Building in Very Cold Areas

Hello,

I am brand new to all this so bear with the simple questions.

My goal is to buy a tract of land and build a earth bag/berm home. I wanted to go back to Washington state but financially that may not be possible. I currently live in upstate NY and started look at NE Maine. The land is quite affordable and it's actually close enough that we could travel up there for a few days and work on the project while still living here.

My big concern is the winters. I have no doubt the earthbag home would provide us with a warm home, my concern is with the expanding and contracting of the soil during the seasons.

How to you address this?

Thanks for any help.

Interesting question.
I have no experience,but I do know all building materials expand and contract with the weather.
If the building is occupied, that cycle will be less extreme.
In an earth bermed/earth bag  home, tempatures should remain even more constant,after all the thermal mass flywheel effect is a major attraction of these designs.

I'm no expert, but I've heard that heavy mass designs are more suitable for warmer climates, and that in very cold places insulating designs are better.

Gilbert Fritz wrote:I'm no expert, but I've heard that heavy mass designs are more suitable for warmer climates, and that in very cold places insulating designs are better.

If he was planning a freestanding structure, I would agree with you. But if he is going to berm it, like an earthship, it will have plenty of insulation. Winters in the high desert are frigid, and the original earthships of Taos do just fine. I think you'll be ok.

As Gilbert said, mass for hot areas, insulation for cold.  Taos gets a lot of sun and a lot of heat during the day, heating the mass, and then it gives the heat back at night when it gets cold.  In northern climates, like here in Wisconsin, our cold comes with short daylight hours and much less sun.  

Personally, I wouldn't trust earthbag construction in such a wet climate. I can see it working very well in the high desert with close to 0% relative humidity and the bags have a chance to dry out inside. But in a climate where the bags never get a chance to dry out inside, it seems like they'd become huge targets for mildew, mold and frost-heaving. The frost part is solvable with various insulation methods, but it seems like those methods would increase the susceptibility of the bags molding on the inside (trapping moisture even more).

Are there many examples of earthbag construction in wet, cold climates? How do you maintain the balance between not using a moisture barrier and keeping moisture out before the cold season?

Kyle, I understand your point about he moisture, however, we are planning to cover our earth bags inside and out with a layer of mortar. Would this solve the moisture issue?

As long as you let them cure (dry out) first, you should be fine. Proper drainage behind the wall is more of an issue when it comes to moisture, then the bags themselves. I've seen several people build these is Canada, so 8 really don't think the cold is going to be am issue so long as you berm it well, drain it well, and use a thermal break. But I'm ko expert, just obsessive. Lol

Tom: Mortar isn't a moisture barrier, so you should be good on that front (everything I've heard is that in wet climates, don't use moisture barriers). I would just think that the moisture would get into the bags in the fall, and come winter, they'd turn into expanding bags of ice. The problem with letting them cure is that I wouldn't think they'd ever dry out in a wet/humid climate like that. Somewhere like Nevada where it's 0% RH and doesn't rain for 6 months of year makes the curing part easy, but I'd think it would be a challenge in upstate NY with the humidity levels.

The bags will eventually dry out naturally, but up there it could take a couple years. I'm not personally experienced with earth bag construction - less than popular here in VT - do they have to dry before they are load bearing for the roof, especially with the heavy snow loads you'll see up there? That could be problematic.

Have you looked into strawbale construction? That's much more applicable to the northeast climate.  NE Maine is blessed with bountiful wood resources and no doubt you'd be able to find a local sawyer to get some rough sawn lumber.  Build yourself a nice timeframe, surround it with strawbales, plaster it inside and out and you have yourself the beginnings of a high performance building.

If timeframing is not appealing, stick-framing with rough sawn lumber and using strawbales for insulation is another option. Whatever you do I would consider other primary building materials rather than earth bags.

