Pollution also eats away at the intricate stonework and the many beautiful carvings that adorn the buildings. The following section gives an overview of the conservation techniques being used to repair decades of damage and restore the beauty of the Parliament Buildings. Workers must re-point joints. That means carefully chipping the loose mortar out from between the stones. When repairing mortar, small tubes are pushed between the stones.
Workers then inject fresh grout into the gaps, some quite substantial in size.
The old copper roof on the south facade of the Centre Block had reached the end of its life cycle and was removed. Its concrete base, which was severely damaged by water, was repaired. Then, a new copper roof was installed. Even the familiar clock face underwent major work. The brass was brushed, the hands were covered with special new paint, and a special glass case was added to protect the clock's mechanism from dust and other pollutants.