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jesse markowitz
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Location: Hudson Valley, NY
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Basic beginning list-

White Belt-
Help in the construction of a cob project from start to finish
Make 55 gallons of slip
Make 50 gallons of cob with a partner/partners

Make 100 gallons of cob on your own
Make a load bearing wall with cob
make and apply a plaster to a cob project
make a cob bench
Help construct a cob floor
Make an outdoor cob structure with a plaster that can withstand being rained on

Make a cob floor solo

Make a cob structure/cob and timber frame structure at least 50 square feet in size

This list is pretty light.... but all of these projects are really time consuming, so that might be okay.
Genevieve Higgs
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Sounds wonderful - maybe could "lead a cob-making team of newbies" or "teach three people about slip" or something like that be included? I've always thought one of the nicest parts of the belt system in martial arts is the culture that more advanced practitioners are encouraged to help out with the people starting out.
Erica Wisner
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Location: Okanogan Highlands, Washington
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jesse markowitz wrote:Basic beginning list-

White Belt-
Help in the construction of a cob project from start to finish
Make 55 gallons of slip
Make 50 gallons of cob with a partner/partners

Make 100 gallons of cob on your own
Make a load bearing wall with cob*
make and apply a plaster to a cob project
make a cob bench
Help construct a cob floor
Make an outdoor cob structure with a plaster that can withstand being rained on

Make a cob floor solo

Make a cob structure/cob and timber frame structure at least 50 square feet in size

This list is pretty light.... but all of these projects are really time consuming, so that might be okay.

Thanks for inviting me to comment.

Let's start by letting Ernie comment, since he actually did an apprenticeship with Cob Cottage Company.
He says the thing that's missing from that list is siting: the art of knowing where, when, and how to use cob, and when it's not the appropriate choice for a job.

The hardest part to teach is that instinct of where it goes.
I would add the development of a reliable "back of the neck" feeling when something's wrong with a project or idea, even if you don't yet have the experience to say exactly what it is.
"Stop, something's not right.... now we look and poke and prod until we know what it is, and fix it."

I think the first thing for me to say is that I don't know if I have a "bachelor degree" equivalent of cob experience yet.
I might have, oh, a minor in cob en route to a master's of rocket mass heaters, or something like that.
I can talk about some of the common problems pretty well (consistent with how well I can discuss quantum problems for a lay audience, based on some undergraduate physical science training), and I have an experienced teachers' instincts for when I'm communicating well with students and THEY are doing good work.
But given the limits of my practice (mostly indoors) there are fundamental things I don't have much experience with, and can't be sure I'm articulating correctly or be a good judge of students' work.

I also went to a weird college where we defined our own majors, and a lot of the bachelor degree was based on negotiating the value of your projects and self-designed curriculum, instead of a list of requirements and electives.
So when I try to guess what a trades' equivalent to a bachelor program is, I don't have either a "normal" bachelor degree nor a "normal" trades apprenticeship to base it on.

However, I come from a long line of people who design curriculae and training materials for a living, and have not let their relative inexperience in any particular field stop them from voicing an opinion.
Also I like to type.
Also I have a lot of respect for traditional building and have been studying it informally since I was old enough to make mud pies and doodle castle layouts, and I've been lucky enough to meet and work with experienced tradesmen and women including brickmasons, timber-framers, many of the Cob Revival builders, straw-bale and plaster artists, at least one thatcher, and a range of conventional architects, construction engineers, managers, masons, and general contractors.

So those are my qualifications for the following recommendations:

I'd make a couple of suggestions:
- I'd measure cob in cubic feet (about a 5-gallon bucket) or in cubic meters; it's easier and more relevant to measure once it's laid up in the wall.
(8" wide by 12 feet long by 4 feet tall would be... 2/3*12*4=32 cubic feet; if measuring in cm or meters it's even easier to get cubic meters).
Your initial "white belt" would represent about 10 cubic feet of cob, or about 3 large tarp-batches.
Green belt would be something like 20 cubic feet.
In any real dojo or apprenticeship, you would have made this much slip and cob in your first week, and you would make 10 or 50 times this much in your first year.

