New construction of balcony - steel or reinforced concrete?

Hello everyone,

we are currently planning the balcony for our new building. It is supposed to wrap around the corner of our house. The lengths are each approximately 4.5m. Depth 3m or 1.5m depending on the side.

Originally, a steel construction was planned. We would have attached it to the ceiling with metal components and Thermostop inserts. Our shell builder has now also suggested building the balcony out of concrete as an alternative. For funding purposes, we would then have to carry out the entire attachment to the house with insulation baskets (approx. 10 linear meters).

The deciding factor for us will be the costs. Maybe someone can give us a rough estimate here of which option will probably be cheaper.

I would include that in the tender as a contingent item with additional and reduced costs. Then you have definite costs. It probably depends on the company. A master bricklayer probably prefers to do that in concrete.