T35 is a profile chosen for roofs and cladding requiring a greater profile height than T18. However, the suitability of the sheet is determined by the entire cross-section, thickness and steel grade. The symbol alone does not specify the permissible support spacing. Before purchase, the coverage width, profile side and installation conditions must also be established. This allows products to be compared without confusing the dimensions and load-bearing capacities of different variants. Sheet with this profile can be found on garages, agricultural buildings, workshops and halls. It is also sometimes used on façades. Its pronounced ribs give the surface a technical character. From a design perspective, however, transferring loads to the purlins or battens is more important than appearance.

What matters is whether the trapezoidal sheet merely encloses the building or also carries loads within the roof structure. In the first case, check above all wind action and the permissible deflection; in the second, check selection for loads in accordance with the design. Profile height alone does not determine suitability; steel grade and thickness, the support scheme and the connections all count. Review the load table for the relevant scheme and conditions, and also consider openings, insulation and surface protection. Leave final design decisions to the designer.

Trapezoidal sheet metal can suit a traditional-style house if its profile, colour and details work with the building form and surroundings. Rather than following a generic recommendation, assess the whole composition: roof proportions, eaves, chimney and façade materials. Check whether the chosen variant disrupts the existing arrangement and whether its technical parameters match the structure and pitch. Compare samples under different lighting conditions and analyse the details at the roof edges. The decision should come from fitting the specific building, not from the name of the covering alone.

T18 trapezoidal steel sheet is suitable for many roofs and façades, but the profile name alone is not enough to place an order. You need to check the cover width, steel thickness and sheet variant. The support spacing depends on the loads and the tables for the specific product. Two sheets marked T18 may have a different width, a different cross-section and different installation conditions. Below we show how to read this data and use it when taking measurements. The number in the name refers to the nominal height of the rib. It does not describe the steel thickness, sheet length or cover width. T18 from two different production lines does not have to have identical ribs.