Flue Systems for Cubic Mini

 

Cubic Mini Wood Stoves is a small stove manufacturer based in Canada.  Their small Grizzly stove and even smaller Cub stove are popular choices for very small spaces, or spaces that don't need very much heat.  Since Cubic Mini only offers double-wall pipe for their stoves and no accessories, third party parts are necessary for a safe installation.

Note:  Tiny Wood Stove is not affiliated with or endorsed by Cubic Mini Wood Stoves.

 

Where can I get a roof vent, trim plate, or pipe boot to fit Cubic Mini pipe?

We don't recommend penetrating your roof with Cubic Mini pipe for reasons we'll get into shortly.  However, if you decide to do that, please be aware that our 3" roof vent, trim plate, and pipe boot are meant to fit our 3" insulated pipe, which is 5" outer diameter.  They will not fit Cubic Mini's double-wall pipe.

You can find a roof vent that will fit Cubic Mini pipe here, and a pipe boot that will fit a 3-1/8" outer diameter pipe here.  We're not aware of anyone who makes a trim plate that will fit a 3-1/8" pipe.  You would need to fabricate your own.

 

Why not penetrate the roof with Cubic Mini's pipe?

The only acceptable metal chimney types for wood stoves to penetrate a structure are double-wall insulated chimney, or air-cooled triple wall chimney (see NFPA-211 Chapter 5, "Selection of Chimney and Vent Types").  Single-wall pipe and non-insulated double-wall pipe can be used for connector pipe between the stove and the chimney system, but should not be used to make a roof or wall penetration.  

It’s possible that Cubic Mini pipe through your roof would stay cool enough to avoid damaging the surrounding combustibles during normal operation.  But if you have a chimney fire, non-insulated double-wall pipe is less likely to provide enough shielding to prevent the fire from spreading.

Cooler flue gases, however, can also create problems.  In cold weather, non-insulated pipe above the roof line allows flue gases to cool and condense to creosote more readily.  Flue gases condensing inside the chimney can cause excessive creosote build-up and poor draft.

We recommend using the proper insulated double-wall pipe to pass through your roof and everything above the roof line.  This is better for safety, less maintenance, and better stove performance.

 

Can I connect my Cubic Mini to Tiny Wood Stove's 3" flue systems?

Yes!  Our 3" flue systems are a popular option for safely venting a Cubic Mini stove in tiny houses, cabins, vans, RVs, buses, yurts, and all sorts of small spaces.  The Cubic Mini flue flange is a little smaller than a standard 3" pipe, so you'll want to use our Cubic Mini adapter.  If you prefer not to use the adapter, you can hack the pipe a bit to make it fit.

 

If you are using the Cubic Mini Wall Mount

Because the stovepipe in a wall mount configuration is so close to the wall, you can't use any single-wall pipe in a wall mount configuration.  Single-wall pipe requires 18" clearance to combustibles which can be reduced to 6" with a proper heat shield.  Double-wall pipe generally requires 9" clearance to combustibles which can be reduced to 3" with a proper heat shield.  (Note in Cubic Mini's product description: "Our flue pipe require a 3" clearance to combustibles with flue flashing the entire length."  Emphasis mine.)

You can use Cubic Mini's double-wall pipe for your connector pipe between your stove and the insulated chimney pipe, and Cubic Mini's heat shield kit the entire length.  Use our Cubic Mini adapter to connect the top of the Cubic Mini double-wall pipe to our single-to-double adapter below your ceiling.  Then continue through the ceiling with our insulated pipe all the way to the roof vent.

Alternatively, you can attach our 3" insulated pipe directly to the Cubic Mini flue flange.  Use a set of sheet metal crimpers to crimp the inner wall of the pipe to fit inside the flue flange.  We can also do this for you if you note your request in your order comments.

 

If you're using a floor mount, or mounting the stove on a cabinet

Cubic Mini with Tiny Wood Stove Flue Kit
Photo Credit @oneida_journeys

If you have at least 18" between the stovepipe and combustibles, or 6" with a proper heat shield, you can use single-wall pipe.  Cubic Mini doesn't recommend using single-wall pipe with their stove, but in our experience, it works well for limited lengths of connector pipe.  Mount our Cubic Mini adapter on the stove's flue flange, then continue with our single-wall pipe to the single-to-double adapter included in one of our 3" installation kits.

Using our single-wall pipe is especially helpful if you need to offset your chimney from the stove, since you can use a set of our 45 degree elbows with our single-wall pipe.  Cubic Mini doesn't recommend using 45 degree elbows for their stoves, but in our experience, two 45s works fine with an otherwise well-designed flue system.

If your connector pipe goes straight from the flue flange to insulated chimney pipe, you can use Cubic Mini's double-wall pipe instead of our single-wall pipe if you like.  Use our Cubic Mini adapter on top of the Cubic Mini pipe to adapt to our single-to-double adapter.  Then continue through the roof in insulated pipe, all the way to the chimney cap.

Finally, if you want to use an all insulated chimney, you can attach our insulated pipe directly to the Cubic Mini flue flange.  Use a set of sheet metal crimpers to crimp the inner wall of the pipe to fit inside the flue flange.  We can also do this for you if you note your request in your order comments.

 

A note on pipe boots and shingle roofs

Our flue kits include a pipe boot that works great for nonporous roofing materials like metal or rubber.  The base of the boot is flexible, so it can conform nicely to corrugated roofs.  If you have a standing seam metal roof, it's preferable to locate the roof penetration between the seams, so that the entire base of the boot is on a flat surface.

If you have shingles, you'll need a metal flashing that matches the outer diameter of the pipe (5" for our 3" insulated pipe), and your roof pitch.  Pipe boots are not compatible with shingle roofs.

 

How to exit through the wall with a Cubic Mini

We don't recommend using a wall exit with a 3" stove.  In our experience, stoves with a 3" flue outlet are simply not powerful enough to draft reliabily with a wall exit.  You really need a well designed roof exit for a 3" stove like a Cubic Mini.

If you need a very small stove that will work with a wall exit, we recommend the Dwarf 3kW Standard.  The Dwarf 3kW is only slightly larger in output than the Cubic Mini Grizzly, but uses a 4" flue system, and can be installed using our 4" Wall Exit Kit.

 

Need help with your project?

Drop us a line at support@tinywoodstove.com if you need some help picking out your flue parts, or if there's anything else we can do to help with your project.

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