- I'm struggling with the "alone" or "solo" parts of some requirements.
I don't think making a cob floor solo is necessary unless you're going to be a contractor, and have to complete a project on deadline even though your paid labor wanders off.
Ernie says: 99% of the people out there cannot do a solo floor, either for reasons of skill, physical ability, or the unfeasable time it takes to lay a floor that way.
It is a team job, and it takes an experienced expert to lead the team (there is a LOT of leveling involved, and a lot of shoulder strength or appropriate tamping technique for your body type.)
A good floor contractor is going to bring along enough reliable help to do a floor quickly and not fiddle around with doing it solo.
We did a 2000 sf cob floor on top of an existing concrete slab, and it took a solid week of mixing cob by about 6 novices, plus a couple days of 10+ people doing the big jobs together, and a steady pace of 2 to 4 people with good shoulders taking turns laying the material, floating it firmly into place, and wheelbarrowing the material in to the guy currently floating it. You can't paint yourself into a corner at any point. After it's set, there's another week or more of finishing if it's just one person.
I would say doing a 2-square-foot floor sample that resists the expected forces (water, foot traffic, stiletto heels/chair legs, cold/heat) is good enough for a bachelors' project.
After knowing what level of work that takes, you might make an informed choice about whether to do an earthen floor, or go with something like sand, flagstone, or brick for a given part of your homestead.

Floor exercise:
Make a floor test patch sample, and test it by spilling 1 pint / half a liter of water and leave it for at least 1 hour (comparable to having dinner with small children).
Then after cleaning it up, the floor can be walked on without leaving footprints within 30 minutes later. (C grade/passing standard).
For a B, leave the spill for 2 hours before mopping up, and be able to walk on it immediately.
For an A, leave the spill for 12 hours or overnight (represents an undetected plumbing leak for example).
Document how this floor would need to be laid, including protection from ground damp, and what maintenance schedule would be expected in order to retain its strength indefinitely.

Traditional skills often involve projects bigger than one person can accomplish alone, and physical limitations may make it unwise to do certain types of activities alone (like climbing high on a wall, or lifting heavy stones).
So I'd encourage thinking of this "bachelors' of cob" as a teamwork thing, and if your team can accomplish a relevant scaled-up version of these tasks you're doing well.
Be honest with yourself if you're waiting on one particular person to get back and answer questions or check your work; you want to get to the point where you can trust your own work.

Small-scale samples are often used in the bachelor's curriculum, like helping to tend experimental plants rather than running the experiment, or doing a rough scaled-down experiment (6 or 10 plants) to get some practice with experimental design; where a statistically significant graduate research project with PhDs might involve thousands of plants. So you could make a sample or model for most of these types of projects, if you have an expert to check your work.

I'd definitely count mixing cob alone as a separate skill. Green-belt or brown-belt seems appropriate.
You don't have to do it alone most of the time, but you should not be stopped from finishing a project if you have to do a few batches alone. Or by machine.

Building at least one small load-bearing structure alone, like the model house below, seems relevant to verify that you actually have all the skills and didn't miss something important.
Note that you can work in the trades without ever becoming a project designer - but in the American cob revival, most builders do at least some of their own design work, and there is less local support to be able to hire out parts of a building and have them done properly since cob requires specific detailing.

- The idea that you can make an outdoor bench, or a plaster that can withstand being rained on - that's kind of a fallacy in some climates.
A lot of novice builders do outdoor structures without protection because they've seen pictures of other novice builders doing this. Experienced builders in some climates don't do it, because even experienced builders have a hard time maintaining some structures that are poorly designed for the local weather. Making a roof/exterior-plaster/splash footings system that is suitable for the local weather might be a better goal.

Plasters Exercise:
I might suggest a range of plaster exercises: "Make at least 3 different kinds of plasters
- one earthen plaster with natural fiber (hair, dung, or chopped straw),
- one cob-compatible finish using other materials such as lime, tadelaakt, or gypsum,
- and one other finish plaster of your choice.

Document what local materials were used, in what proportions. For at least one plaster, show test patches using different proportions of the same materials and indicate why you chose the final recipe.
Give the performance limits for your plasters (e.g. is this plaster suitable for an interior/exterior wall? What temperature or moisture ranges? How about the kitchen, stove, bathroom, shower stall, or bathtub?)."

