the post 32 is cut at an angle to conform to the upper edge of the rafters 26 an aperture 54 is formed in the king post 32 between oppositely directed side faces 55 57 to receive one end of the front ridge beam 34 similarly an aperture 56 is formed between the side faces 55 57 intermediate the ridge beam 22 and the aperture 54 to receive the rear ridge beam 36 the apertures 54 56 are similar in construction although oriented in opposite directions referring therefore to fig8 the aperture 54 has a through mortice 58 dimensioned to receive a tail portion of the ridge beam 34 as will be described in more detail below a rabbet 62 is formed around the mortice 58 in the side face 55 facing the front ridge beam 34 it will be appreciated that a similar rabbet 64 is formed in a mortice 66 forming aperture 56 in the face 57 to receive the rear ridge beam 36 the periphery of the rabbets 62 64 correspond to the cross section of the respective ridge beams 34 36 each of the ridge beams 36 38 has a tail portion 60 as can be seen in fig6 that is formed by removing the flanks of the ridge beams by a thickness corresponding to the width of the rabbet 62 so that the tails 60.