Jotul F45 Chimney Installation Questions

[msal]

Hey guys, I have my new stove sitting in my living room and I think it's about time I get around to installing the chimney...

The stove is a Jotul F45 Greenville, purchased new about a month ago (I posted on here before making the decision!). I plan on doing the installation myself, as I am somewhat handy. I'm ready to start ordering chimney parts but wanted to run it by you folks before I started ordering the wrong things.

A little more info... my wife and I still haven't decided if we will kiddie-corner the stove or run it straight out to save space in the living room. We are probably not going to do any wall protection, as the F45 clearances are already pretty minimal. Also still not sure on whether we will do single or double wall interior pipe for the stove connector. I think double-wall will only let us get closer to the back wall, which isn't a big deal where the stove is at the moment. All in all, I think these decisions only affect what type of connector pipe I buy and the placement of the stove and chimney itself. The chimney parts will all be the same no matter what we choose.

The stove is in the living room. Pipe will go straight up, through the ceiling, through the attic, and then finally through the roof. No elbows or bends, close to the peak of the house so the chimney should be plenty long I think.

So, on to the questions! I went to my local stove shop and priced out chimney pipe, and it was crazy expensive (it would cost more than my stove). I'm now leaning toward DuraVent DuraPlus piping from HD. In particular, they have a kit for around $200 that has everything but the pipe itself. Anyone have experience with this kit? I've read about people not being able to use the roof flashing piece (wrong pitch), having a bunch of extra parts, needing a bunch more parts, etc. I am not sure on the exact pitch of my roof, but it's a shallow pitch (probably standard for a ranch prefab). I'm ready to pull the trigger on this kit and get started, but want to be sure...

Am I going to need some sort of expandable triple wall piece of pipe to connect from the floor of the attic (the ceiling connector) to the underside of the roof connector? I'm guessing I won't be able to get this to exactly align with 3ft segments of triple wall pipe. Does the pipe just slide in to the roof connector from outside instead, leaving any extra sticking out the top of the roof?

Will I get better heat output in the living room if I go with single wall interior pipe rather than double wall? On the other hand, will double wall give me a better draft (keeps the pipe hotter) and thus yield better heat output from the stove?

Any recommendations on a cheap floor pad? The F45 only requires ember protection. I saw one at Tractor Supply for around $60, that was just a plain black mat.

Thanks guys! Questions are all over the place as usual, sorry about that . I also know I have more questions that I'm not remembering, which will probably come up as I work out what I'm doing.

MSal

 

[DAKSY]

I will offer MY $.02 on a couple of your questions & others will get to the rest of them...

I am not sure on the exact pitch of my roof, but it's a shallow pitch (probably standard for a ranch prefab). I'm ready to pull the trigger on this kit and get started, but want to be sure...

Measure your pitch. It is important in the calculations for your chimney height, & also for getting the correct roof flashing, so you need to know EXACTLY what that number is.
Am I going to need some sort of expandable triple wall piece of pipe to connect from the floor of the attic (the ceiling connector) to the underside of the roof connector? I'm guessing I won't be able to get this to exactly align with 3ft segments of triple wall pipe. Does the pipe just slide in to the roof connector from outside instead, leaving any extra sticking out the top of the roof?

There is NO "expandable" section available in any Class A chimney that I've ever seen. That is ANOTHER reason to know the EXACT roof pitch. There is a formula for calculating MINIMUM chimney height & it must be adhered to. Your chimney must extend AT LEAST THREE FEET out of the roof, no matter what the pitch, from the upper side of the penetration.. It must also be a MINIMUM of TWO FEET higher than ANYTHING with in a 10 FOOT distance horizontally. Nearer to the peak of the roof will mean a shorter chimney, but it will NEVER extend less than three feet out. Measure the pitch. Multiply the top number by 10 & add 24 to that answer. This will give you the height - in inches - that your chimney must extend out of the roof.

Others may chime in now...

 

[msal]

I will offer MY $.02 on a couple of your questions & others will get to the rest of them...

I am not sure on the exact pitch of my roof, but it's a shallow pitch (probably standard for a ranch prefab). I'm ready to pull the trigger on this kit and get started, but want to be sure...

Measure your pitch. It is important in the calculations for your chimney height, & also for getting the correct roof flashing, so you need to know EXACTLY what that number is.
Am I going to need some sort of expandable triple wall piece of pipe to connect from the floor of the attic (the ceiling connector) to the underside of the roof connector? I'm guessing I won't be able to get this to exactly align with 3ft segments of triple wall pipe. Does the pipe just slide in to the roof connector from outside instead, leaving any extra sticking out the top of the roof?