Demonstrate that at least one of your plasters can be used as an exterior plaster in your climate. Describe the proper detailing for local weather (eave widths, exposed wall surface below eave, or drainage for parapet walls if appropriate).
If the plaster is to be used for straw-bale buildings in freezing climates, the test should include a simulation of an ice-storm followed by blizzard conditions: several hours of sideways rain followed by a freezing event, and the plaster does not spall more than 1/4 its thickness.
For cob buildings, a similar event should show not more than 1" of damp penetration (less than 1/2" for an A grade), nor spalling more than 1/2 the plaster thickness. The wall core in both cases should remain below 15% moisture levels.
Any combination of natural materials is permissible, as long as you stay within the range of materials known to provide sufficient breathability over time (e.g. no Portland cement stuccos or plastic-sheet sheathing, as they are known to trap moisture on the inside of the wall).

Describe what functions the plasters perform besides aesthetics.
-Light, sound, structural, moisture, breathability/ventilation,
-is it washable, what other paints or plasters can be applied on top of it, what surfaces can it be used on and what pre-treatment is needed, is it re-usable for repairs,
-are there other health aspects such as toxicity, alkalinity, mold resistance, biodegradability,
-and end-of-life cycle: what is the best re-use of this plaster if the wall should be removed or repaired?)

You don't have to know how to do a natural bathtub, but if you say you do, it better perform as described.

Ernie says: Much of real natural building work is testing: taking a local material, working with it until you have a reliable recipe, and then continuously recognizing the qualities of the material as you are working with it so you will spot any change in materials in time to prevent poor performance.
Moisture, texture, proportions, and mixing times may all need to be adjusted based on the weather and other factors.

The Model House:
The only solo project I'd really encourage is a sample building or model as a proof of skill, before taking on the responsibility (and liability) of designing things for people.
I think the beginner/bachelor version of this goal might be:

- Build a scale model of a cob house that is at least 1' in diameter, using available local materials, and leave it outdoors for 2 years while observing its success or failure in local weather conditions.
Repairs and maintenance are encouraged, as long as they are documented. Keep a log or journal for observations, including custodial experiments.
It is perfectly permissible to deliberately over-stress your model, for example by hosing it down or sitting on it, and then re-build using the new information gathered by this destruction testing.

After the first successful year your model remains intact, resisting all weather, you are nominally qualified to build a storage barn.
Consider re-building your model as a coop or hutch for birds or small-animal husbandry; or as a drying-rack for harvest processing.

Continue to "play house" with your model in the following years.
Use it to test out new skills like plumbing (miniature sink/bath), heating (candle or lamp), durable finishes (floor for the rabbit hutch), etc.
Run scenarios for a week or more in each season, operating the utilities and observing any effects such as
- wear or cracking on finishes,
- patchy dampness or dryness,
- condensation, mold, etc.
(It may be particularly satisfying to use the actual energies while modeling a fictional home, for example locating the model so its candle serves as an outdoor path light; or hooking the water tap so your pet can use it as a drinking fountain.)
- If children are available to play with the model and imagine the occupants' daily lives and concerns, encourage them, and listen in.
Observe effects. Experiment with ways to mitigate any problems you discover.

As you approach your black belt/senior year equivalent, examine the model to see if it still represents your best work. If not, remodel or rebuild it so that it does.

Field trips
are essential for builders to learn from previous work in the climate. In order for a culture to remain stable (or "permanent"), there must be enough learning to keep up with the rate of lost knowledge when elders die. And there must be enough iterative improvement to adapt the successful methods to gradual changes in climate and other conditions. Untrained novices re-inventing the wheel, or building 'unique' creations that don't fit local conditions or traditions, are wasting efforts that might be better applied to working together and moving forward from the best available knowledge and practices.
A good designer is going to base 95% of his project on proven, time-tested local traditions, arrange them as gracefully as possible, and with that last 5% of innovation the designer makes some signature improvement.
A very good and humble designer makes that improvement easy to replace if it doesn't work out. Knowing how to do these things takes a great deal of practice and familiarity with local building methods and traditions.
A self-indulgent designer is going to make something that is 95% untested, and therefore 75% non-functional, and use the 5% connection to reality to give it a pretentious name such as "House/Inverted." Whether re-introducing primitive materials, or working with ultra-modern new materials, it's easy to get the design wrong if you've never lived in anything like it.
Building iteratively, a chicken coop then a barn then a cottage then a manor, is the most reliable way to get good value from effort without over-reaching. Visits and occupant interviews are the next best thing.

