Mass modular production

Eyeing volume production of finished, precast concrete modules, Compact Habit S.L of Spain has introduced the eMii System (the Spanish acronym for “integral industrialized modular building”). The company is currently in discussions with precast producers, general contractors and developers for prospective system licensees in North America.

As a sustainable system based on repeating units of varying sizes and heights of up to eight floors, eMii’s scope ranges from medical facilities to multi-family dwellings, hotels, schools, and other institutional markets. The system entails manufacturing large, three-dimensional monolithic modules of reinforced concrete. They follow an assembly process of the various components, building services and materials until they leave the production facility fully equipped and with the interior finished to customer specifications.

Shape and material
After analyzing the way to best optimize construction of a room module from industrial elements, Compact Habit considered the use of a three-dimensional container as a structural piece that can be stacked without auxiliary supports. If other determining factors were added for the containers, such as fire protection, construction economy, and mass for sound insulation, reinforced concrete would be the obvious material choice. Its quality, composition, flow characteristics, potential for high compressive strength formulation, and steel reinforcement enable optimization of thicknesses that may reach 5.2 cm in the slenderest areas.

The container is a monolithic rectangular prism with a smooth-finished floors and walls, plus ribbed ceilings. This reflects structural needs in accordance with the calculation model analyzed by the finite element method and second-order theory. Everything is conceived to obtain the maximum optimization of resources, eMii engineers contend.

The production solution adopted for the Compact Habit module is construction of a single piece of concrete in two braced stages. To achieve this, a mold was developed, as was proprietary formwork that enables horizontal concreting phases, thereby solving the problem of mix placement from above. The mechanical formwork can be adapted to different sizes of both length and width.

Structural concept
eMii developers believe the system represents a great change in the current way of building and this will enable a technical evolution that gives many possible variations depending on market needs. As a condition of design and a top priority, they propose that all industrialized modules should be independent from each other, coming in contact only through flexible elements that impede the direct transmission of sound and encourage insulation.

Other design conditions proposed and included in the project:

  • Minimal useful dimensions, which avoid assembly joints that obligate one to work within the area where all the finishes have been installed.
  • Weight of the entire unit, transportable and liftable with heavy-duty cranes.
  • Possibilities of adapting to different sizes according to the project.
  • Solidity of the assembly; no flimsy solutions.
  • Self-supporting module without auxiliary structures.
  • Improved durability due to the type of concrete.
  • Reduction of labor risks and greater workplace safety.

Developer-cited benefits can be broken down into several categories: professional, technical, manufacturing, building, economy, use, and disassembly.

Professional: Allows for the configuration of dwellings from 376 sq. ft. with a single space, also with one to four or more rooms and surface area according to its use; optimization of interior space; multi-use and applicable to buildings used for dwellings, student dorms, hospitals, etc.; and, minimizes technicians’ responsibilities in calculations and execution of the structure.

Technical items: Overall energy savings in system production and building operations phases; excellent sound-proofing; and, surrounding thermal insulation. Pertaining to the risk of fire, there is always a double seal with a chamber between modules that hinders the spread of the fire. Also, affected modules can be substituted out, making repair easy.

Manufacturing: Possibility of improving productivity and, therefore, costs (based on production volume); reduction in workplace accidents; improvements in work quality and work conditions; quality control of each one of the operations and final controls; ease in controlling wastes in the factory; module leaves the factory completely finished and equipped; and, monitoring of the manufacturing of each module is made possible, right down to the finest detail, giving them a personalized quality, before and after manufacturing, and for their entire service life.

Building: Can be built up to a height of eight stories; disassembly or relocation; extremely rapid building; and, annoyances and noise are minimized during the building process.

Economy: Makes economy of scale possible, and prevents cost deviations.

Use: Can be guaranteed like other industrial products; makes possible a thorough monitoring and application of the maintenance plan; facilitates repairs because there are no embedded building services; and, possibility of replacing the pieces, as in the industrial field.

Disassembly without Demolition: Possibility of relocating the building; moving the unit to the factory for modernization and adaptation; and, the ease of separation and recycling of the materials.

— Portland, Me.-based Ned Flint is representing Compact Habit in North America; 207/232-8816; [email protected]