14C-dating of wooden buildings in Flanders (Belgium). A problem of reliability?

From the Prehistory until the Late Middle Ages wood was the most important construction material for buildings in Flanders. With the exception of wet contexts, the wooden posts of the structures are not preserved anymore. Because of this, these buildings are difficult to date. Charcoal or charred grains preserved in these postholes are a dating option, although the origin of these materials is not always clear. To tackle this problem of reliability, a strategy is to date several samples from the postholes of the same structure. A pattern of contemporaneous 14C-data will give us insight in the age of these structures and outliers can be eliminated. To verify the results of the 14C-dating a comparison is made with the fragments of material culture recorded in the infill of the postholes. This method has resulted in the recognition and dating of buildings types during Protohistory and in the Roman period in Flanders and the adjoining regions.