Cannot figure out how to change my profile info...so I'll just post it here on the intro for now.
We're in Texas, getting ready to cut wood for the cordwood home we plan on building on our land.
Our plan is to build a dog trot cordwood, still unsure whether we'll frame it out first or not. (I'm voting yes)
As of now, we live in a neigborhood with all our "farm" animals, annoying the neighbors, but still legal! ;D
We will be off grid. Small amount of solar, maybe. Still unsure about the water though. We live in the land of oil and gas, and they surround our land. :( Not sure how safe the ground water is due to the wells, so we'll probably be looking into getting city water. We do have lots of natural springs, so we're still considering them...(keeping fingers crossed)
We're not sure, and I've not been able to find any info on it, about the foundation. Pier and beam, or slab? What are some opinions on that with cordwood?
Nice to read everyone's topics and glean information! [cool]
Ok, finally figured out how to change my profile info... ;D
Welcome w*
We do indeed have a local cord wood specialist who checks in a lot. Ernest T Bass is his handle. He seems to be the most versed that I know of. As well as rocket mass heaters.
Thank you, Rick. I've read some of his posts on other threads.
By the way, I like your signature quote.
I've not heard of rocket mass heaters...have to go and search that one out.
When asked foundation preference questions I always first come back with another question. Do you have to have a building permit and inspections? If so, then the next thing you should do is go ask your local building department what foundation types they will approve for your area. That may settle the question right then and there.
If no permits or inspections, then it's time to realize that a pier and beam/girder foundation, as typically done, does not meet any building codes. Some local areas might, nut the vast majority will not. There are also some soil types that are simply completely unsuited to them. Clay soils are one that can be a serious problem. When wet they offer just about zero lateral resistance to movement of the piers. So after the permit question is what is the soil like? If a pier and girder foundation develops a problem the remedy will invariably cost more and take more time than if another better suited foundation was built originally.
IMO, a cordwood building is best built on a full perimeter concrete or concrete block foundation wall with a full perimeter reinforced concrete footing, just like other construction technique; wood frame, straw bale, etc. They are more stable than piers, less chance of uneven settling.
Members can not access their profiles until they have made one or more topic posts. It helps prevent certain types of spam making the job of the admin team easier.
I'm a second vote for a full perimeter foundation. Cordwood houses are heavier than stick framed houses. Also my recollection on cordwood building is that they are recommended as a timber frame shell unless the building is round.
Some projects I have seen.
http://countryplans.com/smf/index.php?topic=9186.msg118224#msg118224
http://countryplans.com/smf/index.php?topic=2410.0
http://countryplans.com/smf/index.php?topic=9849.0
What made you go with cordwood? It has some ups, but also some downs.
Cordwood and straw bale are permitted here in NM but only if they have a structural framework. IE, they count the cordwood or straw bale as filler material only.
Wow! Thanks guys. That was kind of my gut instinct, but I just wasn't sure. On code, we're planning on following for safety, but not planning on getting anyone to sign off on it.
Our soil has lots of sand, due to the many springs. Also lots of iron ore rock. (We're also in red dirt country, so that's mixed in too)
Initially, I looked at many types of construction. I just don't have enough faith in haybale due to our high humidity here. (Usually swimming at 90-95%) Regular construction just doesn't fit the bill monetarily for us. Cordwood, we can do ourselves and it offers a good insulation for in the summer and winter. We don't have very cold winters usually. Like today, it's 70 degrees out, and high humidity, albeit, this is unusual for this time of year, but not unlikely.
That being said, what are some of the down sides to it? I'll be honest, I've not heard too many.
Quotewhat are some of the down sides to it
Like most , if not all alternatives types there is more labor and it takes longer if you count time from when the trees are felled, debarked, dried, and the building completed. ??? You do save on buying factory made materials though.
I assume you already know the ups. There are downsides to every building type. The labor is one. Cordwood is a higher labor building type.
Time is also a factor. The logs have to be as dry as possible, if air drying, this can take up to a year. Think about how long it takes split firewood to dry.
