The number of architects hit by the governmentâ€™s decision to scrap the Building Schools for the Future programme is expected to reach at least 1,500.
RIBA has calculated that around one third of the countryâ€™s large practices â€“ those with more than 50 staff â€“ were involved with the abandoned initiative and have estimated at least 1,000 jobs will be affected.
Director of practice Adrian Dobson said large practices would be particularly affected by the decision.
But dozens of small- and medium-sized practices are involved with the Â£55 billion scheme, pushing up the number of architect jobs under threat significantly.
The impact on the profession will increase pressure on education secretary Michael Gove, who last night was forced to apologise in parliament over errors in the list of schools affected.
Jonathan Ellis Miller, director of 14-strong Ellis Miller, said the firm had seen work on BSF schemes stopped in Hertfordshire, Portsmouth and Rotherham.
â€œItâ€™s inevitable that people in the industry will lose their jobs because of this,â€ he said.
More than 700 schools due to be rebuilt or refurbished under the BSF programme have been ditched following the governmentâ€™s announcement on Monday that it was pulling the plug on almost all deals that had not yet reached financial close.
Gove said scrapping BSF would save around Â£5 billion, telling the House of Commons on Monday the scheme had been hit by â€œmassive overspends, tragic delays, botched construction projects and needless bureaucracyâ€.
The RIBA attacked his decision as â€œprofoundly detrimentalâ€ to the profession but some claimed the decision would enable architects to work more closely with schools on future projects.
Francis Gallagher, the principal of education at HKS, which is working on schools in Kent â€” the largest area affected with 36 projects pulled â€“ called BSF â€œimpossible and suffocatingâ€.
â€œIt should stand architects in good stead because in future architects will drive the renewal of school estates, not men in grey suits,â€ he said. â€œThe shackles are about to be thrown off. It will be the architect developing the brief with the end-user instead of the architect being controlled by the contractor.â€
Gove also scrapped funding for Cabeâ€™s dedicated design review service, worth almost Â£1 million a year. The design watchdog said it was making five redundancies as a result.
The government has hired a team to carry out a review of all future schools spending chaired by Sebastian James, operations director of electrical retailer DSG international whose brands include PC World and Currys.