Term: Mudbrick

From Wikipedia, the free encyclopedia

A Mudbrick is an unfired brick made of clay.
In warm regions with little timber available to fuel a kiln, bricks were generally sun dried. This had the result that their useful lifespan is reduced to around thirty years. Once a building collapsed, new bricks would have to be made and the new structure rebuilt on top of the rubble of the decayed old brick. This phenomenon is the primary factor behind the mounds or tells on which many ancient cities stand.
The earliest use of mudbricks was in the Near East during the Pre-pottery Neolithic B period. The Sumerians used bricks that were flat on the bottom and curved on the top, called plano-convex mudbricks. Some bricks were formed in a square mould and rounded so that the middle was thicker than the ends.
Adobe is a common substitute for the word mudbrick.

Term: Adobe

From Wikipedia, the free encyclopedia

Adobe is a building material composed of water, sandy clay and straw or other organic materials, which is shaped into bricks using wooden frames and dried in the sun. It is similar to cob and mudbrick. Adobe structures are extremely durable and account for the oldest extant buildings on the planet. Adobe buildings also offer significant advantages in hot, dry climates, as they remain cooler as it stores and releases heat very slowly.
The word "adobe" is Spanish and comes from the Arabic "at-tub", the brick, and from the Coptic "tObe". The word may be pronounced ah-doh-beh or uh-doh-bee. Buildings made of sun-dried earth are common in the Middle East, North Africa, and in Spain (usually in the Mudejar style). The method of brickmaking was imported to the Americas in the 16th century by Spaniards.
A distinction is sometimes made between the smaller adobes, which are about the size of ordinary baked bricks, and the larger adobines, some of which are as much as from one to two yards long.
In more modern usage, the term "adobe" has come to mean a style of architecture that is popular in the desert climates of North America, especially in New Mexico. (Compare with stucco).

Composition of adobe
An adobe brick is made of soil mixed with water and an organic material such as straw or animal dung. The soil composition typically contains clay and sand. Straw is useful in binding the brick together and allowing the brick to dry evenly. Dung offers the same advantage and is also added to repel insects.

Adobe bricks
Bricks are made in an open frame, 25 cm (10 inches) by 36 cm (14 inches) is a reasonable size, but any convenient size is acceptable. The mixture is molded by the frame and removed. After drying a few hours, the bricks are turned on edge to finish drying. Slow drying (shaded) avoids cracking.
The same mixture to make bricks is used for mortar as well as for plaster on interior and exterior walls. Some ancient cultures used concrete for the plaster to protect against rain damage.
The largest structure ever made from adobe (bricks), was the Bam Citadel, which suffered serious damage (up to 80%) by an earthquake on December 26, 2003. Other large adobe structures are the Huaca del Sol in Peru, built using 100 million signed bricks, and the ciudellas of Chan Chan, also in Peru.

Thermal properties
An adobe wall can serve as a significant heat reservoir. A south facing (in the Northern Hemisphere) adobe wall may be left uninsulated to moderate heating and cooling. Ideally, it should be thick enough to remain cool on the inside during the heat of the day but thin enough to transfer heat through the wall during the evening. The exterior of such a wall can be covered with glass to increase heat collection. In a passive solar home, such a wall is called a Trombe wall. Adobe has a relatively dense thermal mass, therefore this type of construction is most useful in tropical climates. In temperate climates it is less effective to heat a structure this way due to heat leaching by the ground and walls.

