9:12 pitch cape code story and a half bungalow stove install

[Gabriel]

Hello I wanted to know if any one has some pics to help me to understand how high my chimney will be on a 9:12 pitch roof.

I am going to install the stove on the first floor going and go through an unfinished portion of the second floor bungalow thereby exiting at the roof near the outer envelope of the home (IE far from gable).

Quick math says 9:12 pitch so 9"pitch at about 10' = a 90" or 7.5' tall chimney?! This seems too high.

An alternatives would be to run it through the finished bungalow and exit closer to the gable. I do not want to do this as i will need more holes and more hardware.

If i could just see a pick of one on 9:12 slope roof that would help.

 

[DAKSY]

The formula is 10 x the top number PLUS 24"...So your chimney will be higher than your calculations show. 90 + 24 = 114"...

 

[jharkin]

Its hard to follow exactly what you are trying to do - we might be using the terminology differently. I attached a drawing of a prototypical cape, with the knee walls and the unfinished space behind them highlighted.

The "gable" is the triangular end wall of the upper story between the two pitched roofs.

Are you talking about running the stove pipe up through the knee wall space? When you say " run it through the finished bungalow and exit closer to
the gable" do you mean run the pipe through the finished second floor and closer to the ridge?

The formula you used would be the distance from the second floor to the roof penetration. DAKSYs formula is for the distance required above the roof penetration.If you are trying to figure the total height of the pipe from the stove you need to add 3 distances:

Here is an example measured 5 ft horizontally from the eve....

• The distance from the stove flue exit to the the second floor (say its 6 ft = 72")
• The height from the floor of the second story to the roof penetration - this is where your proposed math comes in, you can multiple the number of feet in from the eve times the roof pich top number. So if you are 5 ft from the eve it would be 5*9 = 45"
• The required chimney height above the roof via the 2-3-10 rule (2 ft above any roof within 10ft horizontal with a 3ft minimum), this is the formula DAKSY gave - 114" But note that you might need that full height if you are less than 10 ft horizontally from the ridge (see second image below)

So the total in this theoretical instance from stove to cap is 72"+45"+114" = 19' 4"

 

[Gabriel]

Sorry i mixed up Gable and Ridge. Thank you. You did understand perfectly what I meant thank goodness lol.

yes option 1 is first floor run flue pipe to ceiling support that enters the knee wall space (unfinished) on the second level of the bungalow.

option 2 is to place stove closer to the ridge (entering in the finished bungalow space) ultimately reducing the total length ABOVE the roof penetration line.

So if I am right same lengths of pipe are needed just a question of whether to keep that pipe inside the house envelope (bunglow space) or to be forced to run it outside where it would extend from the roof high enough to meet 10 - 2 requirement. That is a tall pipe sticking up from the knee wall!

third option is chimney liner. chimney here is an 12X8 rectangle. I need a 6" chimney.

overview of my options if I understand....

knee wall install with a tall exposed chimney above roof. or shorter exposure above roof by going through occupied bungalow space penetrating roof closer to ridge line. Finally install chimney liner and make no holes in ceiling or roof. Right?

one last dumb question... can i use single wall black stove pipe inside my chimney as a liner? Thinking this is a no... do i need insulated liner?

Thank you so very much is cold in MI we just got a good snow! Jack frost was late this year.

 

[jeff_t]

This is 8:12. It's about 7.5' above the roof.



And no, you need a stainless liner.

 

[chimneylinerjames]

If you use the chimney, yes you will need a stainless steel liner. Use insulation also, it improves every aspect of burning. Safety, draft, creosote build up, cold starts......and more.

 

[Gabriel]

Thank you all...

A picture is a thousand words. We have a problem with scrap metal thief here and I don't like the idea of flashing that much chimney above the roof.

So I think for now I may install the stove in the bungalow (2nd floor) and run chimney a short length past the ridge. I can always cut another hole and run more chimney downstairs at a later time if I want the stove in the living room.

