Abstract: The roof of a recreational vehicle is cut away to leave a large opening over the vehicle compartment and an upwardly extendable roof is mounted over the opening. The extendable roof has an upstanding wall fixed to the vehicle around the opening and an upper section has a roof panel with a depending wall receivable in the upstanding wall and having an outwardly extending flange at its lower edge. An intermediate wall section extends around both the depending and the upstanding walls and has upper and lower flanges engageable, respectively, with the flange on the upper section and another flange at the upper edge of the upstanding wall to limit upward movement of the upper section. The intermediate wall has releasably secured ends to permit spreading for assembling the sections of the roof. Swingable links control raising and lowering the roof and a shroud or fairing depends from the outer edge of the roof panel to enclose the wall sections when the roof is lowered.