I don't have experience with Earth bag.  Where are all the Earthbag folks any ways ??... . Anyway, my experience in cold climates, where I have lived for most of my life, leads me to a combination of thermal mass, and insulation.  Thermal mass inside the insulation if you have multiple materials, or if you decide to have internal walls made of thermal mass... that is really good.  I have not built my own home yet, but I have taken part in or been hired to build straw bale, cordwood, stone,  Earthship, and log homes.  All have their merits in this climate (which is similar to where you are thinking of heading).  The most important things for you to consider when building such things are often the foundation and the roof, your thermals mass and your insulation.  Give your walls a good pair of water resistant boots and a wide brim hat, and Bob's your uncle; there is less need for worry about moisture then.  Many people go with a concrete or stone or a combo foundation for this reason.  

Good drainage, with landscaping taking the water away from the walls, and french drained or surface drained downslope, is paramount to any good long lasting building.  I would caution using Earthbags for structural walls if you are not confident that they can cure.  In that case, a post and beam structure could support your roof, removing the need for fast curing walls.  Like I said, I have no experience with Earthbags so I can not comment on that.  If the area that you are heading has abundant straw, then bales offer great thermal mass and decent insulation, are fast to build, and are a great workshop oriented work bee type thing to do and people love to learn it.  If your land has lots of trees, you might want to build with logs, either cordwood, piece on piece, or traditional  <-listed by order of difficulty.  

I do not plan to use vapor barriers, though the building inspector might be a bit hard to convince.  The only place I might consider it is in the ceiling.  My own constantly evolving idea for my house involves a concrete foundation, with stone up a couple feet, then cedar cordwood for a few feet, then straw bale for a couple of courses, with a post and beam  or joined timber frame structure supporting the roof that has sheep's wool in it for insulation, and a steel roof to either shed snow fast (steep) or support a heavy snow load (much flatter).  I have ideas to do a solarium on the South side, with a stone and glass wall on it's North side.  With operable windows, the solarium acts like a trombe wall, passively heating the house on low angle light winter days.  My climate, like the one you are thinking of, has many winter days with little sun.  A good knowledge of wood heat and storing that heat in thermal mass, puts you at advantage.  Rocket mass heaters might be your best bet.  I plan to have at least two in my house; one that works in concert with the trombe wall, and one that is part of the kitchen/living room shared wall that can be used partly for cooking.      

Earthships, earth bags, are a HUGE amount of work.  Earth is not a very good insulator so you need really large thicknesses.  I know of one here in Alberta that works, but the backside is built into a hill, and the front side is a greenhouse space.  We have an even colder climate than you do. (Zone 2, 12,000 degree heating days per year) but winters tend to be very sunny.

It is incredible how much difference sun makes.  We have a conventional stick built house with R20 walls, but most of the windows on the south side.  Even when it's -20 C (about 0 F) we build a fire in the morning, let it go out, build a fire in the evening, let it go out.  This week, (near end of October) we are having hard frosts every night, temps of +6-8 C  (26-44 F swing)  and the house is comfortable from solar gain.  I think Maine tends to greyer winters than we do.

Other alternative building techniques:

A: Self supporting strawbale.
B: Infill strawbale.
C: Cob
D: Timber frame + Leichtlehm

Mortar isn't a good surfacing material.  Consider lime based or clay based plasters instead.  Cheaper, easier to work with, and more forgiving.

B and D are probably the easiest and fastest for a home owner to do.  Both have the advantage that you build the roof first.  This gives you a place to store materials out of the worst of the weather. (Snow will blow in, but tarping handles that.

The roof system can start as a pole barn.  You likely have local companies that can do this for you, or connect with the local community, and participate in a couple of raisings to learn how to do it.

If you build the roof much bigger than the house plan, you will have big transition areas -- places that have a roof, but only 1 wall.  Semi-outside areas.  These are where you hang garden tools, store wood.  This is where you hang the deer to clean it, and hang bundles of herbs to dry.  This is the space where the kids can play on a rainy day.  This gives you a big porch to sit in the sun or in the shade to shell peas, pick feathers off of chickens.

You are in a heavy snowfall region.  Make the roof pitch at least 4 in 12 (3 in 12 is normal) and make a metal surface and the snow will slide off.  This is also cleaner if you want to collect rain water.

