Vernacular Native Building in Missouri

So, I've been wondering about the best sustainable home type one could build in Missouri.

Missouri has the challenge of having Winters where snow is a frequent occurrence, but is almost sub-tropical in Summer.

I decided to check the vernacular construction of the Native Americans from the area, and found that the Mississippian culture (which thrived for nearly 1000 years), as well as used by Native Americans throughout the Upper Midwest (in even colder climates like Nebraska, Minnesota, and the Dakotas).

I was aware that the Pawnee (who lived in Eastern Nebraska, which is where I now live) made earth lodges, but I was unaware that this was used by the Mississippians, as well.

http://en.wikipedia.org/wiki/Earth_lodge

The fact that this building style spans several climate zones is a good indicator that its design uses the earth as a good temperature moderator. My largest concern with building in Central Missouri was summertime humidity regulation.

I'd like this thread to serve as a sounding board for updating this design concept to more modern principles, improving on it, but keeping the same strengths that this vernacular construction brings to the table.

Strengths:

-- Earth sheltered/partial below-grade for temperature moderation.
-- Living roof. They used willow wattle, covered with thatch (insulation) and then clay (water-shedding) and then soil.
-- Airlock entry. Entry vestibule creates both privacy and windbreak.
-- Round design around a fire-pit provided even heating. Larger lodges were oblong, with multiple fire-pits. Smoke-holes were covered with bullboat hides during inclement weather (water-proof).

If you were to improve on this architecture to make it even more comfortable/habitable by today's standards, what would you do? How would you improve on humidity regulation (preferably as passive as possible)?

Assume that we replace the open fire pit with a masonry stove with chimney.

Thanks in advance!
Kevin

Looks kind of like a Wofati

NOT sealing it airtight is part of why they didn't have the mold problems of modern houses, although they probably still had condensation.

I am betting they were packed in fairly tight for sleeping, camping tent tight. You would need lots of ventilation and very little additional heat even in the winter if that was true.


My modern improvements:

Rocket stove with mass bed. That will keep you warm when you sleep no matter the temps of the house.
Solar chimney with damper. Passive ventilation enhancement.
Whitewash lime interior. Both for light and mold control.
PAHS/Wofati umbrella to keep the envelope dry from the big Missouri rains. But have a way to let any moisture OUT, maybe a cupola or gazebo over the solar chimney area so it is easier to breathe the interior.

R Scott wrote:
Solar chimney with damper. Passive ventilation enhancement.

Solar chimneys would only work in the daytime when the sun was shining on the pipe. I'm wondering if a wind catcher would be a better option?

Jennifer Wadsworth wrote:

R Scott wrote:
Solar chimney with damper. Passive ventilation enhancement.

Solar chimneys would only work in the daytime when the sun was shining on the pipe. I'm wondering if a wind catcher would be a better option?

Good point. Probably should have both, as we have hot still days and hot cloudy days but not so many hot still cloudy days or nights.

Yeah - "both" seems like a great option.

When I drive around rural northwest Missouri, I see a lot of earthberm houses, exposed only on the south-facing side. Some have green roofs, some have traditional roofs, but because of what I assume is their traditional construction and HVAC systems in the structure itself, venting out the roof appears to be with traditional methods for both HVAC and waste water. I'd like to see some real data on the total real costs of building one of these compared with the actual savings in living in one of these in a traditional (non-permie) lifestyle.

I think the earth lodge idea would be great for livestock, too.

Those earth-bermed houses were much cheaper to build in the 80's and 90's but not anymore with current concrete prices.

They do well on cooling in this climate (usually there was no insulation) and heating saved from the sealed nature vs. pre-tyvek stick homes (plus lack of window). I don't think there is much difference between them and a good AIRTIGHT home built today.

Thanks for your replies, everyone!

The solar chimney is a good idea. What if we were to combine it into a solar chimney/trombe wall? Insulate the interior side of the trombe wall, which has a large thermal mass. Then it will continue to generate an updraft in the chimney until late at night.

The trombe wall can vent out, creating a draft in the Summertime from a subterranean intake, or alternately vent back into the home interior in the Winter as heating.


One thing I'm concerned about with putting a rain shield over the roof, is that it holds moisture in. Since the walls will be underground, we don't just make this home air-tight, but also vapor sealed. We'd then need to do some kind of air exchange for humidity control.

The original native earth lodge would have drawn moisture out through the roof, the grasses on the living roof drawing moisture up and transpiring them out. The clay layer would have shed water fairly well during a rain event, especially with some kaolin content... the clay swelling to seal up once it reached a certain saturation point.

Dan Grubbs wrote:When I drive around rural northwest Missouri, I see a lot of earthberm houses, exposed only on the south-facing side. Some have green roofs, some have traditional roofs, but because of what I assume is their traditional construction and HVAC systems in the structure itself, venting out the roof appears to be with traditional methods for both HVAC and waste water. I'd like to see some real data on the total real costs of building one of these compared with the actual savings in living in one of these in a traditional (non-permie) lifestyle.

