Super Vent And Double Wall

[scra99tch]

Hey,

I have a few questions for this group. Been reading about several things on and off while I was building my hearth. I went with a 1 inch airspace behind durarock and slate tile. Works perfect. I had bought a Waterford wood stove although the thing was nice looking it did not heat our rooms well enough and went through wood big time. I just purchased a Lopi Leyden and so far after one night of burning love it much better stove and heats really well almost too well.

Heres my first question. With a Lowes bought chimney system through the roof and ceiling I have a 5.75-6.00 inch dia connector on top of ceiling. Will I be able to hook a straight (or an elbow) of double wall pipe to it? Even though the connection piece is single walled up to double wall insulated. I realize I have to connect double wall all the way down but am weary about what fits on the SuperVent system.

Another question is my clearances all seem to be within manufacturers, but one is a bit close which is the front clearance. Will that be a major problem with radiating heat on a wood floor? I bought a fire resistant rug, and felt how hot it got last night and there was not a huge difference in temperature directly in front of stove.

I spoke with my fire department and explained what setup I had he mentioned as long as theres airflow on any combustibles I should be fine. While going through the roof the contractor cut through so that the double wall insulated was actually touching one of the rafters. I was able to cut out about .5"-1.0" of material out of the way but manufactures says 2" min. What is your take on this is it safe? The pipe itself does not get hotter than 200F while burning. Is there anything I could place over the gap or should I cut more away?

Thanks

 

[crazy_dan]

If the people who made it say 2" then it really needs to 2". The 2" they want is just in case there is chimney fire.

 

[scra99tch]

Was afraid of that. I'll do my best to chisel away at those spaces with a reciprocating saw.

 

[begreen]

The flue will see lots of different temps over it's lifetime. Don't skimp on specified code clearances. The specified 2" air gap is for a good reason. Wood can pyrolyze over time when exposed to continuous high heat. That drops it's combustion temperature quite a bit. If there is a runaway fire or a chimney fire some at point down the road, you don't want to be finding out what that combustion temperature is, do you?

 

[jtp10181]

Get your contractor back there and make him do it right. It needs to have 2" AIR SPACE clearances all around the Class A HT pipe top to bottom.

 

[babalu87]

Get your contractor back there and make him do it right. It needs to have 2" AIR SPACE clearances all around the Class A HT pipe top to bottom.

Huh?

 

[jtp10181]

Get your contractor back there and make him do it right. It needs to have 2" AIR SPACE clearances all around the Class A HT pipe top to bottom.

Huh?

While going through the roof the contractor cut through so that the double wall insulated was actually touching one of the rafters.

 

[T Osborn]

Selkirk install manuals describe the framing procedure to follow should you encouter the vary situation you are in. DO NOt skimp on the 2" clearance issue.

 

[kieth4548]

I used selkirk and at times when I am running some heat the pipes do get pretty warm. I have about 8-10" of clearance. I'm on the fire department and I have seen some nasty stuff from people skimping by. Don't skimp get the clearance.

 

[scra99tch]

will end up sistering the rafters to get my last 1.0" of clearance. Been a pain in the ass wish this was done before storm collar was glued into place.

 

[Gooserider]

Get the clearance, definitely, but don't just whittle away at the rafter! Do the appropriate framing mods to double up or otherwise reinforce the adjacent framing in an appropriate way so that you have both the required clearances (at a minimum, extra never hurts...) AND have properly restored the strength and integrity of the original structure. While we mostly worry about people setting themselves on fire, having the roof collapse will also ruin your day, so you need to take care of both concerns.

As to your other questions...

You should be able to get an appropriate adapter to connect either single or doublewall pipe to your existing chimney - if Lowe's doesn't have / can't get it, then figure out the brand (I think you said Supervent?) and go to one of the many online vendors that sells it.

In terms of your front clearance... Current NFPA codes call for 18" clearance from the loading door to the combustible floor in front of the stove. This is an increase from the former 16" that was allowed in the US, mostly to make US and Canadian standards the same. Because of the lag in updating stove manuals, most still call for the 16" minimum, and there is some debate about whether the 18" or the 16" number controls, with different inspectors ruling different ways in different areas. A hearth rug is NEVER an appropriate / acceptable substitute for proper non-combustible floor protection, however there are ways to build a hearth extension that are minimally intrusive and look good. What is your current clearance? If it is between 16" and 18" I would definitely talk to your inspector about getting "grandfathered" in. Less than 16" is more iffy, but if you're close you might be able to let them slide, especially since the Leyden is a top-loader, which reduces the risk of flying sparks or logs falling out.

Gooserider

 

[scra99tch]

Hey just noticed your Logo, nice bikes got myself a 2001 Jackal last year been having a blast with it. Its in pieces while I wait for the snow to melt.

anyways I have virtually no clearance to the front because I will not be opening the doors I figure a rug should work just fine.

 

[scra99tch]

But do realize I need the 16 inches.

 

[begreen]

Lay a thermometer on the floor about 10" in front of the stove. Get a raging fire going for 8+ hrs and check the temp.

 

[Gooserider]

Well I have a Cat Encore, which is a similar overall design to the Leyden - I have the code required sheet metal floor protector sheild on the bottom of the stove, which barely gets warm. However if I have the stove cooking, the raised brick hearth gets warm enough to be slightly uncomfortable to stand on w/ bare feet, about like an asphalt sidewalk on a hot sunny day... The slate hearth extension I added in front of it is definitely warm, and that is at or past the 18" point, and 3" lower down than the bricks the stove is sitting on.

