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cob wall against woodframed wall ?  RSS feed

 
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Ive seen cob structures that flow into the RMH. Bookshelves , little alcoves ,etc. How do you keep this part from becoming part of the thermal mass? I know cob doesn't have any insulating abilities so it would it carry heat to it ? I want to put a cob wall against a wood framed exterior wall so I thought I could insulate the cob wall from the wood framed wall If needed . I also wondered if I could insulate between the cob wall and the thermal battery to keep the heat confined to the bench.

https://s-media-cache-ec0.pinimg.com/736x/79/40/31/7940312cc694bf14b452f4710ff91d69.jpg


If anyone could direct me to some info I would appreciated it.
 
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Hello Don...

I've seen cob structures that flow into the RMH. Bookshelves , little alcoves ,etc. How do you keep this part from becoming part of the thermal mass?



I am not sure that any one would try or want to. Cobb, by its nature is mass form of insulation (U factor instead of R factor) so operates with the "flywheel effect" for both cooling and heating regulation of a space.

I know cob doesn't have any insulating abilities so it would it carry heat to it ?



It really isn't a matter of whether it is insulating or not as it works as a thermal storage battery for both cooling and warmth, unless you are referring to the "bridging effect" that thermal mass insulation suffer from? Thermal bridging is a pitfall of mass insulations but when the mass is large enough this isn't an issue or if the mass is protected by a breathable insulative layer like straw clay slip and/or mineral wool. Cobb (or modalities therein) can actually be designed to operate under both parameters of either insulative or thermal storage. Straw Clay Slip is an insulative cobb matrix, that can be employed in concert with a more "dense" blend to achieve both a "thermal resistance" barrier then alternatively and thermal mass layer as well.

Cobb/adobe also works well with other insulative mediums like mineral wools very well, and combining all three, mineral wool layer, straw clay slip layer and then a dense mix would become a super efficient matrix, and examples similar to this are achieve "net zero" levels of efficiency.

Hope that helped solidify a few thoughts for you...

Regards,

j
 
Don Campbell
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Jay C. White Cloud, yes thank you for clarifying. The bridging effect is exactly what I was referring to. my concern was if it added to the thermal battery that it would cause my benches to change dimensions. I am at a loss at how to figure the wall with the battery when figuring duct length. I would like to have the bench in a L shape, with cob going up both walls. One wall exterior, the other interior. The wall would be thin only for decorative purposes. If it functioned as part of battery all the better !
 
Jay C. White Cloud
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Hi Don,

Post plan and elevation view planes of your design with wall cross sectional elevations and there are many here that can lend some very good advice.

Warm Regards,

j
 
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