A connection arrangement for connecting a vertical element, such as a column or a wall element, and a beam to each other, the connection arrangement comprising: - a beam part to be fastened to an end of the beam, which beam part comprises an end plate in which there is a downwardly open slot, at the bottom of which there is an abutment surface, and - a column part to be fastened to the vertical element, which column part comprises a tongue part having a support surface against which the abutment surface of the slot is arranged to be supported in order to receive a vertical load, wherein- in an upper part of the slot, on opposite sides, there are upper abutment surfaces, and in a lower part of the slot there are, on opposite sides, lower abutment surfaces, the horizontal distance between which lower abutment surfaces is greater than between the upper abutment surfaces, - in an upper part of the tongue part there are, on opposite sides, upper support surfaces, against one of which the upper abutment surface of the slot is arranged to be supported when the beam part has been installed onto the column part and a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part, and - in a lower part of the tongue part, on opposite sides, there are lower support surfaces, the horizontal distance between which is greater than between the upper support surfaces and against one of which the lower abutment surface of the slot is arranged to be supported when the beam part has been installed onto the column part and a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part, characterized in that - the lower abutment surfaces of the slot are partly vertical and the lower support surfaces of the tongue part are partly vertical, - the column part comprises a fastening part provided with an internal thread and the beam part comprises a horizontal plate provided with a screw hole, through which screw hole a screw is turned onto the thread of the fastening part to prevent horizontal and vertical movement between the column part and the beam part, - the beam part comprises a U-shaped housing, the ends of its sides being fastened to the back surface of the end plate on either side of the slot, and - the horizontal plate is arranged in a space defined by the housing and the end plate and fastened to the housing and to the back surface of the end plate. - a beam part to be fastened to an end of the beam, which beam part comprises an end plate in which there is a downwardly open slot, at the bottom of which there is an abutment surface, and - a column part to be fastened to the vertical element, which column part comprises a tongue part having a support surface against which the abutment surface of the slot is arranged to be supported in order to receive a vertical load, - in an upper part of the tongue part there are, on opposite sides, upper support surfaces, against one of which the upper abutment surface of the slot is arranged to be supported when the beam part has been installed onto the column part and a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part, and - in a lower part of the tongue part, on opposite sides, there are lower support surfaces, the horizontal distance between which is greater than between the upper support surfaces and against one of which the lower abutment surface of the slot is arranged to be supported when the beam part has been installed onto the column part and a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part, characterized in that - the lower abutment surfaces of the slot are partly vertical and the lower support surfaces of the tongue part are partly vertical, - the column part comprises a fastening part provided with an internal thread and the beam part comprises a horizontal plate provided with a screw hole, through which screw hole a screw is turned onto the thread of the fastening part to prevent horizontal and vertical movement between the column part and the beam part, - the beam part comprises a U-shaped housing, the ends of its sides being fastened to the back surface of the end plate on either side of the slot, and - the horizontal plate is arranged in a space defined by the housing and the end plate and fastened to the housing and to the back surface of the end plate.