What Is Cob Adobe?

Cob is a building material made out of clay-rich soil, aggregate, fiber, and water that is pliable and can be constructed into walls for buildings. Many people are familiar with a similar building material called adobe, which has many similarities, but a cob house does not use bricks or blocks as the adobe method does.

What is the difference between Cobb and adobe?

The most basic difference is that adobe is formed into rectangular bricks which are dried in the sun before being used, while cob is built wet. Cob therefore lends itself to organic shapes: curved walls, arches and vaults. Building with cob is a sensory and aesthetic experience like sculpting with clay.

What is a cob project?

Cob building has many advantages, including more readily available materials, less environmental impact and decreased expenses. Building with cob involves mixing sand or clay with local subsoil and straw. This creates a stiff substance that can be molded and smashed together into small loaves (cobs).

What can you use cob for?

Cob is fireproof, while “fire cob” (cob without straw or fiber) is a refractory material (the same material, essentially, as unfired common red brick), and historically, has been used to make chimneys, fireplaces, forges and crucibles. Without fiber, however, cob loses most of its tensile strength.

Is cob rammed earth?

What is the difference between rammed earth and cob? Rammed earth is a structural wall system, which is composed of gravel, sand, and clay compacted to a stone like hardness. Cob walls are made of sand, clay and straw.

Is cob water proof?

Why doesn’t it wash away in the rain? Cob is very resistant to weathering. Because of its porous nature, it withstands long periods of rain without weakening. However, too much exposure is best avoided by the “boots and cap” strategy: wide roof eaves to protect the walls and an impervious foundation.

Is adobe stronger than concrete?

Cement mortar will accelerate the deterioration of natural (or non-stabilized) adobe bricks, however, because the cement is stronger than the adobe; foundations: The foundations of historic adobe buildings were made from a variety of materials, including seashells, bricks, tile fragments and field stones.

What is an example of cob?

A cob is a round loaf of bread. A cob is a type of short strong horse.

What is cob method?

Cob is an earth building technique based on a mixture of clay, sand, straw and water (LILI 2012). The mixture is kneaded with hands, feet or simple tools, subsequently lumps are made, that are then compressed together and shaped by hand forming foundations and walls (LILI 2012; Chiras 2002).

What is a cob system?

Chip-on-Board or “COB” refers to the mounting of a bare LED chip in direct contact with a substrate (such as silicon carbide or sapphire) to produce LED arrays. COB LEDs have a number of advantages over older LED technologies, such as Surface Mounted Device (“SMD”) LEDs or Dual In-line Package (“DIP”) LEDs.

What is cob in simple words?

cob noun [C] (CORN)
the hard cylinder-shaped part of the maize plant on which the yellow or white grain grows: Cut the corn kernels from the cob. See also. corn on the cob.

Why is it called a cob?

According to Wikipedia, the word could have originated as a variant of cop, meaning head. Cob could also have come from the English word cot for cottage, the Welsh cob for top of tuft or the German Kuebel, a large container.

How long will cob last?

How long does cob last? The oldest cob house currently standing is 10,00 years old. If this doesn’t speak to how strong and durable cob houses are, then nothing will. Cob houses are built to stand forever as long as their roofs are maintained, and they are properly looked after.

How strong is cob?

Cob has unique properties which make it as strong and more durable than concrete (see ‘How is Cob so strong’) the oldest Cob building is over 10,000 years old. Cob is resistant to fire, termites and mould.

Do you need sand for cob?

There are some rare areas where you will find soil that naturally contains the right amount of aggregate-to-clay ratio to make cob, but this is not usually the case. One of the main guidelines for choosing sand for your cob mixture is to use a rough and coarse sand that has many different particle sizes included in it.

Are cob houses efficient?

Its high thermal mass makes cob structures very energy-efficient. Its earthen components are all naturally-occurring and widespread resources, and builders can almost always source these components locally. This means a low-cost to the builder, as well as a low cost to the planet.

Is cob good for cold weather?

Cob is a suitable building material for hot or cold climates due to its ability to keep indoor temperatures stable. Depending on your comfort levels, this can eliminate the need for centralized heating systems and air conditioning. That’s some great energy saving potential right there!

Is cob a sustainable material?

Sustainable – the most sustainable form of building there is – cob has almost zero embodied energy. Since its made of earth, it his also entirely recyclable and non-polluting. Affordable – as long as you have land to build on, anyone can afford to build cob walls.

Can cob be painted?

Cob and clay are soft substances that shouldn’t be directly painted with Silicate Masonry Paint because it won’t bond correctly. However, cob or clay walls that have been coated in lime render first can be painted with the Silicate Primer and Silicate Masonry System as per our instructions here.

Do adobe houses smell?

We were shaken but undeterred. We needed another adobe builder, obviously, but we learned something else during this debacle. His unstabilized adobe bricks didn’t smell as strongly of asphalt and kerosene, but they still smelled.

Why do adobe bricks last so long?

The straw or other additional material is used to bind the brick together and to ensure an even drying process. Many modern makers of adobe bricks will add Portland cement or emulsified asphalt as a stabilizer. This makes for even stronger and more durable building material.