- Visit older cob buildings in your climate, and the oldest surviving traditional buildings of any type. Historic and archaological sites may offer insights into pre-industrial and pre-historic methods.
If your goal is to build with cob, consider other masonry buildings like limestone, fieldstone, adobe, sod, or brick; or hybrid buildings with some earthen components like timber-frame with plastered infill panels. Looking at civil engineering (dams, berms, earth-sheltered buildings and retaining terraces) may also be interesting.
While visiting,
- Look closely at details like foundations and footings, roof eaves, drainage, and material selection and combinations.
- Ask about hidden details like damp-proofing, foundation depth, interior core materials, and where the materials were obtained.
- Ask what maintenance or upgrades they've done, and whether they would do anything differently.
- Visit similar buildings in climates more extreme than yours (wetter, colder, more extreme storms, temperature swings, earthquakes), where you would expect problems to be revealed sooner.

- How are roofs traditionally constructed, drained, and maintained? How are vents, chimneys, or additions fitted through/around the roof?
- What is the worst regional weather, and how does it affect the structures and detailing? (snow loads, wind, wild-fire, seasonal storms, flooding may affect site choice as well as building design)
- What local materials are used most? What local materials seem to last the longest? Are there any building parts that are made exclusively with imported materials, such as roof or hinges?
- What are the points that fail first, or require the most careful detailing or frequent repair? (e.g. ends of timbers, frost heave, acid erosion, plumbing or flooding damage, cultural changes in use or regulation)?
How are these problems repaired while conserving most of the building?
What repair methods or upgrades most frequently cause new problems?

- Ask around about older buildings that have failed, and find out why.
- Look for differences in materials, construction, siting, etc. between abandoned buildings and those still in service.
How much is due to design and construction detailing? Urban planning or outside infrastructure decisions? Luck?
- Are there cultural factors that explain an otherwise-puzzling shift in building styles, such as land rights, warfare and weapons, trade relations, population migration, climate changes, or political or fashion influences from outside the region?
Are there building materials or styles that seem to resist cultural changes?

Benefiting from Others' Experience:

- White belt: Visit at least 3 masonry buildings, and find some details that wouldn't show on a postcard.
Take at least 1 class, workshop, or go volunteer on a project being led by a master practitioner who has at least 10 years' experience in the field.

- Green belt: Visit at least 3 earthen masonry buildings more than 10 years old, within a day's drive;
examine the roof, drainage, site, and repairs as above, and compare the condition of original (unrestored) and repaired sections.
Put in at least 3 days in formal classes, or 10 days on volunteer projects, working in a similar climate under a master builder (10+yrs).

- Brown belt: Visit at least 3 masonry buildings more than 100 years old, or the oldest available in your region/climate.
Examine as above, with particular attention to human factors like changes in use/regulation. Research how pre-industrial buildings were built by older cultures in this or similar climates.
Participate in a multi-day building project/event in your region. Observe all of the following, and do at least 3 of them: foundation, structural, door/window, utility (plumbing/electrical/heat), roof/weather protection, floor, and finish work.

- Black belt: Build a demonstration project with some practical purpose other than human habitation, to demonstrate your knowledge of the entire building process (all the areas above).
You may design the project or use a traditional design.
Consider a small barn/storage shed, outdoor kitchen, guest cottage/studio, or similar outbuilding of up to 100 square feet/10 square meters.
A team of 6 trained apprentices can generally build such a project in something between 2 to 12 weeks.
If you are working solo, consider scaling down your project to allow completion within one season.

