Are you not a chimney professional? I assumed you were by the way you were talkingAha, I just found one of the answers. So in Canada, the ULC S635 for relining does not provide provisions for testing for clearances to combustibles, as there are no tests on the heat transmission of the outer shell of the masonry . So essentially, ULCs635 assumes the chimney is constructed properly and up to code, and only gives clearances to that to code chimney. ULC s640 is much more thorough (and as such likely more expensive to test to).
As such, if the manufacturer only tests to ULC s635 they can only give a clearance to masonry. I did find some more thorough explanation of the standards, and an explanation o but it's not really for public consumption.
Building code is really expensive, I don't even have a copy just some relevant excerpts. You are right the clearance to combustibles for a masonry chimney is in the building code though, IIRC its 2" or 1/2" if its an outside wall. It's not relevant though, if you don't have those clearances you need a new chimney system not just a new liner.
Framing out for Wood Insert
- Thread starter JayLii
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I am indeed. I am not, however, a staff member of the certification agencies that conduct the testing. I am also not on any of the boards which write or contribute to these standards. I only found this answer because on the private area for WETT inc I found a discussion about this same topic, with one of the council members posting a document titled ULC-S640 for grey issues. The thread also mentions that the way this is dealt with is expected to change soon, and ULC S635 and ULC S 640 will stop being two very similar partially overlapping standards.
I did mention at the start there is a lot of confusion about this topic, and I was referring to confusion among professional solid fuel installers, inspectors, and manufacturers. There are no clear answers for most of the stuff we have been discussing, it does not say in 6.1.4 of some document an intact clay liner shall constitute 1" of clearance to masonry for ULCS 635. It is, as I said, simply what the inspectors in this area will accept.
So you are a professional charging people for your expertise. But you dont have a copy of the codes that pertain to the work you do. You are confused about the requirements. And you dont insulate even though you cant tell me how you maintain the 1 inch clearance between the liner and the inside of the chimney required for safety.
I am not an employee of any certification agency or have anything to do with writing codes either. But as a professional i feel it is imperative i know and understand the codes that pertain to the work i do. And i have a copy of the code books so i can look up any i dont know. And i cant understand how a pro could possibly work without a copy of any code books that apply to their feild.
I am not an employee of any certification agency or have anything to do with writing codes either. But as a professional i feel it is imperative i know and understand the codes that pertain to the work i do. And i have a copy of the code books so i can look up any i dont know. And i cant understand how a pro could possibly work without a copy of any code books that apply to their feild.
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Also if code does not allow for the clay to serve as the required clearance you should not assume it is fine even if your local insoectors are ok with it. It may pass inspection but it does not adhere to the minimum safety standard.
Wow, that was pretty rude. My job, as pertains to the wood fireplaces that I deal with, is generally installations. The "codes" as you call them that I was referring to are actually testing standards, they are not rules. They are literally specs on temperature tests for chimney. I have the relevant codes, or excerpts of them but they are hard copies so I cannot link them to you, and even if I could it is illegal and probably a violation of this forums rules so I will not. The "rules" that you seem to think are in some code are in fact the certified manufacturers instructions. These instructions are part of the ULC certification process, which is why I linked them.
I come to places like this to give advice, explore the why, ask questions, and keep myself up to date. I don't mind being challenged, and I was enjoying this discussion prior to your last few posts as much of what you asked is simply taken for granted here and not questioned.
In hindsight the reason you don't need insulation wrap with a clay liner is obviously because it is a working acceptable chimney which conforms to ULC S640. As such the stainless steel liner's clearances aren't relevant as long as it is an appropriately rated appliance for that chimney, the liner just needs to be properly rated to withstand the temperatures. The SS liner is simply for sizing. If there is no clay liner, it does not conform to ULC S640, and must be relined. Suddenly the clearances in ULC S635 apply, and the insulation is required for the 0" clearance. Not the "Where's the damper?" question that a typical customer asks, so forgive my lapse.
Good day sir.
