Slip form paver and method for adapting the width of a screed

In a slipform paver with a tractor including a machine frame with longitudinal members and telescopable cross members, the machine frame comprises a central frame module in which the cross members are supported in a telescopable fashion. A mold adjustable to the working width comprises at least one permanent central mold element fixed relative to the central frame module and at least one permanent outer mold element movable relative to the central frame module. The permanent outer mold element is permanently attached to one of the cross members and/or one of the longitudinal members and the outer mold element is movable together with the cross member and/or the longitudinal member during the adjustment of the working width of the machine frame.