Utilization of Lightweight Steel Frame that briefly named LSFmostly used for maximum 5 floors buildings with residential, hospital, official and training applications.
LSF is one of the new technologies in civil construction field of the country and presents specifications such as significant weight loss, high speed construction and installation, increased safety against lateral loads, increased damp proof course and increased sound and heat insulations.
Prefabricated buildings with Lightweight Steel Frame (LSF) method get used dry run and mostly with the use of screw fittings and industrial production method. These buildings are formed from three main parts consisting of cold rolled steel sheets for structures, cement and plaster boards as cover for internal and external surfaces, and heat and sound insulations. LSF method in building construction has been utilized since 1950 in Canada, and has found a special place in building construction industry of developed countries because of owing many benefits such as high construction quality and appropriate seismic performance. In addition to developed countries, this method has been propounded in many other countries in the world.
This method has proved itself very well and at the present it is one of the fastest construction methods.
Cold rolled thin sections are lightweight and rigid and offer the highest ratio of resistance to weight in comparison with other building materials. Moreover, used panels are produced from specific methods in the factory and thus the ratio mentioned above is also raised. Therefore, structural weight in this method decreased by 50 percent on average compared with other prevalent methods.
This system resists against gravity and lateral loads (wind and earthquake) which determined according to national building regulations of Iran. It is essential to note that as owing to a significant decrease in weight of buildings, the lateral load caused by earthquake is reduced and therefore this system offers a very appropriate seismic performance.
Lightness of components and simplicity of assembly and system applicability in all weather conditions and also, providing the working possibility of other building groups simultaneously and in parallel, the construction time is minimum. Owing to utilizing plaster and cement panels, building finishing operations are done fast and with a high quality. Consequently, it causes a significant reduction in construction time and rapid return on initial investment accordingly.
According to appropriate cover of structural elements, even with forming steel sheet for constructing desired sections, no cracks or other damages created on the cover. This type of cover causes high resistance against humidity, climatic and physical factors. Composing elements of the building have no attraction for insect invasions.
For the reason of filling the space between panels with proper insulations such as rock wool and polyurethane foam, even in comparison with traditional made buildings, this system highly meets the 19th section of Iran's National Building Regulations. Furthermore, proper sound performance in internal spaces is the other advantage of this system.
None of the composing elements isinflammable. Owing to covering structural elements with fire resistant prefabricated panels, structure in this system has outstanding fire-resistance.
There is an ability of recycling materials. It is required to mention that waste and residual materials are minimal during building construction.
All facilities in this system are simply accessible which cause a substantial reduction in maintenance cost of them. In addition, as for reducing construction costs and also appropriate heat transfer resistance that causes a considerable decrease in construction and operating costs, this system presents a very reasonable option for building constructions.
As for relatively low weight of LSF system, by taking necessary cautions and measures, there are possibilities of adding to floors of existing buildings and it is the best system in this regard.
Composing elements of LSF system are lightweight and therefore material parts are simply carried and replaced in different sections of a project.
Ease in construction and installation of facilities
By offering structural materials list, required parts produced according to project specifications and geometry in a short time in the factory and thus construction and installation of structures are done with a considerable reduction in the volume of operations and manpower.
Materials used in this system have no harm to the environment as it requires less traffic and transport at the project site during construction and also used materials can be reproduced for reuse.
Design diversity and building construction with different views;
Simplicity in prefabricating and mass production;
Quick and easy installation;
High precision in construction;
Increased building surface area because of wall thickness reduction;
Ability to combine different types of lightweight and new materials with traditional materials;
No need to formatting;
No existence of creep and drop in ambient temperature;
Ability to install all kinds of windows in this system;
The possibility of changes in details of work;
Less workshop space occupation;
Since there is no need to special equipment, there is more safety in workshop;
Flexibility in design because of high possibility of construction and production of all kinds of profiles;
Diversity in building face design owing to ability to utilize a variety of types of façade materials;
Meeting requirements and standards regarding building performance;
According to production method of the elements, profiles are similar in terms of dimensions and shapes.