WEI was contacted for emergency stabilization of many stone veneer blocks of Birdseye marble that were loosened by the 2011 earthquake in the DC area. The “marble” is geologically a limestone quarried in Utah with many fossils and oncoids throughout. The stone was specifically chosen from Utah when the church was constructed in 1931 for the Church of Jesus Christ of Latter-day Saints. Above the chapel, the tower and steeple extend over 100 feet into the air. The tower has a steel superstructure with concrete decks and brick walls faced with over 16,000 Birdseye marble blocks.
During the work it was discovered that the pointing mortar was stronger and less permeable than the stone and had caused damage around many joints. Many old patches used on the stone to patch natural clay pockets were also failing.
Loose stones were carefully removed from the building and organized on the ground in a way that they could be easily identified for reassembly later. Tests were then conducted by conservators to find a comptible mortar for the stone in strength, vapor permeability and color. In addition, cleaners were evaluated to remove soiling and gypsum crusts from the stone. Consolidants were also tested, however due to the high amount of clay content in the calcareous stone, the consolidants were not effective. Large blocks that were no longer stable were removed and replaced with replica Birdseye marble made by taking an impression of an existing stone block to recreate the unique fossilized texture of the stone.