There is NO "expandable" section available in any Class A chimney that I've ever seen. That is ANOTHER reason to know the EXACT roof pitch. There is a formula for calculating MINIMUM chimney height & it must be adhered to. Your chimney must extend AT LEAST THREE FEET out of the roof, no matter what the pitch, from the upper side of the penetration.. It must also be a MINIMUM of TWO FEET higher than ANYTHING with in a 10 FOOT distance horizontally. Nearer to the peak of the roof will mean a shorter chimney, but it will NEVER extend less than three feet out. Measure the pitch. Multiply the top number by 10 & add 24 to that answer. This will give you the height - in inches - that your chimney must extend out of the roof.

Others may chime in now...

Hi Bob, thanks for the input! I don't think I was clear regarding the piping inside the attic... I understand I need to get above 2 feet 10 feet around, etc, and can't just connect to the roof piece and call it good. I will definitely measure my pitch now like you had suggested though to make sure my measurements are correct. The part I am wondering about is whether or not I need to connect exactly to that roof connector via 3 ft (or maybe 1ft?) segments, and then start a new piece for outside of the roof and upward, or whether the triple wall pieces just pass through the roof connector. I am assuming the latter since expandable class A triple pipe does not exist and it would be hard to do that without it... Hopefully I am making sense!

 

[DAKSY]

Class A chimney sections are securely attached to each adjoining section, so it does not matter where the seams are, if that's your concern.
Once the lowest section is supported by the support box at the first ceiling penetration, each additional section is stacked & secured to the
one below it. Knowing the pitch & how high the entire stack will be, will allow you to fasten the last couple of sections together before either
pushing them up (DIFFICULT depending on the weight), or lowering them down (EASIER) through the roof flashing, before connecting them
to the lowest sections. Does that help you?

 

[msal]

Class A chimney sections are securely attached to each adjoining section, so it does not matter where the seams are, if that's your concern.
Once the lowest section is supported by the support box at the first ceiling penetration, each additional section is stacked & secured to the
one below it. Knowing the pitch & how high the entire stack will be, will allow you to fasten the last couple of sections together before either
pushing them up (DIFFICULT depending on the weight), or lowering them down (EASIER) through the roof flashing, before connecting them
to the lowest sections. Does that help you?

Ah ok, thanks again! That makes much more sense. If the triple wall pipe had to fasten to the connector (thimble?) on the roof it would be very hard to make sure your placement was perfect so the pipe was the right length, and you were still hitting a floor stud in the attic. That definitely helps, thank you! I'm sure I would have figured this out once I ordered the kit and looked at the parts, but I wanted to know ahead of time... It sounds like I would be better off going down through the connector rather than up when adding the last pieces of pipe.

My other question regarding pitch had to do with the DuraVent kit itself. I've read about others who had to buy a different flashing piece because the one in the kit only works within certain pitch ranges. I'm assuming I will be fine since my roof is not very flat or very steep, but thought I would ask if anyone knew about this. Also, does anyone know if I need to box in the ceiling connector in the stud, or if I can just rely on the two studs only? This will probably be covered in the directions I guess .

 

[DAKSY]

You support box is meant to be supported on 4 sides.
You will probably need to pad out the joists on one side, maybe both, depending on the spacing.
Then cross-members are nailed to the joists & between them, completing the framing & giving 4-sided attachment points.

 

[bholler]

There is NO "expandable" section available in any Class A chimney that I've ever seen.

olympia and several others have them. But in this case there should be no reason to need it.

I would strongly recomend going wit hthe insulated double wall pipe over the triple wall stuff it is a much better product.

 

[msal]

olympia and several others have them. But in this case there should be no reason to need it.

I would strongly recomend going wit hthe insulated double wall pipe over the triple wall stuff it is a much better product.

Could you expand on this? You are suggesting going with double instead of triple chimney (not stove) pipe for the attic/outdoors (not connector), right? I was under the impression that both class A double and triple wall pipe was insulated, and triple was generally considered 'better' due to the extra layer. However, I thought I have read about some triple wall pipe not being insulated. Are you referring to non-insulated triple wall piping? I am in no way an expert, just trying to make sure I understand the differences. If it matters, here is a section taken from the DuraVent triple wall pipe description (on HD.com) which appears to be class A insulated:

This Stainless Steel Triple-Wall Chimney Stove Pipe features two insulating layers consisting of a ceramic blanket plus air space.

Agreed about expandable sections, sounds like I don't need it. I (incorrectly) thought that the pipe section had to end at a roof connector, and a new piece had to start outdoors from the other side of the roof connector.

