes an adjacent property to be out of compliance (my home is compliant with the original zoning). You are supposed to work it out with the neighbor. Such is the world of development excesses. But I would appreciate advice as all the info out there deals with what you should do for your own home, not to accommodate someone elses!
 
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  #2  
Old 02-12-18, 06:24 PM
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I saw a new report about a similar problem. An old low income neighborhood is being gentrified and the older homes are being torn down and tall, boxy mansions are being built in their place. The person I saw had no luck with the building inspections and zoning departments so they got the local news media involved. They ended up issuing stop work orders for the offending houses under construction and they put the burden on the new construction to modify adjoining properties.
 
  #3  
Old 02-13-18, 12:28 AM
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Definitely a new situation for me.

The only example that comes to mind is the placement of well and septic. If your well is already in place near a neighbor's line then that property has to consider your well location. My instincts are saying his tall building cannot create a problem with your existing chimney.


Sounds like you have already talked to your local authorities and made no progress. Might consider the next level of authority, and quickly.


I would hate to lawyer up but a letter to them stating that their building is putting your chimney out of compliance and that they will be responsible for any and all related issues. At some point you need to put them on notice.


As for the local authorities, I'm sure yours function differently than here, but there should be a way to challenge their construction permit, an appeals process or similar. Whatever body approved that building may want to consider your problem.


Bud
 
  #4  
Old 02-13-18, 10:48 AM
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The authorities in Ontario have ruled that altering rezoning rules as is typical for a new build especially for height, does not have to consider adjacent properties that may become out of compliance in any way, hard to believe but true. It becomes a civil matter, and while they say you are to work it out with the neighbour, it also means that if you can't your recourse is with the neighbour through court, and not with the city or other authorities.

This issue arose in the old neighborhoods, with the fire safety authorities not allowing now uncompliant gas furnace chimneys to vent through the chimney. The solution was typically for the small home to install a high efficiency furnace venting out the side of the home, and presumably loosing any wood fireplace option which was often combined with a gas venting liner. Often affected seniors who owned the small homes. The matter was in fact litigated against the city for allowing the zoning changes in the first instance, and the city won, making the matter solely between neighbours.

While I hate the neighbours home plan, the neighbours themselves are actually decent people. They are aware of the problem, and will pay to fix it, I will probably split the cost to have it done to a higher than minimal standard. The issue is what is the actual modification that will put the chimney in compliance, maintain function and not look stupid.

Flat roofs are not common, albeit increasingly so, but chimney rules seem to be for peaked roofs. I can't get a definitive view of what alteration would make me compliant, and I don't want a city inspector to weigh in they are part of the problem and will just say to do something dumb to cover themselves as no one seems to know the rule for the situation I describe. So I really just want advice on what I can do that gives me a proper draft and chimney function. I am more worried about getting a downdraft from not being high enough or far enough away from the adjacent structure, but not sure if that is really an issue.

Will probably put a 40 inch copper cap on and see how it goes.

The bottom line, the city should not allow zoning amendments that put otherwise compliant structures offside. But sadly property rights in Canada are not going in the right direction.
 
  #5  
Old 02-13-18, 12:46 PM
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I can only see one reason why the codes are the way they are. The city does not want to stifle growth. They don't one land owner to be able to restrict development of adjacent properties.

 
  #6  
Old 02-13-18, 01:54 PM
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Just a comment to add to your concerns (sorry), but height isn't the only problem affecting the draft. Exterior chimneys have difficulty dealing with very cold temperatures and in your case you already have a significant exposure. Adding 6' (or however much is needed) will definitely risk draft problems and not just establishing a draft but end of a fire cycle when lots of CO can flood back into a house due to the chimney cooling.

It is complex to explain and not well understood by the wood burning community. The old "open a window to establish a draft" mantra is actually dangerous and extending that chimney will be going in the wrong direction.

Sure sounds like a political decision as opposed to a fair one.


One more thought is what's going to happen when the new neighbor starts complaining about your smoky chimney. We occasionally get an inversion and with many neighbors burning wood you almost can't breathe outside.


Bud
 
  #7  
Old 02-15-18, 02:39 PM
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Great points on height and cooling, and yes we do get well below zero winters which won't help which is when one typically lights the fire. What is generally done to address this, do people insulate the chimney in some manner?
 
  #8  
Old 02-15-18, 03:00 PM
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Most just abandon the use of the fireplace and complain about backdrafting, or follow the bad advice of opening a window (should be below the fireplace to help) and risk the CO issue as the fire dies down. Once the chimney is warm it works, but eventually the fire will die down and the balance between the cold outside and the barely warm ashes will determine which way the draft goes.

They do make chimney top fans to induce a draft, never used one. And possibly a metal liner which adds a second layer of thermal protection.

Still can't believe the politics that is allowing the deep pockets to bully the little existing guys.

Bud
 
  #9  
Old 02-18-18, 06:51 AM
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I have installed chimney draft systems. They work , but are a pain in the butt. Most are noisy and have to be maintained and detract from the buildings look depending upon their location.
 
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