Ernie: The biggest thing is to build something that's going to be used. You see a lot of "demonstration projects" that are never used by anybody for anything. If it's not used, you don't learn anything about how it stands up to ordinary use - you want the plasters to get bumped, the door to swing into the wall, all those ordinary moments that can cause damage and wear.
So think about a small project like a cob oven with a roof, or a smoker, or a doghouse, or something.
That kind of project will teach you more than a "studio" in someone else's backyard if you're never going to see it again.

Next Steps (Teacher Cred?)
Before attempting to teach without supervision, follow up on all the projects used to qualify so far.
(At least 3 standing projects where you were substantially involved, out of a total of at least 10 different projects including prototypes, failed projects, and projects where you learned something even if only briefly involved.)

- Get a detailed performance report from the current owners/users.
- Take 1-year or 3-year photos showing successful finishes, and details of any problems or remodeled details.
Ernie: Failure tells you as much as success - document the really big failures carefully if you want to serve as a good teacher.
- Erica: Develop a list of the most critical errors that are commonly seen in your region and how to prevent or remedy them.
Present this list to your expert instructors, and ask them to check your work.
(If all 3 of your expert-supervised projects were under the same person, consider approaching a second expert for supplemental training at this point.)
If possible, serve as an assistant instructor for several workshops under different experts before teaching solo.

A good indicator that you are becoming a skilled tradesperson is that people you respect start offering you work, and especially offering wages, gas money, or other incentives for you to join a project or workshop.
If none of your instructors have delegated chore supervision to you in any workshop you've taken, that may be an indicator that you're not yet ready to teach. Offer to serve this role and see what response you get.
Ernie: Don't be insulted by being told you're not ready to teach yet. It takes time to develop these skills - both the cob, and the teaching.
Erica: Traditional trades apprenticeships run 4 to 7 years. The shorter programs usually build on already-in-place skills - much as a bachelors' program assumes you can already read and write. 3 years might allow a skilled brickmason to become a masonry heater builder, for example. Trades experience doesn't relate very closely to the current school curriculum in most places, so people who are used to moving from one job to another using their reading-writing-and-arithmetic skills may have a hard time starting back down at kindergarten-level when it comes to safe tool use, situation awareness, or structural standards.
Many people can be a 'chore boss' at a basic level; chores like mixing slip can be taught in a few minutes, and it's easy to fix if the consistency isn't right. All you need for that is a person responsible enough to keep doing it, and social enough to recruit help when needed.
Sometimes being a chore boss for a more complicated chore is more about personal responsibility and self-knowledge than about prior experience. In a workshop of 20 or 30 people, I might ask one or two to take over as a task bosses for prep chores like mixing materials, and leave them largely unsupervised, trusting their self-knowledge to know when to come check something with me.

The other thing to consider is that there's no substitute for years of practice, for generations of cultural experience, nor for direct observation.
Gifted masters in the skilled trades are often better working with the materials than teaching. It's important to recognize these are two separate skills. Even in pure academics, a good researcher or writer and a good teacher may not be the same person.
Some experts in a physical skill may struggle with a fear of public speaking, or get upset and defensive if apprentices ask too many questions, or have a specialized vocabulary that they have known so long that they literally can't translate it for those unfamiliar with the terms.
The only way they can teach with confidence is to get a LOT of practice so they are not thrown off their game by having a greenhorn along.
Some master crafters never become teachers. Some become poor or abusive teachers who can only share their excellent expertise with a limited subset of students, based on compatible personalities or tolerance. Some become exemplary teachers, or are able to write books or produce videos that help thousands of people train in their field. And some few have their skills captured despite their disinterest in training others, becoming guest experts in someone else's how-to series, or being misquoted by passing anthropologists and news reporters.

So what do you do if you are one of those people who learns best by teaching?
You don't want to teach others "wrong," but you also know that the process of explaining and demonstrating helps you learn much faster.
You are not interested or able to work alone all the time, and you love the rush of working on a big project with lots of people.

I'd suggest hooking up with an expert whose skills you respect, who either has too many students and wants help running larger classes, or who is willing to come in at a couple of points during your student-taught projects and give some pointers.
It is of course also possible to invite your friends over for pizza and try something together - and there's nothing wrong with friendly work-parties without an expert leader, just everybody doing the best they can and playing nice together.
Unless you have a real problem with authority, however, I think generally finding someone more experienced than yourself to lead or advise on a project helps a lot when learning new skills.