For less than doubling the cost of the trusses, you can make trusses that give you usable attic space.  You can choose to either insulate the floor and have an unheated attic, or insulate the ceiling, and have a heated space. Roof trusses are not generally a DIY item.  At the very least get an engineer to check your plans.  Insulating the ceiling in a truss is a pain.


Leichtlehm -- literally 'light straw' is a medieval technique used for the filling in european construction.  You make a slip of clay and water.  It's runny -- about like cream.  add to straw and mix or toss until each straw is coated.  You then pack it between boards that you fastened on either side of the timbers.  The straw will absorb most of the water, leaving the clay glueing the straw together.  By the time you have gone around the house once, the first one has set enough that you can move your boards up.

The wall has to dry completely before coating.  Traditionally they used barley straw and the straw had enough grain left in it that the grain would sprout, and the barley would suck the water out of the wall then die of thirst.  The resulting stubble was a binder layer for the lime based stucco.  

The resulting wall is thinner than a straw bale wall

Hi Tom,
I've been (homesteading) in North-Northeast Maine since 1976 (located about 30 miles south from Houlton - where Interstate 95 ends).
Just for a general review - we can count on a few winter nights (sometimes a week of them) of -20 to -25 degree temperatures, and seldom but sometimes -30 to -35 ... though rare nowadays (with our quite notable climate change).
Currently we've been in those La Niña weather cycles (for a few winters) so there are less early winter low temperatures, therefore the ground is not freezing as deeply before the snow cover insulates the ground.
Depending on the location of course - there's generally a pretty high water table here. If anything our water issues are less about shortages and more about providing plenty of drainage for the excess.
For instance at my location, having a home with a cellar could be nearly impossible (unless an indoor swimming pool is desirable).
Presently (all summer) we've been in an unusual drought condition - dryer than I've ever seen it - three feet of water in my 12 foot deep shallow well. Usually it's about 8-9 feet deep and 10 feet deep in spring (mud season).
{I'm single, so that small capacity well has been sufficient - thus far}
Best Wishes ~ Rob

Maybe you could look into using an umbrella system like John Hait uses in his Passive annual heat storage buildings (PAHS). The umbrella would keep your structure dry and help increase your thermal mass.


Jason

Roberto pokachinni wrote:I do not plan to use vapor barriers, though the building inspector might be a bit hard to convince.  The only place I might consider it is in the ceiling.  My own constantly evolving idea for my house involves a concrete foundation, with stone up a couple feet, then cedar cordwood for a few feet, then straw bale for a couple of courses, with a post and beam  or joined timber frame structure supporting the roof that has sheep's wool in it for insulation, and a steel roof to either shed snow fast (steep) or support a heavy snow load (much flatter).  I have ideas to do a solarium on the South side, with a stone and glass wall on it's North side.  With operable windows, the solarium acts like a trombe wall, passively heating the house on low angle light winter days.  My climate, like the one you are thinking of, has many winter days with little sun.  A good knowledge of wood heat and storing that heat in thermal mass, puts you at advantage.  Rocket mass heaters might be your best bet.  I plan to have at least two in my house; one that works in concert with the trombe wall, and one that is part of the kitchen/living room shared wall that can be used partly for cooking.      

can you describe more about how you would build/layer the roof, incorporating the wool?  also, i'd love to hear more about the solarium and the trombe wall working in concert with the rocket mass heater, maybe with diagrams!  lol, asking a lot.  

Look into the zero energy house concepts. They all put the mass (earthbags) inside and a contruction which is very well insulated outside. The bags are for heat storage but are poor insulators. Only because a house is made of earthbags it does not mean it works. Look as well how traditional houses in the area were made, tehre is a lot of wisdom to be found. First collect a lot of ideas and research everything before hopping on a new trend.

This topic hits close to home as my wife and I recently moved from California to Northern Minnesota.  

We want to build a natural home and have been contemplating materials for some-time.  We were originally very drawn to work with Cob, but upon much rumination, we've realized that in cold climates like this the most important factor is insulation.  In the natural materials world this pretty much means Straw Bale, or possibly double-walled cord-wood.  This was a major bummer for us as we have no attraction what-so-ever to working with Straw Bales.  But we've swallowed the pill and are planning to build a concentric circular home with the inner ring being composed of Cob, and the outer ring being Straw.  

