<P> Depending on the form into which the mixture is pressed, adobe can encompass nearly any shape or size, provided drying is even and the mixture includes reinforcement for larger bricks . Reinforcement can include manure, straw, cement, rebar or wooden posts . Experience has shown straw, cement, or manure added to a standard adobe mixture can all produce a stronger, more crack - resistant brick . A test is done on the soil content first . To do so, a sample of the soil is mixed into a clear container with some water, creating an almost completely saturated liquid . The container is shaken vigorously for one minute . It is then allowed to settle for a day until the soil has settled into layers . Heavier particles settle out first, sand above, silt above that and very fine clay and organic matter will stay in suspension for days . After the water has cleared, percentages of the various particles can be determined . Fifty to 60 percent sand and 35 to 40 percent clay will yield strong bricks . The Cooperative State Research, Education, and Extension Service at New Mexico State University recommends a mix of not more than 1 / 3 clay, not less than 1 / 2 sand, and never more than 1 / 3 silt . </P> <P> The ground supporting an adobe structure should be compressed, as the weight of adobe wall is significant and foundation settling may cause cracking of the wall . Footing depth is to below the ground frost level . The footing and stem wall are commonly 24 and 14 inches thick, respectively . Modern construction codes call for the use of reinforcing steel in the footing and stem wall . Adobe bricks are laid by course . Adobe walls usually never rise above two stories as they are load bearing and adobe has low structural strength . When creating window and door openings, a lintel is placed on top of the opening to support the bricks above . Atop the last courses of brick, bond beams made of heavy wood beams or modern reinforced concrete are laid to provide a horizontal bearing plate for the roof beams and to redistribute lateral earthquake loads to shear walls more able to carry the forces . To protect the interior and exterior adobe walls, finishes such as mud plaster, whitewash or stucco can be applied . These protect the adobe wall from water damage, but need to be reapplied periodically . Alternatively, the walls can be finished with other nontraditional plasters that provide longer protection . Bricks made with stabilized adobe generally do not need protection of plasters . </P> <P> The traditional adobe roof has been constructed using a mixture of soil / clay, water, sand and organic materials . The mixture was then formed and pressed into wood forms, producing rows of dried earth bricks that would then be laid across a support structure of wood and plastered into place with more adobe . </P> <P> Depending on the materials available, a roof may be assembled using wood or metal beams to create a framework to begin layering adobe bricks . Depending on the thickness of the adobe bricks, the framework has been preformed using a steel framing and a layering of a metal fencing or wiring over the framework to allow an even load as masses of adobe are spread across the metal fencing like cob and allowed to air dry accordingly . This method was demonstrated with an adobe blend heavily impregnated with cement to allow even drying and prevent cracking . </P>

This architectural term means a structure created from a pile of material