The Government is backing the product with nearly £1M in funding from Innovate UK, the newly-named Technology Strategy Board.
The basic design concept was developed by a Glasgow-based modular walling system company, which then worked with the Steel Construction Institute and Caunton Engineering to refine the product in advance of building the first major sections.
Caunton is now one of a handful of construction companies that have won R&D funding to develop nuclear technologies.
Use of these factory-made steel bricks could pave the way for large sections of nuclear power stations to be built off-site.
This would speed up construction, improve build quality and reduce project risk.
Innovate UK Chief Executive Iain Gray said: “The product will help our civil nuclear industry set new standards.”