A monumental apartment block from the fifties, in property of 32 different owners needed a renovation. Especially the window frames with single glass in it created a lot of condense and sound problems. After extensive research whereby different options were inspected and a lot of communication was done with local government authorities, we decided to remove the existing window frames with aluminium frames . The renovation profile CS24-SL from Reynaers was chosen because it matched the most the image of a slim frame, resembling the old window frames. After color research the authentic color was determined and applied on the new frames. All wooden entranced and terrace doors are also renewed when that was necessary , the roof is insulated and accommodated with new roof tiles. By intensive dialog we got all house owners and authorities harmonised and the monument is shining in full glory again.