ᐅ Adding an additional floor to a single-story wooden house elevated on stilts.

Hello,

I would like to add an additional floor to a 40-year-old wooden house with a flat roof and a footprint of 80 sqm (860 sq ft). The zoning plan only allows a setback floor of 40 sqm (430 sq ft). An extension is not possible.

I want to keep the house as it is and avoid interfering with the building’s structural frame as much as possible. My current idea is to build a 40 sqm (430 sq ft) floor on stilts above the house. It might be necessary to install one stilt through the roof of the old house. The first floor would be accessed via an external staircase.

Is this concept fundamentally feasible or completely unrealistic?

I would appreciate any assessment.

Best regards

charly12345