Term: Rammed Earth

From Wikipedia, the free encyclopedia

Rammed earth construction, also known as pisé de terre or simply pisé, is an old building method that has seen a revival in recent years as people seek low-impact building materials and natural building methods. Traditionally, rammed earth buildings are common in arid regions where wood is in scarce supply.
Walls are constructed from a mixture of earth that has suitable proportions of sand, gravel and clay sometimes with an added stabilizer. Traditional stabilizers such as lime or animal blood were used to stabilise the material, but cement has been the stabilizer of choice for modern times.
Formwork is set up creating the desired shape of the section of wall, damp material is poured in to a depth of between 100 to 250mm (4 to 10 inches). A pneumatically powered backfill tamper - something like a pogo stick with a flat plate on the bottom - is then used to compact the material to around 50% of its original height. Further layers of material are added and the process is repeated until the wall has reached the desired height. The forms can be removed immediately, this is necessary if wire brushing to reveal texture is desired otherwise walls become too hard after around 60 minutes. Exposed walls should then be water sealed.
In modern variations of the method the rammed earth walls are constructed on top of conventional footings and a reinforced concrete base, usually with extra ground insulation from a horizontal layer of styrofoam.
One of the significant benefits of rammed earth constructions is its excellent thermal mass; it heats up slowly during the day and releases its heat during the evening. This can even out daily temperature variations and reduce the need for air conditioning and heating. On the other hand, rammed earth is not a good insulator. Like brick and concrete (which also have excellent thermal mass), rammed earth must be insulated in colder climates. The thickness and density of the walls lends itself naturally to sound proofing and the materials used in the walls make them virtually fireproof.
Prior to the use of cement as a stabilizer, rammed earth buildings were most successful in dry climates with limited availability of building materials other than earth. Rammed earth has become a viable material in wetter climates, either through the use of cement stabilisation, through placing the earth walls within the weatherproof fabric of the building, or by the application of external insulation and weatherproofing.

Term: Cob

From Wikipedia, the free encyclopedia

Cob is a building material consisting of clay, sand, straw, water, and earth. Cob is fireproof, resistant to seismic activity, and inexpensive. It can be used to create artistic, sculptural forms and has been revived in recent years by the natural building and sustainability movements.

History and usage
Cob-building is a traditional technique that has been used for thousands of years and in all kind of climates. In the U.K. it is most strongly associated with counties of Devon and Cornwall, where many cob cottages have survived and are still lived in. Many old cob buildings can be found in Africa, the Middle East, Wales, and some parts of the eastern United States. The walls of a cob house are necessarily thick, and windows are correspondingly deepset, giving the houses a characteristic internal appearance. The thick walls also provide excellent thermal mass, so that, depending on the climate, cob cottages are relatively easy to keep warm in winter, and tend to be cool in summer. Surprisingly, the material is entirely suitable for rainy climates, and so long as a cob house is reasonably cared for, the structure will not deteriorate; many cob cottages in Devon (one of the wetter counties in England) have been inhabited for hundreds of years. Cob has many similarities to the adobe associated with Mexico and the southwestern United States, but whereas adobe is formed into bricks which are then stacked into a wall system, cob is sculpted from the foundation up.
Where sand is not readily available paper pulp may be added to the clay to minimize cracking when the COB dries.

Modern cob buildings
In 2006, a modern, four-bedroom cob house in Worcestershire, UK, sold for £745 000. Cobtun House was built in 2001 and won the Royal Institute of British Architect's Sustainable Building of the Year award in 2005. The total construction cost was £300 000, but the metre-thick cob outer wall cost only £20 000.

Term: Kia ora

From Wikipedia, the free encyclopedia

Kia ora is a Maori language greeting which has entered New Zealand English. It means literally "be well/healthy" and is used for both "Hello" and "goodbye". It is a popular phrase, and has also given its name to a number of businesses, from hotels to a well known concentrated orange soft drink which is available internationally.
It also signifies agreement with a speaker at a meeting. Other Maori greetings, "Tena koe" (one person), Tena korua (two people) or "Tena koutou" (three or more people) are also widely used, as well as the phrase for goodbye, "Haere ra". The Maori phrase "kia kaha", literally "be strong", is also frequently encountered as an indication of moral support for someone starting a stressful undertaking or otherwise in a difficult situation.
Maori is one of the official languages of New Zealand, the other being English.