I am soon going to begin cutting squares for use in a stacked wall building project. I am considering using ERC. No bug or rot worries there and I think that it doesn't shrink much either.
After we check off the other ninety two things on our to-do list we are also gonna do our pumphouse in cordwood masonry, and if we make it through that alive we might do that inside our TF as infill, without exposing the timbers.
We are gonna use ERC also, although there are other species more preferrable for cordwood, ERC is fine if it's reached the EMC for where it's gonna be used. Too dry is worse than not dry enough, because if the wood is too dry, the wet masonry will cause the wood to expand and crack the walls. It's easier to fill in gaps than to tear down and start over! It's R-Value is not as high as say, loblolly (which we were gonna use but I won't have any kiln dried available in time) which is one of the top 5 species according to Rob Roy, the acknowledged Guru of cordwood.
I have practically all the books, video's, CD's etc. available on cordwood masonry construction if you need some references, I pretty much have a small library on the subject and can save you some time and money by telling you, IMHO, which ones not to waste your money on.
KJ
http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/fplgtr113.htm
Follow this link and check out chp. 3 for some shrinkage numbers, it looks like you are right on the money for which species to use. White Pine is pretty good too.
Ian
Now to begin the task of finding enough cedar that are big enough. Does anyone know where I can find information on how large a log it takes to make a square of a certain size?
The diagonal of the square inside a circle is the diameter of the circle.
Or the square root of the sum of the square of the two sides.
For a 4x4, would be the sq root of 32 which is the sum of 4 *2 +4 *2. Easier to write than to say.
For a 4x4, the diam of the log is 5.66"
For a 5x5, the diam of the log is 7.07"
Whhooops! Just saw the other post asking this too.
Snakman,
Initially I just keyed in on the word stackwall and didn't even notice you are going to knock the slabs off the logs. Why are you doing this?
Years ago I created a spread sheet program where I could enter the width and height of a timber and it would tell me the diagonal, which as mentioned is the diameter of the circle/log needed to create the timber.
I was mentioning this one time, somewhere on the Internet, and some old timer said, just pick up a framing square and measure from one leg to the other, diagonally across and it will tell you the diameter you need.
So you just measure from 8" on one side to 8" on the other side of the framing square and you'll see on your tape that it takes an 11 1/4" or larger log to make a 8x8 timber, and so on.
Hope this helps.
Jim Rogers
Yup, that's what I needed. After all of the geometry calculators I was messing with, the answer comes to using a square. :-\ Simplicity rules!
kevjay, I will be cutting squares and beveling one side. When stacked, it will resemble lap siding on the outside but it will be a flush wall on the inside.
This is cord wood and they used ERC. Looks good so far. Sassyfrass does not dry much and is pretty rot pruff as is caltalpa (SP?)
(https://forestryforum.com/gallery/albums/userpics/10186/DSC01429f.JPG)
Ohhhhhhhhhhhhh you aren't doing cordwood masonry eh? Just stacking square beams on top of each other?
The cordwood folks also use the term "stackwall" one in the same as cordwood. I'm slow Smakman. Ya gotta spell it out fer me. I still might not get what you are doing, but it don't sound like CM. Jes ignore me I can't figure out my own stuff :D
No, not cordwood. Like log without the round sides. I am still thinking about doing a real DD log, but I would need to use pine to make it look good and that means waiting forever for it to dry. Cedar tapers too much. If I were to do log, I would want notched corners. I think they look a lot better than butt and pass but that is a lot of work I don't want to do.
Smakman, it sounds like you are planning to use square timbers like this cabin was built with. They are in the process of cutting timbers to rebuild it now. They aren't using my mill, but it is orangisred at least. :D Incidentally, I built one just like it when I was just in the 8th grade, nothing to it. ;D
http://ashleycountyledger.com/history/national_register/wiggins3.txt
Nothing to it..... You don't know how the projects I start always seem to turn into a more massive undertaking than originally planned. :-\
Isn't this type of configuration highly inefficient (except for labor)? I mean, it doesn't offer much resistance to thremal transfer through your walls, and the benefits of thermal mass would be minimzed in a layout like that.
A guy up in northern arkansaw is offering me 100 4" x 8" x 12' oak logs for $2500. More at the same price if we want 'em, so we could build our shell this way but I hesitate because of the unacceptable R-Value alone.
Although, I think I the beams would be suitable for TF purposes, he says he wouldn't advise me to use them over a 10' stretch for TF purposes as he says they will warp too bad.
He is sending pics in the snail mail (evidently his computer savvy in posting pics is worse even than mine :D) so I can see what I'd be buying. On the surface it seems like a good great price; the forum bf calculator says it's 3200 bf so that works out to ...... $0.78 cents a bf. That seems awful cheap to me. I'll wait for the pictures and decide then ..... that cheap and ya gotta find a use for them I'd think.
So are you totally sold on the stackwall - having considered R-Value etc?
My older copy of the Wood Handbook says that thermal conductivity of wood is 2 to 2.8 times greater along the grain than across it. If I'm reading that right an 8" thick log type wall would be about equivalent to a 20" thick cordwood wall?
The lower density woods usually shrink less and have a higher R value, but less thermal mass. The thermal mass part of the debate is very much climate related, a large mass trying to maintain habitable temperatures in anything other than a temperate average climate is really just an R value equation.
One company, Pan Abode?, made a double thickness wall with an air space out of interlocked smaller timbers if I remember right.
Walls aren't the biggest part of an energy saving plan, although they certainly are one part. Remember most windows are about R-2.
Well, the R value of 8 inches of ERC would be a little over R8 by the tables I have seen. That's about 4 R less than the average frame home is built with here, but it would also be a tighter wall I think, so maybe it would equal out.
To clear things up Smakman, here is a pic of the one I built. ;D
(https://forestryforum.com/gallery/albums/userpics/12331/rh27%7E0.jpg)
Here's some pics of the efforts to rebuild the Wiggins cabin in Crossett. They weren't working today, and I've been trying to meet the sawyer for about a month now. That's when I first heard of him having a mill, oh well, I'll get a chance to introduce myself oneday. These are a little fuzzy, but they show some logs they've squared, some singles they started on, and some cypress lumber.
(https://forestryforum.com/gallery/albums/userpics/12331/rh30%7E0.jpg)
The singles are stack in the center background
(https://forestryforum.com/gallery/albums/userpics/12331/rh33.jpg)
(https://forestryforum.com/gallery/albums/userpics/12331/rh34.jpg)
(https://forestryforum.com/gallery/albums/userpics/12331/rh32.jpg)
That's a nice dogtrot Rockn H.
It looks like they had rebuilt the Wiggins cabin chimneys only to have the cabin burn..bummer. What caused the fire?
I'd like to say that a solid wall is tighter than conventional...but its not. Doesn't mean I don't like a solid timber wall, just that there are many long horizontal joints to be sealed one way or t'other. You do avoid that whole hot button issue about where to put the vapor barrier or how many you have and toxic mold in a studwall :D
One thing to think about is the way a boxed heart cant dries. Usually the edges shrink more than the center (radial vs. tangential shrinkage). Most of the time you wind up with a dried cant that has convex faces. When I'm in that situation I usually run a power planer down the middle bottom of each timber. That removes the hump and puts the bearing and sealing on the outer edges. You can put a sawkerf in that bottom face to encourage any checking to happen there.
Don P, all bricks were made on site with local materials using the same methods the originals were made with. Sounds like a good trick placing a sawkerf on the bottom.
Good tips. Thanks!