The reason is because of the largest downside inherent to cordwood. The logs are laid with the grain from front to back. They are set in mortar or other rigid material. As wood dries it tends to shrink and crack along the grain. This causes gaps between the wood and mortar and cracks in the mortar. Unlike with a log cabin, when a crack runs along the length of a piece of wood there is more wood between the crack and the outside/inside. If the logs swell, it put a crack/gap in the mortar. The largest complaint from owners is draftiness. Fixing myriads of tiny cracks and gaps. People try to make up for this with fiberglass insulation, softwoods, and caulk. I read people recommend it more for outbuildings and cabins.
Log cabins have similar settling shrinkage gap issues, but they are more difficult in cordwood.
I get much of this from reading books on pros/cons of each building type and reviews from people. I have not personally lived in one or built one. E. Bass could give you better personal insight into building and living in one.
It does save money on the walls, but it is a very small portion of the cost of a house.
Here is a movie by paul wheaton who also posts here. Pretty good footage.
[embed=425,349]http://www.youtube.com/watch?v=j3XRa7SsPQk[/embed]
It gives a close up of some of normal downsides. This person violated one of the more recommended cautions in most cordwood building guides, don't use whole cords. Split the wood. The smaller the pieces, the less cracks form from shrinkage.
Try to find Rob Roy's book: Complete Book Of Cordwood Masonry Housebuilding: The Earthwood Method
http://www.amazon.com/Complete-Book-Cordwood-Masonry-Housebuilding/dp/0806985909
Glad I happened to check out this topic.. :) Yes, draftiness is certainly my biggest complaint... Doesn't sound like it would be a problem where you're building, though. In some ways, having the walls "breath" so easily keeps the air very fresh in the house and can be a nice thing. Sometimes a little too fresh when it's -35 below and windy, but tolerable if you follow standard good building practices. Those who insulate with expanding foam seem to end up with a much more air-tight home, but I'm very green minded and don't like using the stuff and breathing the fumes, etc.
We might be building a round studio this summer.. I'll be curious to see how much less drafty a round structure would be. Being so aerodynamic, the wind is supposed to pass you by instead of penetrate.. That would give you the benefit of breathability without feeling a breeze on your face. :)
Thanks hpinson! I have that one. :)
Ernest-do you think the draftiness is due to not letting the wood cure long enough, or is it from the natural cycle of expansion and contraction?
Thanks for all the info everyone! Such a warm welcome! [cool]
In a heating environment bringing in fresh air from outside and warming it up causes the indoor humidity to crash. For instance, if the outdoor temperature is 40 degrees F with an 80% relative humidity and we bring that air inside and warm it to 70 degrees, the relative humidity drops to 18%. We sense humidity relative to the amount of moisture the air could hold at that temperature. This is a pretty good calc for seeing what happens.
http://www.grow.arizona.edu/Grow--GrowResources.php?ResourceId=186&name=relativehumidity
Fresh air is a good thing but very low humidity cancels out much of that benefit. With uncontrolled infiltration the "draft" is strongest on the day when there is the greatest differential between indoor and outdoor temperature. The coldest day of the year is also the draftiest. If warm moist air is exiting through a crack and meets cold, the moisture in the air condenses on any surface that is below the dew point. If this is an ongoing condition and the wood rises above its' fiber saturation point this can cause mold or decay.
I'm not pro or con on cordwood just some psychrometrics for breakfast ;D
I'd cure down to some average of equilibrium moisture content and use woods with low shrinkage numbers.
Interesting facts, Don.. We don't experience low humidity as we have a large family and a pretty small house, so we generate plenty of moisture. I've never heard of condensation in the walls being a problem with cordwood because of how quickly the log ends wick the moisture through, but I suppose it could be more of a concern with cement mortar.. We used an earthen "cob" mortar, which also handles moisture very well, so we've never had that be an issue.
zanelee; Yes, we were very pressed to build quickly and our logs were only cured for about 9 months, which is like less than half of the ideal drying time. However, in '10 we built a small cordwood barn with the leftover wood we had on hand, and that stuff had air dried for several years. The logs have remained much more tight, but the south wall still had a little shrinkage and you'll still find an occasional drafty log when the wind is really howling.
