The Construction Process of Prefabricated Houses in Japan
The construction process of prefabricated houses in Japan is highly industrialized, mainly divided into five stages: construction preparation, component prefabrication, on-site installation, interior construction, and decoration connection.
Construction Preparation: Construction companies formulate strict construction plans in advance, pre-setting each step of house construction and clarifying daily project progress. The construction site is managed in a standardized manner, clean and tidy. Items such as safety helmets, gloves, and disposable sock covers prepared for visitors are hygienic and considerate, creating favorable conditions for subsequent construction.
Component Prefabrication: A large number of building components are prefabricated in factories, covering multiple aspects. The upper row of reinforcing bars for beams is tied together with the prefabricated components in the factory; formal stairs adopt assembled steel structures; when installing prefabricated columns, the embedded parts for on-site support installation are reserved in the factory in advance; exterior wall tiles are pasted together with prefabricated concrete components in the factory; holes for electromechanical wiring are reserved on beams during factory prefabrication; the embedded parts for connecting tower cranes are also embedded in the prefabrication factory, with each embedded part's screw holes being precise and accurate. Bolts and nuts are marked with diagonal lines using colored pens to ensure accurate installation; the concrete sills of corridor walls have embedded installation holes and connecting iron parts, and the embedded parts required for walls below beams are embedded in the factory; bathrooms are made into industrialized finished products in the factory, with interior wall and floor tiles as well as bathroom decorations all completed.
On-site Installation: This includes main structure installation, wall installation, and exterior wall treatment. During main structure installation, prefabricated components transported to the construction site are assembled on-site. For example, for the joints of prefabricated beam-column components, on-site post-poured concrete is used. A group of workers collaborate to install prefabricated beams, and prefabricated columns are installed on-site; wall installation involves preparing wall panels transported to the floor for installation. The installed balcony wall panels and seismic column joints reflect the precision of construction; exterior wall treatment adopts composite cement boards, installed in a snap-fit manner. When concrete is poured in the middle, it directly adheres to the cement boards. The exterior walls have an additional layer of thermal insulation, and the color can be selected according to needs.
Interior Construction: In terms of electromechanical installation, hooks for hanging electromechanical pipelines are directly adhered to the prefabricated floor slabs. Wires of different colors distinguish different functions. Ground pipelines are fixed using galvanized formed brackets, and drainage riser pipes are wrapped with sound insulation cotton; for sound insulation and thermal insulation treatment, thermal insulation is done indoors using sprayed foam glue, and the floor slab sound insulation design is in place.
Decoration Connection: After the main structure is hoisted and capped, the installation of interior walls, electromechanical construction, and decoration construction are closely and orderly connected, and can be completed quickly.
