Editing Building material (section)

===Mud and clay===
[[File:SkogarMuseumOutside.jpg|thumb|Sod buildings in Iceland]]

Clay based buildings usually come in two distinct types. One being when the walls are made directly with the mud mixture, and the other being walls built by stacking air-dried building blocks called [[Mudbrick|mud bricks]].

Other uses of clay in building is combined with straws to create [[light clay]], [[wattle and daub]], and mud [[plaster]].

====Wet-laid clay walls====
{{Main|rammed earth|sod|cob (building)}}
Wet-laid, or damp, walls are made by using the mud or clay mixture directly without forming blocks and drying them first. The amount of and type of each material in the mixture used leads to different styles of buildings. The deciding factor is usually connected with the quality of the [[soil]] being used. Larger amounts of [[clay]] are usually employed in building with ''cob'', while low-clay soil is usually associated with ''[[sod house]]'' or ''[[sod roof]]'' construction. The other main ingredients include more or less [[sand]]/[[gravel]] and [[straw]]/grasses. ''Rammed earth'' is both an old and newer take on creating walls, once made by compacting clay soils between planks by hand; nowadays [[formwork|forms]] and [[machine|mechanical]] [[pneumatic]] compressors are used.<ref name="Graham">{{cite book |last1=McHenry |first1=Paul Graham |title=Adobe and Rammed Earth Buildings: Design and Construction |date=1984 |publisher=Wiley |isbn=978-0-471-87677-9 |page=104 }}</ref>

Soil, and especially clay, provides good [[thermal mass]]; it is very good at keeping temperatures at a constant level. Homes built with earth tend to be naturally cool in the summer heat and warm in cold weather. Clay holds heat or cold, releasing it over a period of time like stone. Earthen walls change temperature slowly, so artificially raising or lowering the temperature can use more resources than in say a wood built house, but the heat/coolness stays longer.<ref name="Graham" />

People building with mostly dirt and clay, such as cob, sod, and adobe, created homes that have been built for centuries in western and northern Europe, Asia, as well as the rest of the world, and continue to be built, though on a smaller scale. Some of these buildings have remained habitable for hundreds of years.<ref>{{cite book |last1=Smith |first1=Michael G. |chapter=Cob Building, Ancient and Modern |pages=132–133 |editor1-last=Kennedy |editor1-first=Joseph F. |editor2-last=Wanek |editor2-first=Catherine |editor3-last=Smith |editor3-first=Michael G. |title=The Art of Natural Building: Design, Construction, Resources |date=2002 |publisher=New Society Publishers |isbn=978-0-86571-433-5 }}</ref><ref>[https://web.archive.org/web/20100416132054/http://www.takungpao.com/news/10/01/28/_IN-1208245.htm] Earliest Chinese building brick appeared in Xi'an (中國最早磚類建材在西安現身)]. takungpao.com (2010-1-28)</ref>

====Structural clay blocks and bricks====
{{Main|adobe|mudbrick|compressed earth block}}

''Mud-bricks'', also known by their Spanish name ''[[adobe]]'' are ancient building materials with evidence dating back thousands of years BC. ''Compressed earth blocks'' are a more modern type of brick used for building more frequently in [[industrialized society]] since the building blocks can be manufactured off site in a centralized location at a [[brickworks]] and transported to multiple building locations. These blocks can also be monetized more easily and sold.

Structural mud bricks are almost always made using clay, often clay soil and a binder are the only ingredients used, but other ingredients can include sand, lime, concrete, stone and other [[Binder (material)|binders]]. The formed or compressed block is then air dried and can be laid dry or with a mortar or [[clay slip]].