Award of Excellence: Special Projects Category
St. Anne's Court
Submitted by Sika Corporation
St. Anne’s Court is a historic Grade II ‘Star’ Listed Structure which was designed and built in 1937 by the famous minimalist architect of the ‘Modern Movement,’ Raymond McGrath. In this structure McGrath also pioneered the use of Oregon Pine timber forms to produce an architectural boardmarked concrete finish.
By the mid 1990s, the carbonation process had progressed beyond the depth of the steel and, where moisture ingress had also occurred, expansive corrosion of the steel had led to detrimental cracking and spalling. A full survey identified all the existing damage and further indicated a large number of exposed concrete surfaces with a high risk of damage due to the progressive loss of protective alkalinity.
The damaged concrete was repaired with polymer modified cementitious mortars, special cosmetic grades of which were finished by hand tooling to recreate the original board texture. To protect against further damage development, the surface was then treated with a penetrating corrosion inhibitor to form a protective layer on the surface of the steel. Finally, a water-based anti-carbonation and waterproofing coat was applied over the entire restored board profile concrete in the originally specified off-white color.
This project symbolizes what can be achieved by the use of 21st century repair and protection technologies in combination with a sympathetic approach to the refurbishment of our heritage.