Drolet 1880 install - Interior or Exterior Pipe Run

[tcasey]

Hello all:

Been planning my wood stove install (Drolet Escape 1800) for a while now by lurking, was looking for a couple of opinions on a design question.

My wood stove will be installed in the low corner (closer to the gutter) of a cathedral ceiling room, with a clerestory style roof .

I will be using DVL double wall stove pipe, the Duravent Cathedral ceiling install kit, then the applicable amount of of exterior chimney pipe.

I can either:

A) run straight up through the celling above the stove, through the ceiling/roof and up into the chimney. This will probably be simpler, but will result in about 8-10 feet of exterior chimney compare to about 7' of interior stove pipe. Aesthetically it will look better inside, but not so great outside.

B) Run up to the ceiling (with necessary clearances) 30 or 45 elbow to follow the ceiling line, then another elbow to penetrate the roof closer to the ridge, resulting in about 6' of exterior chimney run. This will probably look aesthetically worse inside, but will be cleaner outside.

My questions are:
From a performance standpoint, is it better to have more interior run, compared to exterior?
Will the elbows affect that performance?
A pretty thorough internet search has only revealed to me 45 and 90 double wall elbows by Duravent, am i missing something?

rough sketch attached for reference.

Thanks in advance.

 

[begreen]

Yes, it is usually better to do the longer interior run in double-wall stovepipe. Chimney pipe is expensive and exposed to colder temps which cools the flue gases quicker. 10' of chimney pipe will look like a rocket. Also, the chimney needs bracing at each 5' level above the roof exit, so 10' would need double bracing.

 

[begreen]

Whichever location is chosen, be sure the 10-3-2 rule is honored.

 

[tcasey]

Thanks. Looks like inside it is. My kids would love a rocket on the roof but I think I might want to avoid that.

Thanks for the diagram begreen. Either option will have the chimney within 10’ of the higher ridge so will have to reach that elevation. I may as well run inside, punch up closer to the ridge and have about 6’ on the exterior

 

[stoveliker]

But yes, elbows do affect performance (negatively). The steeper a pipe is, and the lower the number of bends, the better the draft. (There are mfgs who specify a recommended minimum height and add a ft to that minimum for every 90 deg elbow, and 2 ft for every ft of horizontal run.)

Your run won't be horizontal, so I would not be bothered too much by it.

 

[begreen]

At a 45º pitch it should work ok. The Drolet is an easy breather. tcasey, check the stovepipe clearance requirements. DVL needs at least 6" horiz. clearance but 8" vertical clearance is required.

 

[tcasey]

Here’s an idea that came up after mapping it out tonight. The area highlighted yellow in the attached picture is actually attic space on the other side of the wall. Could I come up from the stove., Pass though the interior wall with a tumble and transition to chimney pipe. Then run up to near the ridge line in the attic and exit there?

 

[Riverbanks]

Are you really against going straight up? Think about cleaning, every year, for the rest of your firewood burning days

 

[ABMax24]

Maybe I'm confused, but why do you need 7ft of double wall inside and 10ft outside? The minimum chimney height for this model is 12ft, which should give you roughly 5ft above the roofline. The 1800 breathes very easily, I wouldn't be in a rush to put a tall chimney on it.

Personally I'd run it straight up, way easier to clean the chimney that way too, could do it right through the stove.

 

[tcasey]

Abmax24 my sketch is not to scale but there is no where for me to place my chimney on that roof surface that is greater than 10’ from the higher roof ridge. Therefore if I’m reading the 10-3-2 rule right I have to go at least the 42” to reach that elevation , then an additional 2’ to meet the rule. That’s 5.5’ at the shortest spot, and more as I move closer to the gutter

 

[ABMax24]

Abmax24 my sketch is not to scale but there is no where for me to place my chimney on that roof surface that is greater than 10’ from the higher roof ridge. Therefore if I’m reading the 10-3-2 rule right I have to go at least the 42” to reach that elevation , then an additional 2’ to meet the rule. That’s 5.5’ at the shortest spot, and more as I move closer to the gutter

View attachment 298794

Ah yes, that makes more sense.