- Genevieve - I like the idea of advanced students working with novices, and I agree that martial arts does this well.
However, there are two things they do very well and very differently from permaculture:
1) There are specific rules that have been iteratively developed over time to allow teaching these dangerous skills without harm. Permaculture is not seen as intrinsically dangerous, so we often just leap into practicing together. It may be some time before permaculture is old enough to recognize the patterns of harm that sometimes result, and to curb that practice into reputable and disreputable methods.
2) There is an authority structure, with clear distinctions between novices and experts, and in reputable dojos all courses are led by an expert.

Permaculture is very egalitarian, by intention. Mollison's format grants people "designer" status after 2 weeks' conceptual training (PDC), with little if any hands-on experience. These PDC graduates are not experts. They are empowered novices.

You wouldn't show up two weeks into the college term and confuse a freshman student with the professor; in some cases they won't even know where the nearest bathroom is, yet.
In cob building, we have a lot of people who say their summer internship turns them into a qualified professional, and courses that are sold as "complete cob" for the owner-builder.
You can certainly build something after these courses - many people have - and you almost certainly shouldn't bill yourself as a "cob expert" yet. Many people have come to grief on their first project, or even though they love it, they wish they had known certain things before they built it. The fact that people do teach even while working on their first project is at best a generous impulse to share, and worst a form of predatory pyramid-scheme or Huck Finn scam. Cob is more fun with a group. But do please be clear with your group what your actual experience level is, and give experts the respect they're due.

In the aikido school I briefly trained in, I think the general standard was to reach your 3rd dan black belt before you would be allowed to teach scheduled classes.
Junior members with good teaching or kids' skills might assist in a class before this point, and any student might be invited to come lead the warm-up exercises or be part of the instructors' demonstration. Advanced students (brown belts, for example) are always encouraged to attend classes with novices, and to be helpful in practice, but they are learning together under the supervision of a qualified teacher.

Above the black-belt level in this school of aikido, it took about a year of bi-weekly practice to build up enough hours to advance; if you practiced every day you could advance as often as there was an examination test, about every 4 to 6 months. So the qualified teachers were generally at least 2 to 3 years of active practice beyond their black belt. They would be certified not by their immediate teacher, but by a higher-ranked master brought in for the belt exams.
Many of the junior teachers would go beyond this minimum - they'd go to study in Japan, or train under the higher-ranked teachers at conferences or in other schools, before they might want to teach in their home dojo. There were occasionally exceptions where a 2nd-dan black belt might get permission to teach because there were no local teachers for a small town, but they would bring their serious students to the conferences or the bigger dojo for examination and more advanced practice. Generally, new teachers worked extensively with the head of the dojo, and other senior students, as they learned to safely teach what they'd practiced so far.

This was in New Zealand, in a school with three local dojos and 3 or 4 senior teachers as well as half-a-dozen junior ones; by contrast, I've seen American dojos with only 1 or 2 qualified teachers because advanced students tend to start their own school as soon as they qualify to be a junior teacher. If the qualified teacher moves away, sometimes you have a headless little school of junior students practicing together, despite there being qualified instructors less than 30 minutes away. Americans seem to value convenience and personal style, over contributing to a larger tradition. We can be self-promoting to a fault.

I've seen a lot of cob benches in Portland, built by novices being trained by other novices whose entire previous experience was helping build a similar cob bench, which tend to melt in the rain after a few years. A rotating crop of 2- to 4-year college students, and dilettante festival-goers with genuine interest and enthusiasm but almost no practical experience, helps create a steady supply of poorly-conceived projects to replace those that are falling into disrepair. The youthful creative energy of the town goes into change (designing/building/remodeling/demolishing) rather than maintenance.

