Built in 1888, St. Mark's Church in Catonsville, Md. is a two-story building constructed of granite and masonry with a footprint of 80- by 200-feet. Throughout its history, side naves and a front foyer were added to the structure using brick masonry. Today, coated stucco covers the side naves and an ornamental stucco coating surrounds the entire building. Age had taken a toll on the establishment and repairs were necessary.

An original scope of work presented to the contractor called for the replacement of the gable copingstones, random stone pointing, repair and coating of the ornamental limestone stucco and crack repairs. However, after a visual and structural investigation by Structural Preservation Systems (SPS), it was determined repairs were needed to deteriorated mortar joints and spalled ornamental stucco. To avoid damaging the surrounding areas of the building, no power tools could be used - only hammers, chisels and other manual tools. All repairs were performed by hand.

The rehabilitation began with the cleaning of the gable capstone, which was then spot-repaired with a bluestone repair mortar. The copingstones were then sealed with a natural stone treatment and the cross-joints were sealed with a lead weather-cap. The spalled and deteriorated areas of ornamental stucco detail were repaired using a premium grade stone repair mortar. Next, these details were coated with a mineral stain. The stain chosen allows vapor permeability and maintains the stone-like appearance of the details while preventing further water infiltration and subsequent deterioration. Additional repairs were made to the cracks in the stucco by removing the cracked areas and filling them with a specialty repair material that matched the color and texture of the stucco. Another repair area involved the wooden trim and details, including doors and soffits, which had rotted in various locations. New wood was installed in those areas, and the wood in all of the locations was coated with an industrial-grade exterior paint. SPS also replaced the protective glass that covered the stained glass windows. To achieve an aged appearance that matched the existing glass, the new pieces were kiln-fired.

Despite a significant change in scope, the project was completed according to the revised schedule, within the original budget and with no OSHA recordable incidents.