Ok it is not illegal or against forum rules to post codes they are public record. The actual ul standards may be because you have to pay for them (which I think is totally wrong btw but that is a different story) But I am not talking about ul standards I am talking about the codes which are the rules and minimum standards we all need to go by when doing work. And excerpts are not good enough you need the actual code. I agree that for the most part the instructions should be good enough. But after reading through many canadian instructions they are just the same as here. One company says one thing about insulation while another says a different thing. They cannot all conform to code and that means that the ul standards are not applied to the instructions properly or they would all be pretty much the same. That is why I go by code on the insulation issue. here is a link to a page with the applicable codes for us that we go by http://www.rumford.com/code/clearances.html
Yes if it does conform to all codes then no you don't need to insulate. As long as the listing for the liner does not call for it regardless which here most do. But how do you confirm that you have the proper clearances from the outside of the chimney with out doing demo to inspect for that clearance? Or do you just assume it is there. And I still dont see how you can achieve the clearance on the inside.
I will apologize for what I said but you need to seriously look at how you are doing things because you should have all of these answers if you do this for a living. Especially when it comes to insulation and clearance issues that is dealing with peoples lives if you get it wrong it can have dire consequences. The block off plate thing is not a safety issue and is not required by any code so that is not a big deal unless you are the one trying to heat your house with that stove. Then it may be a big deal to you.
SO again I am sorry for being so rude.
I did a little more research and the ulcs640 you site for construction of new masonry chimneys does not cover construction it just tests the lining material. Building code covers the construction of the chimney just like here.
Re: block off plates, the Supreme Fireplace INC Volcano Plus ships with a "circulating chamber" (see attached pic) which I think is a pretty cool design for inserts. It essentially fits into the existing firebox creating an enclosed steel chamber with a vaulted top. Two blowers force the air from the bottom to the back and up, returning out the louver at the front of the surround. The insert comes in through an adjustable hole in the chamber and is sealed up, essentially creating the same affect as a block off plate, but arguably with greater efficiency as the whole insert is surrounded.
For the record, my clearances to combustibles from the firebox are clear. I did use R14 Roxul ontop of the circulating chamber and additionally at the top of the chimney (which I will check next burning season to make sure it is not capturing moisture and contributing to any problems @Kyoufu .)
The one thing I do not have is a consistent 1" gap between the clay liner and the insert, but I don't really see this as being a fire hazard although it might not comply with the ULC S635. The clay liner was in great shape as the fireplace was hardly used. I'm with @bholler on how you would actually ensure your liner would remain 1" from the clay liner... seems impossible.
I still am going to do some more research on wood before burning and I need to get some delivered and figure out storage etc.
For the record, my clearances to combustibles from the firebox are clear. I did use R14 Roxul ontop of the circulating chamber and additionally at the top of the chimney (which I will check next burning season to make sure it is not capturing moisture and contributing to any problems @Kyoufu .)
The one thing I do not have is a consistent 1" gap between the clay liner and the insert, but I don't really see this as being a fire hazard although it might not comply with the ULC S635. The clay liner was in great shape as the fireplace was hardly used. I'm with @bholler on how you would actually ensure your liner would remain 1" from the clay liner... seems impossible.
I still am going to do some more research on wood before burning and I need to get some delivered and figure out storage etc.
But the condition of the clay liners dont matter at all even brand new they transfer heat very well what matters is the clearance from the outside of the chimney to any combustible material.
RobbieB
Feeling the Heat
The clearances to inside masonry actually vary for ULCs635 depending on the brand of liner. Excel is 0" w/o insulation, duravent and z-flex are 1".
As for wood, pick yourself up a moisture meter (make sure it is as seasoned as described) and if you are buying it there is lots on usedvictoria. Otherwise head up to Renfrew or Cowichan with a truck and a chainsaw, lots of slash piles up there generally.
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And that tells you something is wrong how can one liner require 1 inch and another made exactly the same require none. Can you please tell us how would you go about maintaing that clearance you keep referring to. And why do you keep ignoring the clearance to combustibles on the outside
I have a moisture meter and will definitely put that to use. What are optimal moisture ratings before burning? Mayberry this wuestion is best suited for a different thread. Also, can you guys pass me on to a thread regarding thermometer s and what type/where to put it etc?
Thanks for the tips, I have seen quite a few on usedvictoria. A friend knows someone who does $175 a cord which is by far the cheapest I've seen. That's delivered.
It's based on testing, and temperature ratings, so if it's wrong its a problem with the certification process. I agree though, it certainly seems odd.
Obviously nobody maintains a 1" clearance. Even with spacers it's unrealistic, you need to use the 0" products or insulate to meet ulcS635.
Jay: Roughly 20% is the upper limit of what you'd want to it to be for same year burning. A bit lower is ideal. $175 is a great price, though you didn't mention wood type. $200-$300 is the typical range from what I've heard.
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