I really think a strawbale house would be better suited to our climate and I would love to build one, but unfortunately straw isn't an easily acquired commodity around here. There are a lot of things I like about cordwood, but it certainly has a few drawbacks. We went with it because we were able to source almost all of the material from our land and we had many hands to help.
I tend to agree Andrew, I think breathability of materials is a good thing. Uncontrolled infiltration is probably not so good.
Thanks Don, for the link. Interesting...
We'll be cutting from out land, and praying that we have more than we need. (It's not been timbered since the early '70s.) We have to clear for the house, gardens and pastures.... We mostly have pine and cedar. There are a few other types, but not enough of consequence. I'm wanting to use cedar lower on the buildings, mostly because of it's natural pest repellant, then the pine on the rest. And of course large overhangs all around.
My husband would actually prefer that we build a log cabin, but mostly because he likes the looks. :P I do too, but, I'm the practical one sometimes.
Oh, and Earnest...went over to peruse your family's blog. Very nice. Your family sounds alot like ours, except we've not been blessed with all the children we had hoped. You are a very blessed man, in many ways.
Thanks zanelee; my sibs and I enjoy our life. ;)
Sounds like you've got some great resources on your land! Our plot was logged just 20 years ago or so.. The only decent trees left are hard to get to. Another reason we went the cordwood rout, since our trees are too small to build a conventional log home with. To be honest, I'm not (or wasn't) real crazy about the looks of a cordwood wall either. It has grown on me somewhat, though. The "look" really varies depending on how you build, though. I'm partial to lots of wood and less mortar, larger logs (about half of them split) and a slight bass relief of the mortar so the logs protrude about 1/2'', but that's just me. ;)
What type of trees did ya'll use to build with? I'm assuming that you used what you had on the land...
How is that holding up to weather, bugs, etc? Also-are you finding that the ends that don't have a larger overhang (sides) are weathering worse at all?
Aspen. It's kind of a blessing and a curse around here.. No bug problems.. The unprotected walls do show a little more wear; pretty much just color fading or some darkening as Aspen is prone to, but no signs of rot or anything severe after 5 years. We've actually tossed around the idea of covering the outside cordwood with chicken wire and earthen plaster to stop the drafts, but it's really not a big enough issue to warrant a measure like that. It's always a possibility if the logs ever show signs of decay or something though.
w* Zanelee. I see our resident cordwood pro has you under his wing.
We value his experience. :)
Shut up, Glenn. I know nothing. :) ;)
If the shoe fits, it just might be your shoe ;) ;D
Quote from: Ernest T. Bass on February 06, 2012, 09:18:01 PM
We've actually tossed around the idea of covering the outside cordwood with chicken wire and earthen plaster to stop the drafts, but it's really not a big enough issue to warrant a measure like that. It's always a possibility if the logs ever show signs of decay or something though.
Around here the old log houses were clapboarded for the same reason. I've been under the siding on a few where they were covering rot, usually started in a splash zone. It has become fashionable to remove the siding and show off the logs... which a couple of generations ago folks were eager to cover up and hide their humble abode.
Quote from: Ernest T. Bass on February 06, 2012, 10:21:11 PM
Shut up, Glenn. I know nothing. :) ;)
Be thankful I didn't tell her all I know about my prodigy little buddy... :)
Yes, Glenn. Very thankful that Ernest is here. [cool]
It's quite nice to get to talk to someone who's actually done it...
Don_P-splash zones...hadn't thought about that before. Need to walk around our plans and see about that one. Thank you for bringing that up.
Ernest...don't know much about aspen. Is it a softwood? Our local pines are a softwood. (kind of keeping my fingers crossed here) Hope you don't mind all my questions... ;D But even the locals say your the cordwood guru. LOL!