I think the earth lodge idea would be great for livestock, too.

I just saw one of these in Fullerton, NE last weekend. Traditional asphalt roofing. I'm sure they save on energy bills, though, from the earth berming. Plus a lot safer in a tornado!

The livestock idea is good. Also would be a good tornado-resistant barn.

R Scott wrote:Those earth-bermed houses were much cheaper to build in the 80's and 90's but not anymore with current concrete prices.

They do well on cooling in this climate (usually there was no insulation) and heating saved from the sealed nature vs. pre-tyvek stick homes (plus lack of window). I don't think there is much difference between them and a good AIRTIGHT home built today.

No need for concrete. I am imagining an earth lodge using log poles as the main support, or perhaps posts of earthship style rammed earth tires. Then, some earthbag in-fill between those posts-- which can be insulating, if filled with the right material.

I would wrap all below-grade walls and floor in a moisture barrier.

Kevin, I have been reviewing this very subject over the past few weeks. I think an earth lodge, hogan or kiva (sans religious accoutrements, but that still might not satisfy some) would be a good candidate for the wofati treatment. Timber might last longer if you don't plant them in the ground (check out this permies thread, particularly this post by Jay White Cloud) -- or just plan on rebuilding every 10 to 15 years, like the native inhabitants did.

The thing many people don't remember is that these structures were often only used seasonally. It was not uncommon for there to be a summer home and a winter home built fairly close together.

I was just reading my copy of Native American Architecture to refresh my memory on the topic of town (round) houses and earth lodges. There are many structural similarities between those, as well as the larger grass houses. It also states that early mound builders built something similar to earth lodges, but later switched to wattle and daub walls and thatched roofs. (I think it may have been an adaptation as temperatures began rising after the Little Ice Age negated the need for the heavier construction in more southern latitudes and lower elevations. It may even be that it was a return to previous styles that had been "temporarily" (a few hundred years) adapted to the cooler conditions.)

I don't know how well an earth lodge would survive a powerful tornado. I don't think it would be as simple as just throwing a few inches of dirt on the roof, especially for such a large interior space (compared to a tornado shelter).

If you want something that you can get a mortgage, insurance, equity, low utility bills, and be tornado resistant (I would never say "proof" as nature can be surprising) you might want to look at a monolithic dome (thinshell concrete), above or below ground, or some type of sacrificial foam form system (of which there are many).

I would rather avoid Portland cement, due to embodied energy. I am willing to use a limited amount of hydraulic lime for stabilization or plasters.

I am less concerned about a mortgage on a building. I would prefer to mortgage the land only, and build with free/on-site and low-cost materials.

I am thinking of a round earth-lodge type house, but much more earth-bermed than the original concept, perhaps buried up to 6-8 feet deep, so that the roof's eaves would pretty much come down to ground level, except on one side, which would have a "cut out" for a single exposed wall.

If we replaced the log posts with rammed-earth tire columns instead (ala earthships), we'd not have to worry about rot/decay, and we could also fill out the wall space between the posts with non-structural material. I wonder how well a light-straw-clay, with some borax added, might hold up as wall in-fill below grade, acting as a moderate insulator and humidity moderator (I would vapor wrap the walls against the earth, so the clay in the walls would help with interior humidity). A moisture-protected earthen floor is also in my mind as a good idea.

Tornado resistance is just an added bonus. A round home with a low above-ground profile will be more tornado-resistant (and resistant to straight-line storm winds) naturally, presenting less for the winds to grab onto. A heavy roof with log poles, anchored to rammed-earth tire columns, and covered with the weight of earth will reduce the chance of the roof lifting off. Any occupants will be below grade already, about as safe as anyone can be. If there's one wall that is exposed with glazing, occupants can choose a cover location away from that one wall. Should provide plenty of protection from F1-2 tornados, at the very least.

I've been re-thinking this a little bit.

So much of the problem with below-grade building is dealing with moist soil against the walls. The insulation and moisture barriers needed put serious constraints on the kinds of support walls needed. If we went with a PAHS style umbrella out from the walls and beneath, we could use the Oehler PSP system without fear of rot (as the wood will always stay dry). Furthermore, I could imagine roof poles of round-wood bolts being buried beneath the umbrella (also remaining dry), with the dry soil above it also acting as ballast to support the roof. There would be no need of a bond-beam, since the poles would be sunk deeply into the dry soil, and would not spread. I'll see if I can throw together an image of what I have in mind.

google xeni winter earth lodge. the third picture looks like it could match your ideas

Jonathan Overlin wrote:google xeni winter earth lodge. the third picture looks like it could match your ideas

Yeah, that's pretty good! I wish there was more info on it!

What about hemp crete. For sub walls breathable less rot.