Jotul C450 Hearth R-Value

[Moosehead2185]

I have installed a Jotul C450 insert in to my fireplace and I will need about 6" of hearth extension to meet code. (Stove sits a couple inches proud of the fireplace which is slightly raised above the wood floor). The manual says that I will need a hearth extender with an R-value of 2.92. This seems significantly higher than any pre-made hearth extender I have found on the market.

I found this conversation on here but they talk about making one yourself.
https://www.hearth.com/talk/threads...arth-extension-on-jotul-kennebec-c-450.25453/

Anyone know of one that can be bought pre-made? Or tips on an easy build to make it to the manual requirements?

 

[begreen]

You're right, that is a very stiff specification. Yoder makes a 12" x 48" extension and they will customize protection to your spec. If you don't want to make your own I would contact them.
(broken link removed to http://www.hearthclassics.com/thermal_protection_thermashield_xtreme.php#anchor_floor_protection_sys)

 

[Moosehead2185]

You're right, that is a very stiff specification. Yoder makes a 12" x 48" extension and they will customize protection to your spec. If you don't want to make your own I would contact them.
(broken link removed to http://www.hearthclassics.com/thermal_protection_thermashield_xtreme.php#anchor_floor_protection_sys)

Thanks for the link! I really only need the extension to be about 8" x 40" wide so maybe they can do something for me. It just seems like overkill since I have my insert on a raised (4") hearth above the wood floor. I don't really understand the need for R=2.92 on that wood flooring area. It seems like I am going to have to have a 2"+ thick cement board and Durock on the floor.

 

[begreen]

It would take 1" of Micore 160 and a top layer of 1/2" Durock to achieve R=2.91. Add tile on top and you would be good to go. You might want to contact Jotul and see if the 4" rise over the floor level reduces the R requirement considerably. That might help qualify a type 2 extension pad.