In recent years, metal buildings widely used in workshop and warehouse buildings, exhibition halls, and office buildings, which due to the low steel consumption, fast and straightforward installation, and a high degree of industrial production. It promoted the development of the metal cladding system, which from singularity to diversification, and then triggered a change in new design and installed the metal building cladding panel.
The metal cladding system of steel structure building mainly includes wall and roof panel, daylighting panel, trim and flashing, gutter, and insulation cotton. The cladding system is one of the essential components of the prefab metal structure building, which determines the ornamental appearance of the construction, the waterproofing and thermal insulation of the building.
Design and construction of the metal cladding panel systems
1.Classification of the metal panel system
Metal Panel divided into the corrugated single color metal sheet, EPS sandwich boards, GRC wallboards, polyurethane(PU) sandwich boards, glass wool sandwich panel, and rock wool sandwich panel.
According to the construction method, it divides into the sandwich panel, on-site sandwich panel. On-site composite panel connection methods divided into lapboard, bite board, concealed board.
Material: galvanized color steel sheet, aluminized zinc color steel sheet, aluminum alloy profiled plate, stainless steel profiled plate,
On-site composite panels widely used in metal structure building due to their low processing cost and mature construction technology. The roof metal sheet is colorful with the 0.5mm and 0.6mm thick galvanized paint color sheet.
The roof slope affects the discharge of roof rainwater. The roof slope should be 1 / 8-1 / 20 when designing, and the more significant value should take in areas with heavy rain — besides, the roof slope related to the type of roof panel. Generally, the roof slope is substantial for the exposed nail type of board, while it is small for the hidden nail type panel.
Design and construction of the daylighting panel
The daylighting sheet is fixed with self-tapping screws and then glued and sealed. The position of the daylighting panel generally set in the span. The skylight sheet does not need to overlap within 12m. If it exceeds 12m, it needs to overlap. The overlap length is 200-400mm.
The longitudinal and longitudinal overlap of the daylighting sheet should set near the purlin. The waterproofing of the roof must be coated with sealant internally, and the surface of the sealant is smooth to age. The overlapped place uses a white or colorless sealant in the middle.
The Insulation of metal cladding panel
The insulation use rock wool, glass fiber, and other materials. The thermal insulation cotton has excellent thermal insulation performance, convenient construction and installation, energy-saving, and low thermal conductivity. At present, the steel structure roof system mostly adopts (1) steel wire mesh + aluminum foil insulation cotton + corrugated metal sheet, (2) double-layer corrugated metal cladding + insulation cotton.
The following mainly introduces the construction method of steel wire mesh + aluminum foil insulation cotton + single color metal roof cladding:
Cross the stainless steel wire for a diamond or rectangular shape, lay a glass wool roll, the aluminum foil facing the indoor side, perpendicular to the purlin, and leave about 20 cm more Roll the felt and fix it to the outermost purlins with double-sided tape. Finish the glass wool with the reserved 20 cm veneer. Pay attention to the tension and alignment of the glass wool roll, and the seams between rolls are tight. When the overlap required in the longitudinal direction, the overlap joint should arrange at the purlin.
According to the structure, the cornice can divide into three forms: the outer drainage gutter, the inner drainage gutter, and the free fall. Freefall and external drainage gutter can choose preferred. According to the material, there are stainless steel gutters, steel plate gutters, and metal color sheet gutters. Gutter, as the primary drainage system of the roof, determines the function of rain and snow discharge and the regular use of the building roof.
Trim and flashing
Trim and flashing not only outline the building, make the metal building more beautiful, but also connect the building as a whole on the structure, which is windproof and rainproof, making the building more durable.