Build attic is I-beam good or H-steel good

Their own attic is recommended to choose the I-beam, and is to choose the national standard steel, because the non-national standard steel in more impurities. I-beam is a section of mechanical properties more excellent economic section steel I-beam features: wide flange, lateral stiffness. Strong bending resistance. The two surfaces of the flange are parallel to each other, which makes the connection, processing and installation easy. Compared with general section steel, it has low cost, high precision, small residual stress, no need for expensive welding materials and weld testing, saving about 30% of steel structure production cost. Under the same section load. The weight of hot rolled H-steel structure is 15-20% less than that of traditional structure. Compared with concrete structure, I-beam steel structure can increase the use area by 6%, while the structural weight is reduced by 20% to 30%, reducing the structural design internal force. I-beam can be processed into T-beam, and honeycomb beams can be combined to form various cross-section forms, which greatly meets the needs of engineering design and production. Channel steel: belongs to the construction and mechanical carbon structural steel, is a complex section of the section steel. Characteristics of channel steel: Channel steel can change the force structure of the building, saving building materials. Channel steel construction, if fast, that is built that use, do not need to wait. Shortcomings: is the attic made of channel steel when people walk on it, there will be a certain shaking sound. (The smaller the channel steel specification, the greater the shaking sound. (The larger the channel steel specification, the smaller the shaking sound.)