Arup has confirmed that it has been appointed to investigate a defective underfloor heating system that has delayed the opening of a £22m hospital in Wales by a year

Rhondda Valley hospital was already delayed by more than a year, and was due to open in June, but a recent test of the heating found floors were reaching a temperature of up to 40°C, which is deemed too hot to walk on.

David Lewis, director of finance at Cwm Taf NHS Trust, said it had commissioned an independent review to “establish if there were any defects and, if so, what timescale would be needed to get the hospital back up and running”.

Clive Barnby, chief officer of Pontypridd & Rhondda Community Health Council, said he understood the floor tiles had now begun to buckle under the heat, but said no legal action had yet been considered. “We’re just trying to establish who is at fault,” he said. “We’re waiting for the report into where the blame lies, whether its with the contractor, architect or design engineer.”

Cowlins, the contractor for the scheme, declined to comment, and architect Nightingale Associates was unavailable.

An Arup spokesperson said:

“We’ve been asked as an independent third party to assess what’s happened, but this is a confidential report and I can’t make any further comment at this time.”