I'd still run it straight up, but that's just my preference. Either option should work.

 

[begreen]

Only 30º elbows exist in chimney pipe for an offset so the angle is important.

 

[tcasey]

Thanks for your advice all, however having spent the evening with a tape measure moving furniture it will actually be much better to install the stove on the other side of the ridge. That way we can get up directly to a point near the top of the high ridge. No bends, no elbows no rocket ship chimneys.

Sometimes I forget to Keep It Simple Stupid!

I’ll share some pics when I get building

 

[GrumpyDad]

Thanks for your advice all, however having spent the evening with a tape measure moving furniture it will actually be much better to install the stove on the other side of the ridge. That way we can get up directly to a point near the top of the high ridge. No bends, no elbows no rocket ship chimneys.

Sometimes I forget to Keep It Simple Stupid!

I’ll share some pics when I get building

Great choice .
I installed a stove that required me to avoid a beam straight up. I also want to be a bit away from the ridge vent, enough so that the flashing would fit under there with a bit of shingle above. AND I wanted to make sure I was able to use a telescopic pipe using double wall DVL. Otherwise, I would have needed to be really accurate with where my ceiling support box would have been to make my angle leg using 45's. I cant tell you how much easier it was using the telescopic pipe, getting a rough estimate on how short I could make my angle leg +5 inches, then just installing the ceiling support. Sure there was much more to it than that, but when the stove was in place, chimney in and flashed, it was time to marry the stove to the ceiling support. It took me about 45 minutes and much of that time was sitting there worrying, and arranging my movable scaffolding to better support my install effort. I feel bad for people that DIY for the first time a stove install and dont get telescopic pipe! Include it in your design for sure.

Also I bought a 5' chimney pipe and was worried about having too much of it sticking up and looking weird. After it goes through the roof Im actually 6" above the advised height. Best advice I can give you is to get that ceiling support box SQUARE/LEVEL/PLUMB! IF you are sure you did that and dry fit your chimney into the support box, and it doesnt look level and plumb all around, your flashing is probably pushing it off a bit. IN my case, I needed to trim the shingles a bit to go around the rounded part of the flashing a bit more. I trimmed and it still wasnt enough so I trimmed another 3/4" of shingle away and wallah, it was perfecto. Sealed with solar 900....done.

 

[tcasey]

Great choice .
I installed a stove that required me to avoid a beam straight up. I also want to be a bit away from the ridge vent, enough so that the flashing would fit under there with a bit of shingle above. AND I wanted to make sure I was able to use a telescopic pipe using double wall DVL. Otherwise, I would have needed to be really accurate with where my ceiling support box would have been to make my angle leg using 45's. I cant tell you how much easier it was using the telescopic pipe, getting a rough estimate on how short I could make my angle leg +5 inches, then just installing the ceiling support. Sure there was much more to it than that, but when the stove was in place, chimney in and flashed, it was time to marry the stove to the ceiling support. It took me about 45 minutes and much of that time was sitting there worrying, and arranging my movable scaffolding to better support my install effort. I feel bad for people that DIY for the first time a stove install and dont get telescopic pipe! Include it in your design for sure.

Also I bought a 5' chimney pipe and was worried about having too much of it sticking up and looking weird. After it goes through the roof Im actually 6" above the advised height. Best advice I can give you is to get that ceiling support box SQUARE/LEVEL/PLUMB! IF you are sure you did that and dry fit your chimney into the support box, and it doesnt look level and plumb all around, your flashing is probably pushing it off a bit. IN my case, I needed to trim the shingles a bit to go around the rounded part of the flashing a bit more. I trimmed and it still wasnt enough so I trimmed another 3/4" of shingle away and wallah, it was perfecto. Sealed with solar 900....done.

