The altarpiece made from oak comprises three independent modules: the centre module (the Coronation relief) has vertical dividing pillars on both sides, the left-hand module contains the Pentecost relief and the right-hand module the Last Supper. All three were originally joined together by "Y"-shaped metal plates and through bolts.
Several vertical split panels joined together simple butt joints reinforced by crossbeams make up the rears of the compartments, but leave their lower sections open. Corner joints are dove-tailed and doweled. Architectural decorations are made up of several superimposed pieces making up one single piece as a whole.
The 23 carved groups are mostly made from one single piece of wood that is occasionally complemented with small additional pieces. The Last Supper, however, is made up of multiple fragments. Several pieces show the characteristic marks of gouges to their rears that are found so typically in Baltic oak. Wooden blocks are also used to provide greater help stability and increase the height of the figures.