Now the question is if there would be a way to get the heat down into the other rooms.

I am using a Vogelzang Boxwood stove BX26E the home is 1200 sq feet. I will also need to construct a floor protector as well. Some backer board with ceramic tile hopefully it will be thick enough to provide enough heat resistance.

I will report my progress and probably come up with some more challenges.

 

[jeff_t]

Those boxwood stoves are pretty scary and hard to control. I would never put one in my home.

Another pic for you

 

[Gabriel]

Honestly the idea of fire is scary to me whatever the stove. But can you tell me why the boxwood in particular? It was on sale and well money is tight considering i spent 200 on the stove and that was just one thing
add chimney floor protector supervent chimney kit and ouch!

Some pics... Snowed last night. The home is being rehabbed.

 

[begreen]

There are some issues with these stoves that have left us leery of using them in the home. These issues mostly revolve around cracking and failure of the cheap Chinese castings and crude air control. As a result it is very common to see these stoves on the used market a year later with clear evidence of overfiring. Personally I'd put in a sturdy older pre-EPA stove before putting one in a home. You never know when a failure is going to occur or how bad it will be.

Be sure that the stove has 36" clearance from any combustible and note that the stove has very high hearth insulation requirements and no possibility of clearance reduction.


From the manual:

The stove must be placed on solid concrete, solid
masonry, or when installed on a combustible floor,
on a Type 2 floor protector listed to standard UL
1618 with a minimum R value of 3.0 and a minimum
thickness of 1” or equivalent.

Clearances listed and shown MUST be adhered to
for safe operation of this appliance. CLEARANCES
MAY NOT BE REDUCED BY ANY MEANS.

 

[Gabriel]

Yea not much sure about the r value of backer board with ceramic. The 1 inch I can do...or built that platform over a couple rows of brick allowing air space underneath.

I see what you mean about the stove. I can see the fire in the stove that's clearly not air tight at the seams last time I checked. Guessing this causes funky draft problems that cause other issues.

I noticed that on sites that sell these stoves they have positive reviews I guess there are new to this. Repeated cooling and heating of cheap cast iron with slag I can see why they fall apart.

This stove might be temp one or two seasons... Besides I wanted one with a glass front and a blower but this is what I can afford for now.

Maybe I can line the walls with clay or use that cement for stoves? Sugar on a turd? for a couple seasons not sure if it is even worth the hassle.

I used to build speaker boxes and in a sealed box you want air tight... I assume to control draft the boxwood should be the same. Air tight from flue outlet to the door inlet.

Having said that at some point people were using crappier stoves than these for hundreds of years, we used to think smoking did not harm you either at one point in history lol.

 

[begreen]

With this stove the insulation value of the backer board is irrelevant. There is no clearance reduction permitted. You will need to have this stove 36" from any and all combustibles. And the hearth needs a very healthy R=3.0 insulation. Some folks may have burned in crappier stoves, but then again, some folks left this planet a little early because they threw caution to the wind. Don't end up a statistic. Install this stove with a lot of respect.

 

[Gabriel]

Can anyone help me with a suitable hearth / floor protector?

I have a few ideas...

6' x 5' total size

I was thinking of putting down rows of brick between sheets of backer board. I could then tile over that.

I can leave airspace between the two sheets of backer board or I could fill that space with insulation.

What do you think?

 

[begreen]

Air is a good insulator, but cement board alone will flex. Its needs a more rigid backing to support the weight of a stove without bending. Usually this would be 3/4" plywood. Flexing not good for tile. The grout will crack unless the base is totally solid.

If this is temporary, I'd skip the tiling and just cover it with sheet metal. Space the gap between the bricks close enough to reduce flexing, maybe 12"? Or get a stove with much easier hearth and clearance requirements?

 

[jharkin]

Seems like it might cost less overall in both $ and effort to just dump the boxwood and pick up an Englander......................