I can completely sympathize with your desire to live underground!  I've always dreamed of a deep underground home.  But the idea that an earth brimmed home in deep frost climates will keep you warm is perhaps misconstrued. . .  At least in our area, the frost line in Winter decends 6 feet into the earth!  This means that a house buried in the ground will be essentially surrounded by a massive block of ice - very hard to keep warm!  And heating the inside of the house, the heat will leech out into the earth around it, constantly trying to thaw and fight back against the humongous frozen mass of earth surrounding the house. . . .  unless there is a profound insulation layer.  

If you are drawn to working with bags, you may consider filling them with something insulative, like perlite rich mortar mix, or light-straw-clay?  

Also, if you're not opposed to a few unnatural materials (like the poly-bags) you may want to look into aircrete.  This substance could make both a structural and insulative layer to build into the ground.  I have become very curious if aircrete could be made from other more earth friendly materials like lime~  Very interesting stuff!

Meni Menindorf wrote:We were originally very drawn to work with Cob, but upon much rumination, we've realized that in cold climates like this the most important factor is insulation.  In the natural materials world this pretty much means Straw Bale, or possibly double-walled cord-wood.  This was a major bummer for us as we have no attraction what-so-ever to working with Straw Bales.  But we've swallowed the pill and are planning to build a concentric circular home with the inner ring being composed of Cob, and the outer ring being Straw.  

Also, if you're not opposed to a few unnatural materials (like the poly-bags) you may want to look into aircrete.  This substance could make both a structural and insulative layer to build into the ground.  I have become very curious if aircrete could be made from other more earth friendly materials like lime~  Very interesting stuff!

Have you looked into Lou Host-Jablonski's work?  He shows measurement on this site: http://www.designcoalition.org/StrawClay/research/drying.htm, where R-20 of straw-clay walls become possible.  Please share what you think.  

In regards to others' comments on earth homes....here is an article on the Ontario home: https://www.thestar.com/life/homes/2013/08/02/earth_home_powered_by_mother_nature.html.  It appears they used cistern paint as a vapor barrier on the inside.



In regards to aircrete, the domegaia forum has interesting threads....


http://cellularconcretetechnologies.com/testing/ says:
1.SUBSTANTIAL INCREASE IN R-VALUE/THERMAL CONDUCTIVITY  
a.Official tests results show 50% to 80% more energy efficient and 3 times the R-Value of standard concrete



Megnesium Oxide concrete on the other hand traps CO2 while it cures, so it is considered better for the environment. It is also stronger and lighter so you can make thinner walls, but is it much more expensive and difficult to find, at least here in the USA.




Is it possible to use lime instead of regular cement?

You'll have very, very low strength. You need to use portland cement. You can and should use fly ash in your recipe (your mix design to concrete). Fly ash is a polozan - the secret of the Roman Empire. That's why a lot of their buildings are still standing hundreds of years later.
Your mix design is critical for a lot of reasons. You need strength, you want low shrinkage, you don't want your concrete to constantly be shedding dust, you don't want the surface to pop loose, and a lot of other things. Get a good mix design before you start! Pay very close attention to water cement ratio! Too much water will ruin your mix. It is best to do a lot of reading about foamed concrete before you begin. You don't want to build a nice looking structure, only to watch it crumble over time.



wondering about using Aircrete for a driveway.  making a slab 46 feet by 27 feet.

You can definitely make a strong aircrete using sand and cement mix. I made some for a test I did and it was very strong. But you would have to figure out what the best cement to send to foam mix should be.
https://www.richway.com/construction-resources/mix-designs-and-economics.html#strength

I'll start with a ratio of 90 lbs of 90 lbs of sand.



Can anyone tell me what the ratio of concrete to foam should be for a vertical insulation usage? I do not need great strength as the insulation would be encapsulated in wall cavities. The wall cavities are 16" x 96" x 3". There is fiberglass insulation in the cavities already and I suspect that it would be compressed by the AC injection and only about a 1.5" thickness of AC would be able to be injected. Please help me as soon as possible since winter is coming on!
  (minute 5)



If one were to add fibre to aircrete to add tensile strength, what sort of fibre would be best and in what concentrations? Has there been any testing to that effect?