Quote from: Don_P on February 07, 2012, 12:10:36 AM
If the shoe fits, it just might be your shoe ;) ;D
Around here the old log houses were clapboarded for the same reason. I've been under the siding on a few where they were covering rot, usually started in a splash zone. It has become fashionable to remove the siding and show off the logs... which a couple of generations ago folks were eager to cover up and hide their humble abode.
Same thing around here.. A lot of times there are some pretty cool dovetailed cabins with ancient newspapers stuffed between the chinking buried under that awful sawdust fiber board siding stuff..
As far as the technicalities behind Aspen, I'm sure Don knows a lot more about it.. Some people have told me that it is actually a hardwood, being a deciduous tree, but its characteristically more like pine, with fewer knots , more brittle and somewhat more rot-prone. I guess it's a cottonwood?
Technically aspen is a hardwood. There is a great variation in actual hardness of woods in both the softwood and hardwood groups. Balsa is a hardwood. It's actually very strong on a weight for weight basis.
Hmm...never would have thought balsa was a hardwood. Interesting.
Anyone have any thoughts on building with softwoods vs. hardwoods?
If you are going to be purchasing your lumber from lumber dealers or big box stores you will find a variety of softwoods being sold as construction lumber. Smaller mills in the eastern part of the country may have some hardwoods, but as far as I know softwoods are king for framing. All the tables in the IRC are based on softwoods. I'm not sure I'd want to be hand nailing much dried hardwood.
EDIT: Ooops I lost track of the cordwood idea.
You don't really want to cordwood with hardwood unless you live in a very dry climate and put a wrap-around covered porch on your house. The wood expands so powerfully when it takes on moisture that it has been known to bust mortar and lift walls several inches..
Some dry stuff,
A couple of old adages come to mind;
Not all hardwoods are hard, not all softwoods are soft
If you know nothing else about a piece of wood specific gravity tells you more than anything about strength and shrinkage.
The second one is loaded. Amongst thousands of species and billions of individuals, just like people there is a whole lot of variability. So these are generalities.
A denser stick is stronger than a light piece (Hey, there's more wood there!). Typically the denser the wood the more it will move with moisture change, an oak floor will move more than a pine floor (There's more cellulose there!). Now you see the quandry, often the question is where is the best balance of strength and dimensional stability. Being natural, exceptions abound. Some woods with high extractives content have high specific gravity yet low shrinkage, the non wood "stuff" keeps the cells from being able to shrink as much...black locust, mahogany and teak are dense yet do not shrink nearly as much as that density number would lead one to think. Honduran mahogany and sweetgum have similar specific gravity yet mahogany has shrinkage numbers of 3% radial/4.1% tangential and sweetgum is 5.3% and 10.2% respectively...extractives vs the relative lack of. A lifetime of study is woefully insufficient and yet we seem to make do :).
I'd be looking for a wood with low shrinkage numbers so the mortar to wood joint is not gapping or crushing. This is a good place to spend a little time; http://www.woodbin.com/calcs/shrinkulator.htm
Don't underestimate the power of swelling wood, the ancients quarried stone by drilling holes, pounding in wood and wetting it. I've seen swelling wood move walls inches, or in a log wall built with green wood that dries and shrinks the wall can drop inches.
Cedar is neat, naturally pretty dry, durable, stable. Do think about the nature of the extractives in durable woods, they are natural but are not neccessarily good for you. We smell a pleasant aroma in cedar, an insect smells poison. Mr Phyfe and Chippendale were more than happy to use mahogany when they got their hands on it, big beautiful and stable. A number of woodworkers of the day also got what they thought was pneumonia... it was the dust. Locust sends lots of folks into a tailspin, I am sensitized to western cedar.
The right hand sidebar on this page has wood techsheets from the forest products labs;
http://www.fpl.fs.fed.us/research/centers/woodanatomy/index.php
Aspen is a populus as is cottonwood ;)
Am I remembering that Rob Roy has used black locust?