Christ’s College was modelled on the public schools of England and moved to its present site in 1856. The Openair Classroom block has an Historic Place Category 2 and was originally constructed in 1932.

Earthquake repairs, structural strengthening and alterations to the Openair Classrooms included the application of a 150mm thick 30MPa wet sprayed concrete over existing brick masonry walls over an area of approximately 550m².

As a result of a series of concurrent shotcrete projects being awarded simultaneously and the intermittent programme staging of these works it was necessary to engage a subcontractor Aardvark Concrete Services Ltd for all wetspray works with BBR Contech managing and providing local support allowing the Wellington based spray crews to fly in, spray walls and return in minimum turnaround times.

A wood float finish was provided after application of shotcrete with walls wet cured for 7 days. The works were carried out in four stages between August and December 2012.