We tested PVA fibers and it worked great. It was recommended by Steve Kornher of Flying Concrete - http://www.flyingconcrete.com/
Steve does amazing work if you haven't seen it, check it out. He's been working with concrete for decades and recommends PVA fibers. We've tried to get hemp fibers but no luck yet. We prefer to reinforce the surface with poly reinforcing fabric - https://www.apoc.com/products/roof-reinforcements-firm-polyester-reinforcing-fabric-apoc-482f
With surface reinforcement there isn't need for interior reinforcement in our applications.

What do you use the adhere the fabric to the AC?
What would you use to reinforce the subfloor for a load baring capacity of 2800 psi application?

add sand to your cement and use a little less foam and you can get the 2800 psi you're looking for. I would also add some Micro Rebar.


If you added either basalt or micro rebar your aircrete would be stronger but you wouldn't be able to use your long cutting blade to cut multiple blocks from one slab right? I would like the strength that the fibres provide but I absolutely don't want to be molding each individual block if I don't have to.




Different mixes of aircrete




A method one person uses to make test blocks on a budget:
https://drive.google.com/file/d/0B0obq8qQMi2bczE1OHNWa0gxWGs/view



as with any cement mixture, water quality affects outcome, and in this case, formation of bubbles:
We were using well water which for whatever reason was reacting with the foaming agent (seventh generation soap) and causing a reaction which collapsed the bubbles.
with reverse osmosis water the collapsing weak aircrete we had known from previous testing became an entirely different material altogether, thick, viscous, holding its shape.
Water chemistry has a lot to do with concrete! Ignoring your water chemistry when mixing any concrete is an invitation for disaster. Sulfates in your water or aggregates in any portland cement mixture are really bad. Here's a link to more information on concrete and sulfates: https://www.understanding-cement.com/sulfate.html#


an idea to create smaller bubbles:
I do know some industrial foaming folks use pure nitrogen vs air for their foam creation due it being inert and if you've ever had Guiness, you know the foam is different. (much smaller bubbles). it might be a fun experiment since i have some nitrogen tanks from brewing so I'd just need to rig up some duct tape manifold on my compressor. I really am curious about the lower limit of density. I'll try some experiments and contribute my findings.
I have a specialty mushroom farm and my mycelium blocks when totally tried out are super light and make great insulation. I think I might build some blocks with really dried out versions as the core with air crete around them thick enough to have some strength.

Eathships aren't a problem in your climate. Try looking into Francis Gendron and his "Greenhouse og the future project". He studied under Michael Reynolds, the earthship pioneer from Taos. He has customized the design for the Canadian climate. That should be more than adequate for your temperature requirements. On his website you can buy building plans for such a project and fright now they're on sale for $35. Here's the link: Greenhouse of the future
And here's a persentation video:

Kelly Hart's video and book available on Amazon detail his pumice-filled earthbag house in the mountains of Colorado, but you are a long way from any natural deposits of lava rock. Please please please don't build something that isn't adequately insulated as you will always be paying for it. I live in Northeastern Ohio. Where you are looking at is a similar climate. Earthbag is not adequate here. Straw bale or at least 15" of light clay straw or blown in cellulose are necessary. Please look up Ace Mcarleton and Jacob Deva Racusin's Natural Building Companion for more info on actually tested actually built high performance natural building for your climate.
--Uncle Mud

I've considered an earth-bag then earth-bermed house using air-crete as an insulation on the exterior of the earthbags.

Peter.  Sorry I didn't get the email reminder for this thread for some reason, and I have been away from Permies for some of that time.  

can you describe more about how you would build/layer the roof, incorporating the wool?  also, i'd love to hear more about the solarium and the trombe wall working in concert with the rocket mass heater, maybe with diagrams!  lol, asking a lot.  

