Japan's iconic parliament building to undergo first major renovation in 90 years amid safety concerns

Japan's iconic parliament building in the heart of the capital is set to undergo its first major renovation since being built nine decades ago, amid safety concerns, media reports said Sunday.

Renovation at the National Diet Building will begin in 2030 and is scheduled to be completed in eight years, with an estimated cost of 60 to 70 billion yen ($382 million to $446 million), Tokyo-based Kyodo News reported.

The estimated cost may shoot up as material costs have surged in recent years.

A key component of the renovation plan is the fitting of a seismic isolation layer below the foundations of the nine-story building to allow it to remain in use during the renovation.

Spreading over 53,460 square meters (575,438 square feet), the building was completed in 1936 after 17 years of construction, with its pyramid-shaped roof and granite facade.

Constructed from reinforced concrete, the building contains the chambers for the House of Representatives and the House of Councillors.

A room used to receive the emperor when he visits the Diet is made entirely from Japanese cypress finished with fine lacquer.

An inspection of the structure in 1981 found the building conformed to quake resistance standards that had been updated around that time.

But a 2019 checkup conducted by an expert panel established by parliament raised concerns about the aging structure.

A report compiled in 2023 warned of risks of falling objects because of warping in the steel frames of the central tower and legislative chambers.

The report recommended a renovation plan to enhance the structure's seismic resilience.