Our original stove was a side load only smoke dragon, and the hearth was made for it, raised brick with a carpeted floor in front of it. Estimating where the new stove front was going to end up, I thought I'd have about 12-14", not quite enough even with the old codes. What I did that worked out very nicely was to cut out an 18" wide strip of the carpet, pad and the particle board subfloor, leaving the decking boards in place. I then built back up with a layer of aluminum roof flashing, a layer of Durock cement board, and a layer of slate tiles (to match and existing entry way floor that the extension tied into on one end) - this gave me a WIDE extension, far exceeding codes for just about any stove I'd ever be likely to want to install. However the extension isn't in the way at all since it's even with the height of the carpet. It is wider than needed for code compliance, but I felt it was the minimum I needed to get a good layout on the slate tiles... Turns out the stove was right at 16" on the front clearance when I got it installed, but I'm still glad I put in the extension, as it prevented any issues with the inspector.

Gooserider

 

[scra99tch]

could I wrap the pipe and or rafter with kaowool or something similar? Just a thought, wrapping the pipe may trap too much heat within it but if I went and wrapped the rafter then I would'nt have a problem with heat transfer.

just a thought what you guys think?


I am dreading this sistering process as I am dealing with plaster ceilings and close work space.

Thanks Jim

 

[jtp10181]

could I wrap the pipe and or rafter with kaowool or something similar? Just a thought, wrapping the pipe may trap too much heat within it but if I went and wrapped the rafter then I would'nt have a problem with heat transfer.

just a thought what you guys think?


I am dreading this sistering process as I am dealing with plaster ceilings and close work space.

Thanks Jim

No. The 2" clearance MUST be an AIR SPACE. Insulation will hold heat in and make the over all pipe system get hotter in that area. Hotter than the listed clearances were tested for. Which means the clearances in other pipe sections nearby have increased clearances, but you don't know how far since its not tested that way.

 

[DrivenByDemons]

Just out of curiousity, how hot does the outside of that supervent pipe get on an average fire? I know the 2" codes are based on worst case senario (2100+ F) but say I'm running 600-700 flue gas temp - how well does that insulation between the inside/outside walls of supervent work???

 

[scra99tch]

When I the hottest fire I have had stove was at 550-650 I could not touch the pipe I figured it was around 200F but if a chimney fire starts that would get up probably around 400-600. Thats where wood starts top combust I believe (450).

 

[DrivenByDemons]

Wow, that's a lot higher than I thought it would get. You would think with all that insulation packed between the walls of that stuff it would be a lot cooler than that...

 

[scra99tch]

Thats really only a guess, With hot fires I have been able to just barely keep my hand on it I put a magnetic temp gauge and it got to about 200, although those temp gauges are not super accurate.

 

[Gooserider]

could I wrap the pipe and or rafter with kaowool or something similar? Just a thought, wrapping the pipe may trap too much heat within it but if I went and wrapped the rafter then I would'nt have a problem with heat transfer.

just a thought what you guys think?


I am dreading this sistering process as I am dealing with plaster ceilings and close work space.

Thanks Jim

NOPE! There is a BIG difference between airspace and insulation, and they can't be interchanged like that. Remember that insulation doesn't stop heat transfer, it just slows it down. OTOH, air space allows for circulation that will carry excess heat away from the problem area. Sorry, but that's the way it is, we can't change the laws of physics...

Gooserider

 

[crazy_dan]

Sistering a rafter is a heck of lot easier than building a new house especially if the insurance co. doesn't pay.
Not sure if they could tell after the fact or not.
Why gamble with your home, and family?

 

[ckdeuce]

could I wrap the pipe and or rafter with kaowool or something similar? Just a thought, wrapping the pipe may trap too much heat within it but if I went and wrapped the rafter then I would'nt have a problem with heat transfer.just a thought what you guys think?


I am dreading this sistering process as I am dealing with plaster ceilings and close work space.

Thanks Jim

Honestly, I went through the same thing. Bought houuse with an 8" chimney already installed and I thought I was GOLDEN. Hooked up the new stove, enjoyed it for a few nights.... Then noticed the wall that the chimney went through was warm one night. Huh I thought. Posted a few threads on this site..... And ofcourse everyone was telling me to check it out. Ok, I did. Pulled the boxed structure away form the chimney and guess what.... They has about 1" clearance all the way around and on one side at the very top, I say charred wood. Scared the crap out of me. Long story continues........ I thought "Ok" i moved the stuff that was too close. Well I burned a few more nights, but could jot sleep very well. I thought if they did not care about the clearance there, what about the other areas. Next day, check the floor where it comes through the basement, check the ceiling where it goes into the attic, and climbed into the attic to check where it went throught the roof. Well guess what. All three areas had only 1/2 to 1 1/2" clearance from wood and framing. And all three areas had dark (charred looking) areas on them. Spent a whole day cutting the 2" clearance that the pipe states is needed, then found out that the pipe was to old to had the UL listed 103 HT certification. Long story short....... LAst week I went to lowes and bought a new chimney. Installed it with the proper clearance and fire protection and I now enjoy hot fires without the worry. Bottom line $600.00 in a new chimney = a good night of sleep knowing that my family is safe. The old chimney was warm / hot to touch...... Nothing that "Could ever cause a fire" but after looking at 3 areas of charred wood!! I was scared safe.

On a side note, I would like to thank all of the people who replied to my first few threads. I had the sames kind of questions. Because of the replies I received, my home and family are now safe and enjoying the warmth.

Thanks
Chris

 

[Gooserider]

Good story Cris, glad it had a reasonably happy (albeit expensive) ending.... I thank you for telling us about your experience, and hope we have all learned something valuable from it.

Gooserider