ENCLOSURE STRUCTURES

A wide range of facade systems and forms can be created using steel structures, including stained glass, curved and sloping walls. 

Facade materials can be combines to increase the aesthetic appearance of the building. 

The choice of wall and roof cladding can significantly affect the appearance of the building, namely: the shape of the profile, color, fastenings, orientation of the cladding (horizontal or vertical ribs). A potential disadvantage of horizontal ribs is the fact that they tend to accumulate dirt over time, unless the cladding is cleaned regularly. 

If the location and functions of the building require a smooth outer surface, insulated wall panels with flat cladding sheets are used, however, it should be noted that any defect on the surface will be easily noticeable.

The steel of which the corrugated cladding sheets are made is pre-coated with the use of a wide range of colors and textures, allowing architects to choose the option that best suits the location and function of the building. 

The general appearance of the building can also influence the choice of fasteners, especially in the case of wall cladding or the roof with a large slope. There are fasteners with factory colored plastic heads to match the color of the cladding. If the fasteners are considered detrimental to the appearance of the building, the architect may consider the possibility of the use of hidden fasteners. 

Enclosing structures of walls and roofs in buildings with a steel frame are most often used in the form of panels of metal corrugated sheets, which are divided as follows by the installation method:

• Factory-made panels, which are delivered ready-made and can be enlarged into cards before installation.

• Composite panels, which are assembled element by element directly on the construction site from two corrugated sheets, between which steel dividing elements are installed and hydro, heat and steam insulation is arranged.

Composite panels are usually used to form the roof, while the use of factory-made panels is better suited for wall enclosing structures. 

The advantage of composite enclosing panels is the possibility of assembly of the components depending on the construction conditions, which allows to achieve the required span lengths and thermal insulation properties. Corrugated sheet systems also make it possible to arrange ventilated facades and internal partitions of buildings.

Stiff polystyrene or polyurethane foam glued between two corrugated sheets is used as insulation in factory-made panels. The ends of panels are also taped with insulation tape and are arranged in such a way as to create tight joints upon assembly, which excludes any cold bridges. Panels are fastened to the basic bearing structures by using special connecting elements on bolts that exclude the break of airtightness of the panel.

Products intended for use in the installation of covering, as well as floors and walls of public and industrial buildings and structures, or for external or internal cladding of the premises are manufactured in accordance with DSTU 8802: 2018. In the case of voluntary application, this standard is proof of conformity of products to requirements of the Technical Regulation of construction products, buildings and structures. Conformity of products to the established requirements can be confirmed by the manufacturer by the method of preparation of the appropriate declaration or certificate issued by the conformity assessment body (CAB).

By their purpose, products are divided into:

• corrugated sheets for flooring and cassettes — PN (can be used as casing during the installation of floors with the use of concrete), KS;

• corrugated sheets for wall cladding (surface finishing) and cassettes — PS, KS;

• roofing stamped sheets with longitude ridges (metal tile sheet) - MCh;

• flat or corrugated, bent U-shaped roofing sheets (folded corrugated sheets)— PF.

By the materials of the original piece products, products are divided into:

• corrugated sheets of rolled steel with a metalized coating (flat sheet or bar with a thickness of 0.4 mm to 4.0 mm inclusive for cold forming with a metalized coating applied on the production line by immersion in the hot melt of zinc (type Z), zinc-aluminum (type ZA), aluminum-zinc (type AZ)) according to DSTU EN 10346;

• corrugated sheets of the core material with an organic protective and decorative coating applied in continuous lines on one or both sides of the steel sheet in one or more layers in accordance with DSTU B B.2.7-58, DSTU EN 10169.

Example of product symbols:

1. Manufacturer's name;

2. Product type or brand;

3. Product parameters (B — effective width of the product, h — ridge height, t — thickness of the original piece product); 

4. The material of the original piece product according to clause 4.2.6; 4.2.7 DSTU 8802: 2018;

5. Type and thickness according to clause 4.2.11 of DSTU 8802: 2018.

Example of marking

Manufacturer (name/brand), PN type product with ridge h = 60 mm, thickness of the original piece product t = 0.7 mm, steel S320GD + Z100 with the coating of the front surface — "polyester" PE 15 μm.

"Manufacturer" — PN60-0,7S320GD + Z100 PE15

To determine the conformity of rolled products used for the manufacture of products to the requirements of the standard, the manufacturer carries out incoming control of raw materials based on the accompanying documents (certificate, technical data sheet, etc.) for rolled products, confirming the brand, chemical composition and mechanical properties of steel, type and thickness of the metal coating, and for OP — type, thickness, color, quality indicators of adhesion, resistance to cracking upon bending and pencil hardness test. If necessary, upon request, the manufacturer may obtain from the supplier the report on laboratory tests of the quality of the coating or perform such tests in accordance with the requirements of DSTU EN 13523. 

The surface quality of the protective coating (metalized or OP) of products of any type is determined visually by comparison with reference samples.

With the development of process capacities of rolling, the availability of different steel thicknesses from 0.5 to 1.5 mm, as well as the possibility of using high-strength structural steel grades, make it possible to produce a corrugated sheet with greater ridge height, which can cover spans up to 9 m. 

Due to this, it is possible to eliminate the use of roof joists and install the load-bearing profile directly on the roofing elements (beams, trusses), which reduces the metal content of the roof and installation time. 

When conducting tenders for the supply of enclosing structures, the essential characteristics of the products must be considered: mechanical resistance, water permeability, change of sizes, emission of hazardous substances, reaction to fire, resistance to external fire, durability according to DSTU B EN 14782/DSTU 8802.