MSs return to revamped Siambr ahead of 2026 election

Members of the Senedd will return to the Siambr today (24 February) following the completion of a year-long redevelopment project.

The upgraded debating chamber has been expanded to prepare for the election of 36 additional Members in May 2026.

The works mark the most significant physical change to the Senedd building since it officially opened nearly 20 years ago on 1 March 2006.

Over the past year, Members have held Plenary sessions in the temporary debating chamber at Tŷ Hywel, located behind the Senedd.

With construction now complete, that space will revert to its previous role supporting the Senedd’s education and visitor programme, including sessions for schools and community groups.

Members will reconvene in the Siambr for Plenary at 1:30pm on Tuesday afternoon, with the first item of business set to be the weekly First Minister’s Questions session. Proceedings will be broadcast live on Senedd.tv.

Expanded

The redevelopment has expanded the Siambr to accommodate a total of 96 Members, reflecting reforms agreed ahead of the 7 May 2026 Senedd election.

The chamber’s original design incorporated removable back-wall sections, enabling future expansion without altering the building’s distinctive circular layout.

Key changes include:

36 additional desks

Improved accessibility, with internal steps removed

Upgraded broadcasting and ICT systems

Llywydd of the Senedd, Elin Jones MS, said: “This return to the Siambr marks an important milestone for our Senedd.

“Our debating chamber has been transformed to meet the needs of a larger parliament and a new era of Welsh democracy as we look ahead to the election on 7 May.

“This is a building shaped around openness, sustainability and the people we serve, and the changes reflect the next chapter in our democratic journey.”

The Senedd building has long been recognised for its environmental credentials, operating with natural light and ventilation, low-carbon heating and cooling, and extensive rainwater harvesting systems

The Siambr redevelopment has sought to maintain that sustainability focus, including:

Reusing Welsh oak from original Members’ desks

Refurbishing and reusing existing oak doors

Using slate from the same Welsh quarry as the original construction

Commissioning predominantly Welsh-based contractors

The redesign was overseen by RSHP, the architects responsible for the original award-winning building.

Ivan Harbour, Senior Design Director at RSHP, said the expansion had been anticipated decades ago.

“Twenty-five years ago, we set out to create an emblematic home for Welsh democracy, with the Siambr at its heart,” he said.

“This sensitive expansion, planned for all those years ago, allows the Siambr to accommodate more Members while preserving its openness, transparency, and the original spirit of participation.”

Milestone

The reopening of the expanded Siambr comes as the Senedd marks the building’s 20th anniversary and Wales prepares for a historic election.

The 2026 poll will see not only 36 additional Members elected, but also the introduction of a new electoral system and 16 new constituencies.

Voters will choose a party or independent candidate under a proportional list system, with six Members representing each constituency.