cobwood

I love the look and feel of cob with the wood elements embeded. However, local code says any wood in contact with concrete has to be treated.
I know that white oak has superior durability and have used it in lieu of treated in situations such as in the pump house when I did not want treated wood chemicals around.
Is there danger of rot if the cobwood is not white oak? And is there special treatment of the wood in contact with the cob?
Thanks,

Hello Craige,

Rob and I have had discussions on the history of "Cord wood" or "Stack Wood" architecture for a while. I have been studying it's archetypal history in the vernacular for over thirty years. Hopefully Rob will get to read your post and respond. In the interim, I would suggest, as I so often do, that you not use concrete at all. I have never been a proponent of concrete for most applications, especially the construction of vernacular vintage architecture.

Cobb and lime mortar are the traditional matrix to use, and you can also, "sercumnavigate" around you "local code" nazies, I mean officials, by making the superstructure of the home a timber frame with "stack wood" in fill. All they need to examine, perhaps not always, is the blue prints of your timber frame design, which may or may not require a PE stamp. What you choose to use as a thermal mass matrix and/or insulation would not be germane, as you can insulate anyway you choose.

Good Luck,

Craig Moore : Hopefully you will get an answer from Rob Roy ! I do know that he likes red cedar, if it is cut down,limbed and peeled this year it dries with very little
checking of the wood throughout the year, being ready to use next year ! Hope this fills in a least one of your questions !

For the Future Good of the Crafts ! Be safe, keep warm, ! As always your questions and comments are solicited and Welcome ! PYRO - LOGICALLYBig AL !

My husband and I are building our home. We have decided on cobwood. I have a few questions..and am having difficulties finding answers. we are in central oklahoma..so our acreage is covered in eastern red cedar. By my understanding it dries quickly and rots slowly. So would it be a good wood to use? And I have mostly clay for soil...from the tests I have done it should be good for cob. However...I am unclear if that also means it would be ok for cobwood. Any help would be greatly appreciated.

Hello Miriah,

Your conditions sound close to perfect. Species is excellent for cobwood, and yes if the soils prove viable for normal cobb you should be fine. Please share your progress and post pictures if you can. I will stress that though structural cobb and cobb wood is achievable, and an infrastructure of timbers and beams is a better and sounder structure.

Regards,

jay

Best bit of news I have got in a while. I will try to post a picture
or two.

Keep in mind its just my husband and I building...the kids keep us entertained for this portion. We have a few more posts to set and the trench to dig and fill next.

Rob Roy who has worked together with Ianto Evans to marry Cob to cordwood, usually builds with a core of Sawdust, Sawdust and Clay slip or, Clay slip and Perlite,
(and I have seen rock wool or Clay Slip and hay or just Hay )placed in the center 1/3 -1/2 of the cord wood !

I had a gentleman who reported treating the Cedar bark saved from pealed logs to use it like straw in a Cob mixture ! since then we seem to have lost track of him !
Good Luck !
For the Good of the Craft ! Big Al !

Miriah Glenn : You will want to get a second opinion but usually for housing purposes all the logs are peeled at the same time to make sure that all the drying
has occurred with minimal cracks before the logs are fitted together ! Big Al !

Are the post just set in the ground? What is the purpose of the structure? is there drainage around the perimeter of the architecture?

I realize that pic isnt the best. But some of the posts are free standing at the moment. Others are starting to get cross members added. It has been hot so work is slow. the outer posts are supports for the "wrap around porch". The trench is going next to the inner posts, then the rock for the wall base. You cant tell it but the entire area slopes away from the house. We are learning as we go.