Mechanical properties of adobe walls in a Roman Republican domus at Suasa

Cob Construction in Italy: Some Lessons from the Past

“…No straw was found in the core of the taken samples, but was only on the external surface, probably to limit the considerable shrinkage of the material [4]. Straw, in fact, can reduce hygrometric shrinkage because of both its tensile strength and, above all, its slow water release capability [3].…”

“…It has the texture [21], and the limits of consistency [22] reported in Table 1. As a building material, its water content ranged from 6 to 10%, with a dry specific density equal to 1,860 kg/m 3 . No straw was found in the core of the taken samples, but was only on the external surface, probably to limit the considerable shrinkage of the material [4].…”

“…In order to estimate the cost of the cob masonries per m 3 , with reference to residential buildings, we determined the cost to make a single cob brick and the cost to build a 1 m 3 cob wall, considering that at least 600 cob bricks are needed to build it. If we consider to employ common workers to form hand-molded cob bricks and to use earth coming from a local quarry, the estimated cost for each cob brick (Table 4) amounts to 0.70 €, which also included the general costs and establishment's profit.…”

“…In order to estimate the cob masonry unitary price per m 3 we considered the unitary cost of various production factors and their quantity. In general, we defined the unitary price of a phase as the sum of the following terms:  general costs for the initial preparation of the building area, which was considered equal to 10% of the sum of materials and manpower costs;  establishment profit, which was considered equal to 15% of the sum of the costs of materials, manpower and of the general costs.…”

“…As has been happening in other countries for several years [1][2][3][4][5][6][7][8][9][10], in Italy too, there is now a renewed interest in raw-earth constructions (see for example: the Italian bill dated 14/02/2002 titled "Normative to support raw-earth buildings and raw-earth as a building material"). Raw-earth constructions are, in fact, environmentally-friendly and highly bio-sustainable.…”