In the field of prefabricated construction with dry systems, Manni Green Tech has been carrying out research and testing for years in order to provide builders and clients with products that enable the construction of buildings quickly, at a certain cost, and that guarantee the best environmental comfort.
With this in mind, the lightweight load-bearing structures of the Light Steel Frame system, made from cold-rolled steel profiles, are proving in the field to be the best solution for meeting the demands that modern building and living entails.
In order to make the advantages of the LSF system evident, we will now illustrate a case history concerning a residential building in the province of Vicenza, Villa Sovizzo.
The client's request was to build a house for two families, with a total area of 550 square metres.
The use of Manni Green Tech's LSF dry system proved to be the ideal solution to best meet the various requirements, aesthetic-formal, environmental comfort and reduced construction time, both at the design stage and during the construction of the building.
The client did not want to realise the typical house with a pitched roof, but an avowedly modern building, with a building volume that would generate movement to the facades of the villa. The modularity of the LSF dry system gave the designers great freedom, allowing them to create large, well-lit spaces, resulting in non-traditional architecture with projecting volumes and large windows.
The client has complete freedom to design his own architectural project.
MGT's real strength is adapting its construction system to the architectural design received. This is thanks to MGT's technical team working alongside the architect in charge of the villa project from the earliest stages, thus achieving high levels of design integration.
No less important is the client's request for certain and short construction times, while at the same time avoiding the possibility of 'surprises', and additional costs, of various kinds during the construction stages.
Precise design by Manni Green Tech's technical department of every component of the building using CAD and BIM software resulted in a fully defined project in all its structural features and detailed metric calculations that gave no surprises during construction.
With the use of the LSF system, it took only 45 days from the start of profile production to the completion of the structures, confirming a tangible speed and agility on site.
The lightness of the LSF system had a positive impact on the timing and cost of foundation construction. In fact, a simple foundation slab was built in which the LSF profile grafts were prepared, avoiding deep excavations.
The entire structure was made of lightweight cold-formed steel profiles, in structural collaboration with hot-rolled reinforcing elements.
On site, the elements all arrive pre-assembled off-site with an installation kit included in transport. Assembly drawings are also enclosed and the structures are installed following the 'instructions' delivered by us. The entire system is installed dry, i.e. without the use of water, and all elements are screwed, not welded. All this increases site safety in the execution of works and speeds up the construction stages.
ISOPAN sandwich panels and Manni Green Tech sheets are simply screwed directly onto wall profiles and floor joists. The lightness of the elements allows for installation teams of 2-3 workers, thus optimising labour and safety costs.
In some cases, scaffolding or site cranes are not necessary because the structures can be placed on top of each other using a forklift truck.
In sum, the advantages are:
Another design challenge brilliantly solved with the use of the LSF dry system was climate. Northeastern Italy is characterised by humid summers and cold, rainy winters, so careful design of the enclosure was necessary to ensure environmental comfort in the different seasons of the year.
The choice, not only aesthetically speaking, to make large openings on all sides of the villa, together with a controlled mechanical ventilation system perfectly integrated into the structural meshwork of the building, made it possible to achieve excellent air quality.
The ability to intervene in advance on problems or interference caused by structures and installations by solving the problem right from the design stage.
The architectural design is integrated with the structural design and is checked to ensure that the form and structure are built ad hoc.
Walls and floors were insulated with mineral wool inserted into the thickness of the structure profiles. This type of insulation ensures optimal thermal comfort for both summer and winter; in addition, the solution used ensures acoustic comfort.
The attention paid to the building enclosure during the design stage has resulted in a low overall primary energy requirement, also thanks to the installation of photovoltaic panels on the flat roofing.
The building enclosure designed with the LSF system enabled the building to obtain the CASA CLIMA Class A certificate, and the silver plaque.
Winter heating and summer cooling are provided by a heat pump system with air-water heat exchange, with fan coils installed in each room of the building.
Generally speaking, we can say that our structures maintain a structural 'core' that is always intact and a counter-wall is created for the plant engineering part. In the case of holes for the electrical or plumbing system, this can be done in the service wall while maintaining the performance of the 'core' unchanged.
In addition, all Manni Green Tech profiles already provide a technical hole for the passage of electrical cables should this be necessary. Compared to other traditional technologies here the core retains its thermal and acoustic performance characteristics.
Manni Green Tech's decision to use recycled material for the production of LSF profiles meets the theme of environmental sustainability, and also fulfils the directives of UNI EN ISO 14021:2016.
The choice of a dry system such as LSF also minimises water consumption on the construction site, as water was only used for the construction of the foundation plate.