In early August, scaffolding installation began as the first step toward a much-anticipated removal of black debris netting on the Cathedral’s main level. Once it is put in place, the Cathedral’s earthquake-repair engineering team will be able to gain close access to portions of the vaulted nave ceiling, more than 100 feet above the floor, which had not been accessible during a previous earthquake assessment. The team’s investigation of three representative areas will translate to repair drawings and specifications that contractors may use to prepare bids for repairs to the entire ceiling.
It will take approximately two weeks for SafWay Services llc to erect scaffolding from the west balcony and north transept balcony to the clerestory level (approximately 61 feet in height from the nave floor). This conventional steel pipe scaffolding will be topped by a “dance floor” or decking of rated plank-layered plywood, a safe platform from which to install rolling towers that ultimately will provide access to various heights of the ribbed masonry ceiling. Scaffolding will also be installed in the first two bays of the nave via a slightly different approach so as not to interrupt worship and other Cathedral activities in the nave. Wiss Janney Elstner Associates, Inc., known as WJE, will conduct the inspection and expects to have completed investigations, reporting, bid drawings, and specifications by mid-November for potential restoration contractors. The selected contractors should start the repair work by mid-January, with the netting coming down in phases as the work is completed.
In the nave and west balcony, where the ceiling was last accessed for conservation in 1995, anticipated areas of repair include open mortar joints, joints with failing sealant, masonry staining, and cracked stone. The north transept ceiling presents the added complication of vaulting finished with Akoustilith tile, a cast stone tile patented in 1916 by the Guastavino family whose firm was responsible for many of the nation’s most historically significant timbrel vaulted tile ceilings and interiors. The tile had significant absorptive qualities that improved the ability for readers and preachers to be heard in worship spaces. Today, when the spoken word is augmented by electronic audio equipment, most facilities that had employed this tile are exploring coatings that will improve acoustics for music. The Akoustilith at Washington National Cathedral will be inspected by Building Conservation Associates, Inc., to see what damage might have occurred to it over time. Recommendations for repairs and treatments to this tile will be coordinated with an acoustician and submitted at the same time as those for the work on the masonry vaulting elsewhere in the nave.