 First, I should have mentioned that you must wash the wool as it will not only stink but attract moths if you don't.  I would lay the wool down between framing members of the ceiling much as one might put down fibreglass insulation, over top of the boards in the ceiling. Of course it is less uniform than batts of fibreglass, but you can heap it as deep as you like between your ceiling and your roof members, and if you have an attic space, then you have lots of space for deep wool insulation.  If I was going to put any vapor barrier, I would put it between my ceiling framing and the boards which are on the living space side of the ceiling.  

As for the trombe wall/solarium and RMH combo.  The trombe wall, in my case, will be the solarium; and will not be separate entities, just to be clear.  The solarium acts as a trombe wall since it's poleward side is thermal mass which get's struck by the sunlight from the sunward side.  The RMH can be on either side of the wall, but needs to be right up against it, so that any time the RHM is fired up, the bench, and the barrel are giving their heat into the wall as well as into the room.  A person could even have a bypass in the RMH system where a bell within the wall or a pipe system (just like as in a bench but in the wall), could be heated instead of the bench pipe system, and then the bypass could be switched back to alternate back to just heating the bench in the room.  I hope that answers your question Peter.  

Earthbag construction will give you alot of thermal storage, however like all other construction it will require an actual heat source and also insulation in a cold climate during the winter.
For insulation one could use rigid insulation or strawbale or straw-clay plaster or another layer of non-structural earthbag filled with ricehull/straw/cotton/pumice/etc   .
You would put the insulation on the exterior of the building so the temperature of the earth bag and shouldn't change much daily.
Hopefully the image below will give you an idea of an earthbag with insulated on the outside.



If you did not insulate the earthbag and had a heated inside temp of 60F and an outside temp of 0F, I would worry about the huge about of heat lots because earth bag has almost zero insulation value.

All of that said earthbag are one of the most earthquake resistant building style so I think it will be able to adjust to the temp swing even if you only used the house as a summer home and left it unheated in the winter after draining all your pipes&plumbing.

Don't forget that Mike Oehler lived in his 'earth integrated'/underground house, located in northern Idaho at zone 4, for 30 years and heated it with a wood stove. If you can take ideas from that and the wofati design, heat it with a RMH, utilize passive solar design if it applies to your site, then using thermal mass shouldn't be an issue at all.

If you can add an "umbrella" that extends out a bit for passive annual heat storage (PAHS) in the soil, then you wouldn't want insulation between you and the surrounding earth, as the earth 6-10 feet down is much more stable and helps cool in the summer and warm in the winter, relative to the outside. If you isolate yourself with insulation then you have to actively heat/cool your air instead. Temp readings on a PAHS building showed that the average temperature of the protected soil was higher than normal as a result.

The simplest way could be to do a modified timberframe for the walls and roof, then infill with earthbag. Modified timberframe just uses standard lumber built up to make posts and beams. It's pretty simple: your posts are made of two 2x8's with a 2x6 in the middle. Beams are 2x6's tucked in between. I built a house this way. Here's some examples: http://www.firstdaycottage.com/photos.html   Just space your posts every 3'. Cover your roof with plywood or tongue and groove, then moisture barrior, then insulation sheets, then strapping, then metal roof. You can make big thick walls and even add insulation. If you are near a volcanic area you can use scoria as you filling material for your bags, alternatively dirt and perlite or vermiculite.

Tom Linson wrote:Hello,

I am brand new to all this so bear with the simple questions.

My goal is to buy a tract of land and build a earth bag/berm home. I wanted to go back to Washington state but financially that may not be possible. I currently live in upstate NY and started look at NE Maine. The land is quite affordable and it's actually close enough that we could travel up there for a few days and work on the project while still living here.

My big concern is the winters. I have no doubt the earthbag home would provide us with a warm home, my concern is with the expanding and contracting of the soil during the seasons.

How to you address this?

Thanks for any help.

If you fill the bags with soil, you should use no more than about 30% clay, with the rest sandy soil, and you should not have problems with the walls expanding or contracting. They should be placed on a foundation that goes below the frost level to assure that there is no upheaval from below; a rubble trench foundation is a good choice. If the surrounding berm does not drain well, then you might want to place a curtain of sand or gravel between the moisture barrier and the berm before it is back-filled.