Construction site: organisation, construction techniques and materials

• The stone, just the stone

In order to harmonize this modern building program with the classic character of the historic city, the choice of a noble and regional material is necessary from the beginning of the project by the exclusive use of the ashlar of the quarries of Fontvieille and Estaillades.  
This is a second choice which may seem anachronistic, after that of the closed composition of the mass plane (cf. : The organization of the building: a modern anachronism), in a transaction related to Industrial sector which advocates heavy prefabrication through the industrialization of construction techniques and materials, such as the use of standardized facade panels.
But the peculiarity of the facades of the City of Beisson lies in the fact that the stones are "pre-cut" in quarry and strictly modulated in their definitive measures of implementation on the site thanks to a mechanical sawing process. By this technique, stone becomes a rationalized and economic industrial component, synonymous with solidity and durability.
This technique of implementation of pre-cut stone facades follows the one implemented by Paul Marcerou^[1] for Fernand Pouillon during the reconstruction of the Port of Marseille.
It constitutes the only element allowing the program to be validated by the M.R.L. within the framework of the Industrial sector, since there is also no heavy prefabrication^[2]. Construction techniques are still traditional.
The construction of this city is thus in line with a local tradition, recently rehabilitated, in 1951, in Aix-en-Provence by Fernand Pouillon during the construction of the Two Hundred Units.

• Structure and construction techniques of the main work

Thesite organization through the establishment of various workshops: a reinforcement workshop (shearing and reinforcement for beams, slabs and walls, welding station; a wooden formwork shop; a prefabrication area for moulds and cast elements; and a concrete plant (Richier type concrete mixer, Pellauto type hand grinder and a cement shack). The transport, moving and lifting of materials on foot are carried out by two Pingon type cranes that move on rails and planks.

• Foundations

The foundations are made up of reinforced concrete soles positioned under the walls of the facades and the longitudinal walls. The buried part is treated in wobbly concrete up to the level of the low floor of the ground floor.

• Facades

Les façades Droplets are pre-cut stones 33 cm thick and 140 cm, 83 cm or 70 cm long. The installation is made with cement mortar; the joints are full, made with a mortar of oily lime married to stone powder of the same nature.
The lining of the walls is provided with an air gap of 4 cm and at the back a brick partition^[3] 3 cm in mortar and plaster.
A stone cladding forms the entablature.
The gables are either blind and covered in stone, or embellished with slender balconies.

• The floors

Les floors are made of reinforced concrete with a overhang on the façade originally intended to remain rough. However, the differences in tone after drying required the application of a grey vinyl paint as close as possible to the natural shade of the raw concrete. 
The sound insulation is provided by a layer of "Sordonit" which is an alloy of cork, bitumen and wool felt.

• The partitions

The separative walls of the apartments are made of masonry from 15 cm hollow block blocks.
The interior separations are made by 5 cm brick partitions.

• The roof terraces

Les roof terraces are made of reinforced concrete slabs sealed with a multilayer coating. Thermal insulation is provided by a 10 cm layer of vermiculite concrete.

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[1] Director of Careers of Fontvieille.
[2] Except reinforced concrete stair steps and risers, which are prefabricated.
[3] Otherwise called in the execution project: Poop partition. Wall lining technique used before the appearance of plasterboard type Plasterboard.