Why are there cracks in the steeple? Steel and plastic.

There are four steel rods placed within the masonry of the tower that would have supported a taller steeple if ever one was added. Those steel rods are very long to support such a structure, and each is set 10” back from the face of the bell tower, the walls of which are 90” thick. The rods would have been made of high-carbon steel available at the time (the sanctuary was completed in 1811), and high-carbon steel is prone to rust and the expansion of that rusting steel caused the cracking in the surface over the years. Thankfully none of the repairs or cracks are structural in nature and the cracks are being cleared of deteriorated material and filled with bricks and mortar that is of similar composition.

The cracking very likely occurred in recent decades after fire damage was repaired in 1960. At that time, the architect suggested elastomeric paint, which was again suggested during repairs after Hurricane Hugo in 1989. Elastomeric paint provides a strong, long-lasting, watertight coating. The benefits of the paint in this application ended up creating a setting well-suited to rust metal. Since masonry absorbs moisture, the bell tower masonry took in moisture over the years and the elastomeric paint, effectively a plastic coating, kept the moisture from being able to evaporate. That held moisture likely exacerbated the rusting of the embedded steel rods in recent decades. The bell tower has begun to look more pink as the crew strips the white elastomeric paint to be replaced with a masonry paint more appropriate for this application.

Patterson explains why there are cracks in the steeple, why the bell tower looks more pink than white at the moment, and the interesting things we've come to learn during the restoration of the steeple.