View attachment 298808

Thanks for the advice grumpy. I actually read your thread to get some ideas and yours came out great

 

[tcasey]

Thanks for the advice grumpy. I actually read your thread to get some ideas and yours came out great

Hello all:

Id thought i take the time to share my finished install as a thanks for all the advice, and helpfully to help future DIYers:

-The straight up chimney install was aweseome, made connecting the stove pipe a piece of cake.
-The hardest part for me was cutting and installing the through ceiling box. i destroyed a pair of Home Depot snips and the replacements werenot much better. Also i bent the ceiling trim piece a little screwing it in.
-Despite exceeding all the manufacturer and code clearances, my AHJ required a heat shield. I had a local metal shop bend a piece of 24ga steel, then i covered with cut cement board and a mantel. Even now everything is beyond celarances but its a nice peace of mind item. It was my wifes idea to do it like that and i have it admit it looks fantastic, i was just going to spray paint th emetal shield to match the wall color
-I followed the usual rite of passage of new burners and purchased a cord of dry wood that was neither fully dry, nor a full cord! Lesson learned.
-This is a Drolet Escape 1800, it heats the large kitchen amazingly and at night we open the bedroom doors and the heat spills in nicely. Still working on fans to push the air around but our Nat Grid gas bill has been cut and half.
-My first few fires were nice cute little campfire looking things. With the installation of a stove pipe probe thermometer i realized i was burning way to low. Now i start larger fires and let heat crank.
-My low inital temps and wet wood have definitely led to some cresoote build up. I cleaned it twice now with a sooteater and the thing works great.

Overall i love the Drolet, the heat it provides and the change in how we view heating our home. We also rearranged our house layout slightly so we are no longer spread through the 1500' space but concentrated in a smaller kitchen /den space that is heated amazingly and is much cosier.

Also never realized chopping wood was so much fun!

Thanks all.

 

[GrumpyDad]

Hello all:

Id thought i take the time to share my finished install as a thanks for all the advice, and helpfully to help future DIYers:

-The straight up chimney install was aweseome, made connecting the stove pipe a piece of cake.
-The hardest part for me was cutting and installing the through ceiling box. i destroyed a pair of Home Depot snips and the replacements werenot much better. Also i bent the ceiling trim piece a little screwing it in.
-Despite exceeding all the manufacturer and code clearances, my AHJ required a heat shield. I had a local metal shop bend a piece of 24ga steel, then i covered with cut cement board and a mantel. Even now everything is beyond celarances but its a nice peace of mind item. It was my wifes idea to do it like that and i have it admit it looks fantastic, i was just going to spray paint th emetal shield to match the wall color
-I followed the usual rite of passage of new burners and purchased a cord of dry wood that was neither fully dry, nor a full cord! Lesson learned.
-This is a Drolet Escape 1800, it heats the large kitchen amazingly and at night we open the bedroom doors and the heat spills in nicely. Still working on fans to push the air around but our Nat Grid gas bill has been cut and half.
-My first few fires were nice cute little campfire looking things. With the installation of a stove pipe probe thermometer i realized i was burning way to low. Now i start larger fires and let heat crank.
-My low inital temps and wet wood have definitely led to some cresoote build up. I cleaned it twice now with a sooteater and the thing works great.

Overall i love the Drolet, the heat it provides and the change in how we view heating our home. We also rearranged our house layout slightly so we are no longer spread through the 1500' space but concentrated in a smaller kitchen /den space that is heated amazingly and is much cosier.

Also never realized chopping wood was so much fun!

Thanks all.

View attachment 307378 View attachment 307379

HA, that's funny. Neither seasoned nor a full cord.
So very true for my area. I call what we get 'mountain cords'. Short of a cord, 1/2 of the splits need resplit at least once.

 

[begreen]

Thanks for the update, tcasey. It's nice to see the final result.