A second carcass is formed by using aluminum profiles on the main carrier steel construction. Glass or opaque materials in suitable sizes are adapted into this carcass. Depending on the openings passed, system solutions can be made with aluminum profiles without the main carrier steel construction. Profile sections are dimensioned by calculating snow, wind and live loads in skylights depending on the relevant norms and local regulations. The rainwater drainage and cleaning system must be thawed. Smoke evacuation or ventilation windows can be opened into skylight systems.