As a novice, I had the privilege of attending a gathering of experienced builders in the Portland, OR city repair Project offices. I took notes on their discussion of about a dozen different waterproofing methods that had been tried (I remember wax, oil, thinned or heated mixtures, waterglass, stone/tile, silicone caulk drip-lines, burnishing, specialty plasters such as lime or tadelaakt, sculptural detailing for drainage and ventilation, and the pro and con of incorporating other materials such as wood and metal). As I recall, those builders as a group concluded that building exposed outdoor cob benches in Portland's constantly-damp climate was just a poor design choice. They had all attempted it or been part of projects like that, and all had seen it fail numerous times. A roof and a good foundation above the ground damp were the essentials to a professional-quality project for that climate; projects located under deep roof overhangs outlasted the others by double or triple the years, and were much more satisfying to use and maintain. One builder suggested a bench that was basically a curved wall with a removable seat: the wall would have its own tile roof, and the seat would be a plank, with any water on the walls able to freely run down and drain away without being trapped in the bench seat area.

Working on a cob bench with a roof, under the supervision of an experienced builder, novices and half-trained interns could interact with a great deal more positive progress in skill level compared with the novices-teaching-novices mud fest approach. It's the difference between joining a dojo (or even just attending the occasional class with qualified teachers for self-defense), compared with playground wrestling where that one kid keeps saying, "Grab my wrist!"

I'm not sure whether the PEP model is supposed to represent a "major" in the area being studied, or just a bachelor-level course such as Lit 101 for that area.
There are of course dozens of possible 100-level cob courses, different projects or types of skills you might want to try first, and you wouldn't need to do every single one of them to have a major.

If it was some kind of Permaculture University with all kinds of courses available,

A minor in cob might include
- Natural Building 151: Examine buildings using minimally-processed materials for the local environment, and sophisticated designs from various climates worldwide.
- four courses in one's chosen specialty (structures, finishes, or a specific style of detail such arches and lintels),
and at least one course each in
- foundations,
- structural work,
- roofing and drainages,
- finishing. (see "Plaster Exercise")

A major in cob should include the above plus
- Four to ten expert-supervised project experiences, including all phases of the building process
(siting, drainage, design, foundations, structural, roofs, floors, suspended floors, finishing, remodeling and repairs, maintenance)
- Climate and historic context 325: field trips and research to get familiar with "do and don't" detailing methods for your climate, contrast with other climates' methods, knowing how to use local materials for the chosen solutions, and be able to correctly demonstrate a dozen methods for repairing the 6 most common critical errors for your climate.
- Designing with Cob 121: Foundations, roof extension, thermal performance and use in interior passive solar design, and self-supporting wall construction including lintel, arch, span, using curves and corners, and understanding shear, tensile, and compressive strength.
- Designing with Cob 215: Estimating structural loading and soundness (height, seismic, frost, wind), passive solar performance, weather resistance, local materials and design limits, and compatible materials for high performance (water proofing/resistance, insulation, reinforcement). Includes a critique of one excellent traditional structure, and one student-designed structure, with attention to structural performance, thermal performance, fire and flood safety, intended use, and both initial and maintenance costs in terms of funds and embodied energy, time and materials.
- Cob materials 350: Demonstrated ability to source, grade, batch-test, and evaluate the performance of local materials, using affordable on-site methods. Make test bricks and compare their performance. Use provided test bricks and client report to create an improved recipe, using no more than 1 off-site ingredient. Articulate the conditions under which you would recommend against cob for a stated site and goals.

- Final project: Demonstrate the ability to design and build a safe structure, or evaluate and restore one from unsafe condition to safe and functional.

The "bachelor level" course is still a long way from mastery, as an engineering student is still a long way from being a licensed engineer, let alone an experienced one.
The trades are somewhere between the level of intense situational awareness needed to wrestle with the raw environment (like seafaring, firefighting, or making a living as a forager), and the systematized knowledge of an academic researcher or trained and certified professional. A tradesman knows his local materials, the geology and weather as it affects his craft, the history and politics of what's happened in the past, and keeps up to some extent on new tools, materials, and methods that are becoming available from other regions. He knows what the codes say, what the old codes allowed, which counties had lax or incompetent inspectors, and what the locals tend to do when the inspector isn't around. Knowing how to read a blueprint, and knowing what to actually expect behind a wall, are two very different skills, and the tradesman needs both. You can teach ideas much faster than you can teach experience.

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