Torentje roof structure discovered to be 500 years old

During renovations at the Binnenhof in The Hague, researchers discovered a nearly 500-year-old oak roof construction inside the Torentje, the official office of the Dutch Prime Minister. The discovery was made during a routine asbestos inspection when the ceiling of the Prime Minister's office was opened.

Dendrochronological analysis of the wood revealed that the oak beams and wooden pegs were harvested in southern Sweden and transported to the Netherlands as a complete kit. The research, which utilized tree-ring patterns as a ‘fingerprint,’ determined the wood was felled in the autumn of 1546 or 1547. This finding was corroborated by historical documents, including a 1547 invoice for renovation materials.

Experts from the Rijksvastgoedbedrijf noted the rarity of such well-preserved original structures, as many other parts of the Binnenhof underwent significant replacements during the 19th and early 20th centuries. Prime Minister Rob Jetten visited the site to view the historical find.