Reinforced autoclaved aerated concrete (RAAC) planks were building materials used between 1950s and 1990s, primarily in public buildings such as schools and hospitals. They were used in fast assembly building projects, typically as roof panels. H+H UK Ltd were not involved with the manufacture or installation of these systems.
RAAC planks derive their structural strength from metal reinforcing bars within the planks. Failure occurs primarily when the reinforcing bars corrode. This typically happens when the planks have been exposed to water over a prolonged period of time. Corrosion weakens the bars and causes the plank to lose its intended loadbearing capacity. None of these failures are associated with the AAC material.
The aircrete blocks manufactured by H+H UK and used to build the foundations and walls of houses and low-rise commercial buildings do not use reinforcing bars.
Vertical Wall Panels – storey-high panels of aircrete used in wall construction – contain light reinforcements to ensure the panels are not damaged in transit. Vertical Wall Panels are manufactured to modern technical standards (EN12602). The reinforcements do not contribute to the structural performance of the panels.
H+H aircrete blocks and Vertical Wall Panels are not liable to the failures being seen in RAAC products.
H+H aircrete is manufactured to the standard BS EN 771-4 and BBA certification confirms that “walls constructed from the products will have durability equivalent to walls of traditional masonry.”