I'm still unsure if I should go with single or double wall stove pipe for the connector (interior). I need to stare at the clearances for the F45 some more to be sure.

Thanks again!
MSal

 

[bholler]

I was under the impression that both class A double and triple wall pipe was insulated, and triple was generally considered 'better' due to the extra layer.

What you are considering using is insulated but with half the insulation of the double wall. It is safe due to the air space but it does not do as good of a jop keeping the temperatures up in the chimney. It is also larger outside diameter which means larger holes ect. There is nothing wrong with the duravent triple wall but the double wall is better the triple wall is the cheaper option and i personally dont think it is the area to cut costs on..

 

[msal]

What you are considering using is insulated but with half the insulation of the double wall. It is safe due to the air space but it does not do as good of a jop keeping the temperatures up in the chimney. It is also larger outside diameter which means larger holes ect. There is nothing wrong with the duravent triple wall but the double wall is better the triple wall is the cheaper option and i personally dont think it is the area to cut costs on..

Ah, I see. Thanks for the explanation. I was planning on going with DuraVent from HD since it was way cheaper than anything I could get from the local stove shop, and still seems to be pretty well regarded as far as quality is concerned. Is double wall class A pipe harder to come by than triple? I seem to only be coming across triple class A pipe online, and don't see any DuraVent double class A pipe.

Am I correct in thinking that I want to stick with one brand all the way up, or could I use something like the DuraVent kit with non-DuraVent chimney pipe?

 

[bholler]

Am I correct in thinking that I want to stick with one brand all the way up, or could I use something like the DuraVent kit with non-DuraVent chimney pipe?

Yes the whole chimney system needs to be the same and no double wall is not hard to find at all.

 

[bholler]

http://www.woodlanddirect.com/Chimney/Class-A-Double-Wall/?state=13748|13598

Here is the first link i found but there are many more

 

[Woody harrelson]

northlineexpress.com has everything and free shipping. I have ordered from them without issues. i saw the duravent duraplus 6 inch 3 foot sections of stainless steel class A at tractor supply for 100 bucks each! cant beat that!

 

[msal]

northlineexpress.com has everything and free shipping. I have ordered from them without issues. i saw the duravent duraplus 6 inch 3 foot sections of stainless steel class A at tractor supply for 100 bucks each! cant beat that!

DuraVent DuraPlus is class A triple wall pipe I believe, whereas DuraVent DuraTech is the double wall class A. Home Depot has the same pipe you mentioned for $85 (with free ship to store)! I have been reading a lot of good things about this pipe and the double wall seems to be substantially more money (almost double, including the kit). I still need to get up in the attic and measure my pitch, and how much class A pipe I will need before I make a decision. I'll have to compare the total cost of going double vs triple.

Any input on to whether or not I will get better heat output with double vs single stove connector pipe (interior)? Is the only benefit of a double-wall connector closer clearances?

I don't have a hearth and require ember protection only. I'm just looking for a plain black mat I think, nothing fancy. I saw something at Tractor Supply for ~$60 which I think was intended for floor ember protection? Any one have good experiences with these?

Thanks again guys
MSal

 

[Woody harrelson]

The double wall stove pipe will allow closer clearances and also aid in draft by keeping the flue hotter. One downfall is you won't get that extra radiant heat into the room from the insulated stove pipe

 

[begreen]

One downfall is you won't get that extra radiant heat into the room from the insulated stove pipe

Correct. that is actually a plus. The only insulation in double-wall stove pipe is air. It still radiates quite a bit of heat, just not as much as single-wall. But that difference is enough to keep flue gases hotter which means a cleaner chimney.

 

[msal]

It looks like Lowe's SuperVent pipe is actually double wall class A pipe. It's roughly the same cost as the DuraVent DuraPlus triple wall class A pipe at HD. I'm looking at around $200 for the kit, and $85 per 3 foot segment of class A chimney pipe.

Any opinions on SuperVent? From what I've read, these are really Selkirk parts who are pretty reputable. Most of the threads I've found though are a few years old. Any thoughts? I am now leaning SuperVent...

 

[bholler]

From what I've read, these are really Selkirk parts who are pretty reputable

no not selkirk 2 totally different companies. It is good pipe i like olympia's ventis stuff better but it costs more

 

[msal]

A little off topic here, but I noticed a discrepancy in my F45 manual. In writing on pg 11, it says This will result in a minimum floor protector measuring 27" wide x 42" deep. See fig 9. In figure 9, a hearth pad 30" wide x 44" deep is shown.

