The application of rigid frame joints with tapered plates at the edges and high-strength prestressed bolts avoiding any kind of stiffeners makes use of several well-known methods of construction to reduce the time required for the welding process. A total of 31 tests on frame joints of IPE profiles with the mechanical properties of St 37 and StE 460 steels were made. A simple method for calculating unstiffened frame joints is suggested and compared with test results.