I have purchased a couple of modules built on a self-supporting steel frame (have received 2 out of 4 modules), but eventually want to make them blend in a bit more by adding a gable roof on top.
I have been considering the best way to solve this without placing a load-bearing wall in the middle of the modules, and preferably at the lowest possible cost. The ideas revolve around conventional trussed roof trusses, which are a bit more expensive but self-supporting; the other option is a ridge beam and rafters with everything resting on steel structures, which would likely be easier to do on one's own. The problem with the latter option is uncertainties about whether the steel construction can handle a point load in the middle instead of a distributed load as the current flat roof provides. It would, however, be acceptable to have a column in the middle transferring the load to the ground, but it would be clearly advantageous without.
Longitudinal steel beams are 275 mm high, I would guess that it most resembles a C-beam in construction. Each module is 3x6 meters, so the span is 6 meters.
I am grateful for any input and ideas regarding this!