I know someone in the forums is a Jotul representative, and I've seen threads pop up saying he can be PM'd directly, etc. Of course I can't find any of those threads now when I need them! Anyone happen to know his username? I'm having trouble finding real contact info on the Jotul site, and would rather talk to someone there directly rather than having to proxy through the dealer.

 

[msal]

Hey guys, wanted to get some input on wall protection.

We have decided to fully take advantage of the short clearances on the stove and also install wall protection. My manual just states to follow NFPA 211 guidelines. I am thinking 1/2" Durock with 1" spacers. I helped a friend put some of these up a long while back and we used little bell shaped spacers that you put each screw through to keep the airspace behind the durock. I'm not sure what these are called, but that's what I had in mind. Since we are going to be tight on money once we install the chimney (and running out of time before the winter), we are thinking we will leave the walls plain durock for now, and tiling over the durock next spring/summer. Here are my questions!

1. Is it OK to leave the durock exposed like that without tiles for the winter?
2. I've also seen 1/4" durock... does it matter if I go with 1/2" or 1/4"? I haven't read as much online about 1/4" so my gut tells me 1/2".
3. Are these bell spacers good to use, or is there a better alternative? I am just going off of memory and haven't actually seen them at HD or Lowes.
4. I need to leave room for air to flow in the bottom and out of the top behind the board. How much space should I leave down bottom? Should I just raise the board 1/2" above the floor/pad?
5. Do I need to leave airspace to get behind the boards on the sides, or just the top/bottom? I plan to eventually add some trim around it (after we tile) and I'm wondering if I can block in the sides.
6. Do I need to leave any airspace between boards in the corner (it's a corner installation)? I am thinking yes, otherwise I would have exposed combustibles but wanted to be sure.
7. How high up the wall do I need to go above the top of the stove?

Thanks again everyone .

 

[begreen]

Ceramic spacers, 1" pieces of 1/2" copper pipe, etc. can be used. Or you can cut or snap 36" x 3" x 1/2" furring strips off a sheet of Durock. Double them up to create 1" spacer strips to go on the studs. For a free floating vertical shield I would use 1/2" cement board for the additional stiffness. The air gap is just top and bottom. It's ok to block the sides. The board can contact each other in the corner. It's the vertical air convection behind the wall shield that is keeping the wall behind it cool. Take the shield about 6" over the top of the flue collar unless you are going to use single-wall stove pipe. If single-wall then the shielding may need to go all the way up behind the pipe to 1" before the ceiling. Double-wall stove pipe is much better in this case.
https://www.hearth.com/econtent/index.php/articles/stove_wall_clear
spacers:
http://www.northlineexpress.com/homesaver-heat-shield-screws-and-spacers-pack-of-30-54230-1480.html

 

[msal]

Ceramic spacers, 1" pieces of 1/2" copper pipe, etc. can be used. Or you can cut or snap 36" x 3" x 1/2" furring strips off a sheet of Durock. Double them up to create 1" spacer strips to go on the studs. For a free floating vertical shield I would use 1/2" cement board for the additional stiffness. The air gap is just top and bottom. It's ok to block the sides. The board can contact each other in the corner. It's the vertical air convection behind the wall shield that is keeping the wall behind it cool. Take the shield about 6" over the top of the flue collar unless you are going to use single-wall stove pipe. If single-wall then the shielding may need to go all the way up behind the pipe to 1" before the ceiling. Double-wall stove pipe is much better in this case.
https://www.hearth.com/econtent/index.php/articles/stove_wall_clear
spacers:
http://www.northlineexpress.com/homesaver-heat-shield-screws-and-spacers-pack-of-30-54230-1480.html

Awesome, thank you! I have a bunch of 1/2" copper pipe sitting in the basement so I may go that route, not sure yet. Sounds like I have plenty of options. How about the bare Durock - am I ok with leaving that exposed for this winter, and adding tile next season?

Also, we have decided to go with a double wall stove connector. I read in the forums about how with newer EPA stoves you don't get a lot of heat from the pipe anyways, and it sounds like I am better off just ensuring that my pipe stays hot.

 

[begreen]

No problem with bare durock. You could also use sheet metal painted or left plain.

 

[msal]

Now that I'm going ahead with the wall protection, I'm tempted to make floor protection to match and make it look nice for the wife (we only require ember protection). Previously we were going with just a plain black hearth pad. As far as floor protection is concerned, could I just do something like plywood with tile, and some trim? I would think the stove would flex the board and crack the tiles, but people do this all the time without issue right? I don't need durock since I require ember protection only, right?

 

[begreen]

My understanding is that you will get a better bond with the tile to a layer of durock than to plywood.