5-room floor plans: family plus an extra room

On the ground floor it is most valuable: there it works as an office with a short route to the door, as a guest room next to the shower bathroom – and in old age as a full bedroom that makes the house single-level habitable without conversion. Planned upstairs, it is closer to the children's rooms and better suited as a playroom or third children's room. Many floor plans offer both variants of the same model.

From about 120 m² it becomes comfortable: after subtracting the living area, bathroom, guest toilet and circulation areas, 10 to 14 m² remain for each of the four sleeping and study rooms. Below 115 m² the individual rooms become small, above 150 m² mainly the living area and ancillary rooms grow with it. The bulk of demand lies between 125 and 145 m².

Turnkey in 2026, usually EUR 290,000 to 400,000, driven by living area, construction method and fittings – the room itself costs hardly extra, the area needed for it does. Anyone who gains the fifth room through a clever layout rather than 15 m² of extra area saves around EUR 40,000. Figures exclude land and ancillary construction costs.