Stair Protection

Stairsteps

Figure 3. The plywood treads extended past the nosing on the historic steps with soft fiberboard set in place beforehand as additional protection. Drawing: Christina Henry.

Both the marble and the wooden stairsteps were identified in the planning stage as being vulnerable to damage and excessive wear during the renovation work. The decision was made to lay a temporary wooden covering over the existing stairs in a manner which would provide for maximum protection of the historic fabric without hindering daily use of the stairs by the construction crew (see figure 3). A sheet of soft fiberboard served as a cushion between the wooden covering and the historic stairsteps. The floorboards extended approximately one inch past the existing treads to provide better protection for the delicate nosing. For each step, a second piece of fiberboard was cut to rest against the riser, The temporary wooden treads applied over the fiberboard were cut out of plywood rather than planking, since plywood has a greater resistance to cracking and curling in such wide widths. For the risers, less expensive planking sufficed. In both cases, fire retardant wood was specified.

In assembling the temporary steps, power-driven screws of specified length were used. Screws rather than nails were chosen in order to avoid pounding damage to the masonry joints and the relatively thin historic marble panels used in the staircase construction, and also to reduce the chances of damage during disassembly.

Wooden stops measuring one inch square were first screwed onto the end of the plywood treads; the plywood set onto and against the two fiberboards used on each step; and then the planking used for the risers was set in and secured in place with screws. For disassembly, the process was reversed.

Balustrade

Once the temporary wood floors were installed, the balustrades were encased in plywood (see figure 4). For the sections running on top of the handrail, 5/8 '' or 3/4 '' plywood was used, cut wider than the handrail to permit attachment of 2 by 4 blocking on the underside for securing the 1/2 '' plywood side walls away from the balustrade (see figure 5). For padding, neoprene was glued to the face of the blocking closest to the edge of the handrail as a cushion in case the covering was jarred. The handrail was cushioned further by soft fiberboard glued to the underside of the plywood top. After the top section was assembled, the side plywood walls were cut and attached; the side walls were additionally blocked out wherever the newel posts protruded beyond the balustrade (figure 6). The entire assemblage was secured tightly with judicious use of braces and blocking or where necessary was screwed to the temporary wood floor.

Cross section of stair showing encased balustrade

Figure 4. This cross-section of one of the staircases shows that the entire historic balustrade was temporarily encased in wood during the renovation work. Drawing: Christina Henry.

Figure 5. As with the step detailing, the temporary protection over the balustrade and hand railing used plywood padding, blocking, and strew fasteners to minimize possible damage. Drawing: Christina Henry

Figure 6. The balustrade on the left side of the photograph has been entirely encased in plywood to protect it from damage. Note that the kick-out at the end is due to the protrusion of the newel post. Photo: Charles Fisher.

Stairwells

A temporary eight foot high wall was constructed to protect the historic wood paneling, marble and decorative trim typically found along the stairs. The wall covering consisted of plywood attached to a wood frame that had been designed so as to require no anchor attachments to the historic wails (see figure 7). The triangular shaped sections of the frame which supported the plywood rested on the plywood floor covering. Wherever the frame abutted historic material, a thin neoprene pad was glued to the wood beforehand to avoid scratching. For greater rigidity, 2 by 4 sleepers were added in various locations to connect the triangular sections of the frame. In cases where the historic handrail protruded considerably and was not temporarily removed during construction, the triangular sections were not pre-assembled, but rather constructed in place around the railing.

Figure 7. The temporary wall covering going up the stairs consisted of plywood mounted on a wooden frame. Neoprene padding was used where the fame abutted the historic walls. The method shown here requires no fasteners to be used, avoiding possible damage to the decorative walls. Drawing: Sharon Park, A.I.A.(Click on image to enlarge)

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