Seeking Help with chimney measurements....

[tlhfirelion]

I am trying to get as accurate a measurement as possible for my chimney. From the top of my chase to the spot where the wall thimble will be is 73". From the top of the chase box there is a small metal flange that is 10" across and literally part of the chase top. This metal flange extends 9" up from the top of the chase. NOT including the 9" piece on top I need approx. 73" which 2 - 36" sections would leave me 1" short. Including the 9" piece, would I want to take the double up and out of the chase and then attach my cap to that?

I have no other option but to use 2 elbows here, 1 directly above the stove and 1 thru the wall thimble that then sends the pipe vertical and out. Is there wiggle room to compensate for and inch or two at the most that I'd be short on this vertical portion? I assume he elbows and what not have an inch or so of overlap correct?

Also, how do I deal with that flange on top of the chase? I will post up a pic in a few minutes showing that piece. If anyone has any links or pictures with a detailed picture or step by step here, I would be appreciative.

Thank you in advance for any help.

 

[Noah]

What brand chimney are you going to be using? Usually in the instructions it say how far it is required to extend above the chase. I'm sure the pictures will shed more light on the question.

For what it's worth, ICC makes an adjustable length piece of chimney to get it a certain height.

 

[tlhfirelion]

Here is a pic looking up the chase to the opening up top. My century stove requires a 6" flue and this hole up top is 10" across. Is it as simple as just using some brackets and screws to hold it to the outside wall and using a good storm collar?

Also upon further examination of my manual It says that a minimum of 15' is required from floor to cap so that kind of answers part of my own question. Don't worry guys I'll learn to check my manual first before posting.

 

[tlhfirelion]

What brand chimney are you going to be using? Usually in the instructions it say how far it is required to extend above the chase. I'm sure the pictures will shed more light on the question.

For what it's worth, ICC makes an adjustable length piece of chimney to get it a certain height.

I was planning on getting the duravent from my local box store. The price seems right.

 

[webbie]

Two issues you are dealing with - one is the height of the chimney above the chase - since the chase has wood frame and wood across the top (under metal, I assume). If this is the case, I have seen 8" as the min. measurement your HT should be above it....

BUT, most stoves need a certain amount of chimney height (total from the stove up) to function properly. On a straight up chimney, this can be as little as 11-12 feet. Some stoves need more to function properly.

This may mean extending the chimney even further (much further) above the chase - or even extending the chase.

As far as supporting the chimney, there are various ways to do so - but it is hard to see everything from afar. One way would be to frame a ceiling or roof support into an area way below the top of the chase and then stack the pipe on top of that. Another would be to use a roof support system such as some brands offer, which allows some insulated pipe to be below and above the support box.

Make sure you get all your ducks in a row before buying chimney. You may need fitting that the box store does not sell.

 

[tlhfirelion]

Two issues you are dealing with - one is the height of the chimney above the chase - since the chase has wood frame and wood across the top (under metal, I assume). If this is the case, I have seen 8" as the min. measurement your HT should be above it....

BUT, most stoves need a certain amount of chimney height (total from the stove up) to function properly. On a straight up chimney, this can be as little as 11-12 feet. Some stoves need more to function properly.

This may mean extending the chimney even further (much further) above the chase - or even extending the chase.

As far as supporting the chimney, there are various ways to do so - but it is hard to see everything from afar. One way would be to frame a ceiling or roof support into an area way below the top of the chase and then stack the pipe on top of that. Another would be to use a roof support system such as some brands offer, which allows some insulated pipe to be below and above the support box.

Make sure you get all your ducks in a row before buying chimney. You may need fitting that the box store does not sell.

Regarding the height of the total chimney, according to my manual and the height of my chase and stove, I would need to be 3' above the top of my chase to obtain 15' from the stove out.

While I'm sure this question has been asked numerous times, what brand(s) would you suggest I look at that has this chase/roof mounting system you are referring too?

I realized something else that may create a problem with this install. The chase, once I close off the wall behind the new stove and out the stone up, is not accessible from the outside. So if I use a clean out box, I can't get access to it to clean it out. How would that change my install?

thank you for your reply.

 

[webbie]

I think metalbestos (Selkirk) and Hart and Cooley (Metelvent) have this "wrap about" roof support.

Although I don't have enough specifics on your projected installation, one way to do it might be to run the insulated chimney down inside the chase and then use a 30 degree and come through the wall at an angle and then another 30 and head down to the stove...something like that. This would only work with a roof support system like I spoke about.

Otherwise, if you are closing it in - you need a TEE - which hurts draft. You also have the cleaning problem (access) that you mention, but there are probably some solutions to that.

I think Selkirks roof support is called an RSP....
something like the enclosed - they you can put pipe on top and a certain amt below.

 

[BrotherBart]

If he comes through the wall with a 30 then dropping a rope and puliing a brush through wouldn't be a problem with the connector pipe removed. If he had two 30s and was enclosed then it could probably be done by pulling it straight into the stove. I do it with one thirty with the stove in the fireplace.

 

[tlhfirelion]

I think metalbestos (Selkirk) and Hart and Cooley (Metelvent) have this "wrap about" roof support.

Although I don't have enough specifics on your projected installation, one way to do it might be to run the insulated chimney down inside the chase and then use a 30 degree and come through the wall at an angle and then another 30 and head down to the stove...something like that. This would only work with a roof support system like I spoke about.

Otherwise, if you are closing it in - you need a TEE - which hurts draft. You also have the cleaning problem (access) that you mention, but there are probably some solutions to that.

I think Selkirks roof support is called an RSP....
something like the enclosed - they you can put pipe on top and a certain amt below.

I don't think I have much of a choice except to use a tee since a 30 degree is not an option for me. There are too many structural beams and unchangeable sections of the house to make that work. Really, my only option here is to go up and straight thru the wall and then straight up the chase. Not sure if 2 elbows can be used that way or if a tee is a must for that situation. If the roof support system is used (like the picture you provided) does that affect what you use to transition from horz. to vert.?

I must admit this portion (the chimney part) of the process is starting to frustrate me. I am having a hard time getting my head around what all I need and where I can get it without getting ripped off. I get so many different answers that I don't quite know how to proceed.