Low chimney clearance

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Hope everyone has a wonderful and warm Thanksgiving!
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here
Status
Not open for further replies.

fisherman73

New Member
Hearth Supporter
Jul 11, 2008
15
southern oregon
I am in the process of constructing a new 2 story home. It is a long story but the planning for the chase through the second story went arry and now we are nearly ready for sheet rock. The chimney is ran and has the minumum air clearance or more for the simpson duratech. The problem that I am running into is with the connection to the stove. My duratech comes out of the first story ceiling 6" but only has a 3" air clearance to the wall. I need to attach an elbow and bring it out away from the wall to the stove. Simpson says I should go to a DVL connector pipe elbow then to the stove but the DVL has a 6" min clearance. I thought that I could use a duratech elbow first then go DVL. Again the problem is that the duratech only comes in 15 and 30 degree elbows and the DVL comes in 45 and 90 degrees. So to use the duratech elbow first I would need to use a 30 and a 15 to make a 45 then go to a DVL straight pipe then the other DVL 45 to the stove. Confusing I know. What do you all think? Get a good heat pump?
 
Can you post a couple shots? It sounds like you need an offset in the DuraTech pipe, above the 1st story to correct the problem and make the DVL run below the ceiling support box a straight shot to the stove flue. Is that possible?
 
I went back to the first post. Is the chase in the picture the box that is against the ceiling partition? If yes, that is definitely wrong. It looks like it should be in front of that box. It's hard to determine clearances from the photo, what are the dimensions of the current chase?
 

Attachments

  • [Hearth.com] Low chimney clearance
    June July 2008 208.webp
    26.4 KB · Views: 229
basically yes the chase is not right. the dimensions are ok at approx 20" square but the problem is above the first floor. The chase through the second floor is too close to the wall. The clearances are all to spec now and it has passed mechanical rough in inspection. It seems that I could just add the duratech elbow to the bottom of my chimney and bring it out. I have 3" of clearance so that would be more than adequate, however the person I talked to at simpson says "no I need to go to a DVL after 6' below the finished ceiling". He couldnt tell me why or why not to use the duratech below the ceiling level. Im sure that it will pass mechanical if I do bring the chimney out with the duratech elbow, but is it safe?
 
The person at Simpson said that because the ceiling support box is a transition piece also. Class A on top, but it is designed for DVL connection on the bottom. Not to mention that having bulky class A in the livingroom would look bad. Do it right or it will always be staring at you as a mistake.

You might call Simpson again and ask if the 6" clearance at the top could be reduced by either a wall shield or a pipe shield until the 6" clearance is met. If they say yes, discuss with the mechanical inspector to see if he approves. It should be safe and what I would do as long as it gets approval. If yes, the pipe shield should be offset from the pipe 1" and only would need to extend down about 6-9". I could be painted black (use Krylon BBQ satin black) to match the pipe.

On the other hand, is your vented wall shield going to extend all the way to the ceiling? If yes, I am not sure if the inspector would grant approval for that reducing the clearance 50%, but it's worth asking.
 
I had the pipe "professionally installed" and paid dearly for it. However I am confident that the installers are not up to par. Instead of using the square ceiling support box they used a roof support inside the chase on the top side of the center floor. There is a fire stop sheild completely covering the floor of the center floor chase, and the proper fire stop and insulation shield in the attic. Because they did this the pipe that extends 6" below the first floor ceiling is just a piece of 6" duratech that we intend to finish with the round ceiling trim collar. I thought that If I used the duratech elbow that I could paint the visable part black and that it would look similar to the DVL. The hearth wall would need to end before the ceiling do to the limited space behind the pipe. I could use a metal shield at the top of the hearth that Im sure I could make astheticly pleasing if necessary. Just out of curiousity why not just run the same duratech all the way to the stove. I think that the polished stainless finish looks better than the black.
 
The support box should be able to be retrofitted. Perhaps they were waiting until the drywall work was done?
 
They way they did it is an acceptable way to install the chimney. Simpson does make a short section of duratech in black which is what they probably should have used for the last piece. We always use the support boxes because I think it gives a cleaner looking install.
 
Status
Not open for further replies.