“No house can be conceived more warm and cosy than that built of cob, especially when thatched.”
— A Book of The West, Sabine Baring-Gould, 1899
“Cob walls for garden fruit are incomparable. They retain the warmth of the sun and give it out through the night, and when protected on top by slates, tiles, or thatch, will last for centuries.” — A Book of The West, Sabine Baring-Gould, 1899
“Walls of mud, or of compressed earth, are still more economical than those of timber, and if they were raised on brick or stone foundations...their durability would be equal to that of marble, if properly constructed and kept perfectly dry.” — An Old Authority, 1833
You can find suitable soil for cob almost anywhere on Earth, except in places where you have chalk almost at the surface (either soft or hard), as in parts of the U.S., Germany, France, Denmark, The Netherlands, Syria, Egypt, and of course, England: the chalk country above all!
When life gives you chalk: build with "chalk cob". Just exchange soil for soft chalk reasonably crushed, and make sure it does not get wet, because it is possibly the most water sensitive of all building material, but well built it will give you exceptionally strong walls.
If you have hard chalk on your land you can cut it into bricks and use as is (not water sensitive). Exceptionally good. If you live near a chalk quarry you can build an entire house in these, at a fraction of the cost of concrete or fired clay bricks.
Chalk was (and is still!) commonly used for flooring of cow sheds and stables: it absorbs the animal urine, keeping the floor and bedding drier, healthier. Very hygienic. It also costs almost nothing compared to a concrete floor and it is carbon neutral, unlike concrete.
Our ancestors used chalk to make acidic soil neutral and better for agriculture. We still do this today. As a bonus, the chalk mines would make for excellent wells, underground cisterns, cellars. Many of these still remain in England where they are called "deneholes".
"But what about cob in wet climates?" In the old days builders would start with stitching together a thatch coat or covering that would eminently protect the unfinished cob walls from rain for weeks if necessary. Like the thatched roofs of hay ricks. There were even machines.
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Gus Willard Van Beek (1920-2012, Dept. Anthropology, National Museum of Natural History, Smithsonian Institution) on the thermal properties of traditional earth and mud homes, citing a 1970s experiment in Iran. Stellar result from the "free dug at site material".
A preliminary understanding of how soil and earth works as a building material can be easily tested digging a hole and measuring the temperature therein. (Photo of the authors at a site in Egypt.)
In the late 1950s James Marston Fitch and Daniel P. Branch measured temperatures in traditional adobe homes in the U.S. Southwest. You really do not need air conditioning in a house built like this: the interior temperature is stable. (Example of a traditional home to the right.)
#3: All this street vegetation and the many trees will require a lot of water. To help, make all buildings water independent by encouraging rainwater harvesting. The goal should be to cover 100% of domestic use.
At its time the Indus Valley Civilization city of Dholavira, founded in 3000 B.C. might have been the most technically advanced city in the entire world. Here as it might have looked around 2100 B.C. With a population of 15,000-20,000 at 0.6km² a density similar to Manhattan.
Located on the island of Khadir in the great salt desert of the Kutch, just on the edge of the monsoon region, meaning that its ground water was salty or brackish, and the monsoon rains often failed: it could go several years without a drop of rain. But the city had ample water!
One third of the city was devoted to water management: huge reservoirs cut deep into the rock was used to store fresh water from two rivers that only came to life during monsoons. These reservoirs linked to wells, silting tanks, etc. offering better water than many modern cities.
Why did Khmer and Mesoamerican cities collapse between 900-1500 while more rural surroundings survived unharmed? The common theme seems to be a long term investment in soil and water management resources. Meanwhile, us moderns are doing nothing of this. sydney.edu.au/news-opinion/n…
The ancient cities that survived for more than half a millennia all had two things in common: they took relatively good care of their surrounding forests and soils and they did not hesitate to pour any amount of resources, land, effort, labor into securing good and healthy water.
The (by now) legendary S:t Eriks neighborhood in Stockholm. Built 1995-1998 on 0.06km² with 770 apartments, parks, public places, giving it a population density far higher than modern Manhattan. The whole area was uniformly built in the hugely popular 1920s "Swedish Grace" style.
The area used to be the site of a large hospital, and some buildings were kept, some moved, like the handsome chapel building of the former hospital which now serves as a neighborhood church.
Most buildings follow the successful 5-7 stories of human scaled urbanism but there's two towers that form a portal leading into the neighborhood from a charming park area by the "Orphanage Bay" (named after the orphanage of the old hospital).
Foraging trip today. Great work for children. Here's five minutes of Juglans ailantifolia, Japanese Walnut (lit. demon walnut, onigurumi, on account of its devilishly hard shell). In most of them the husk had completely rotted away saving us much labor.
Another bonus of waiting until the husk has rotted away is that you let squirrels have the first pick (they tens to go for the smaller ones you don't want anyway with a thinner shell). Here are empty walnut shells discarded underneath a tree with a squirrel nest. Squirrel tracks!
Here's a large stand of egoma (Perilla frutescens, or Korean perilla). The leaves are great in salads, as garnish or as tempura or in sauces. A couple of weeks more and they'll be seeding: makes for good lamp oil! All indoor lighting in Japan used to be egoma oil until 19th c.