Ahwahnee Correct Balcony Deficiences

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This project will provide a permanent rehabilitation of the solarium ceiling and correct deck surface design deficiencies on four balconies at The Ahwahnee Hotel. The solarium ceiling was damaged in several locations during heavy rain events as a result of cracks in the lead deck surface on the second floor balcony deck. The solarium ceiling plaster is part of the historic fabric of the hotel. The 2nd floor balcony deck was replaced in 2005 with waterproofing and finish, therefore it does not have historic integrity. The remaining three decks were also inspected and included in the work scope to prevent future water infiltration and damage to fabric.

The construction scope of work for decks includes:

1. Remove the walking surfaces from each balcony and salvage for re-installation.
2. Remove lead sheet waterproofing on all decks and store on The Ahwahnee property (in back employee parking area east of cottages). Delaware North Companies (DNC) to sell lead and offset project costs with proceeds. All decks will be stripped of lead in its entirety with the exception of the lead located under the existing two sets of stairs on the 2nd floor balcony, which will remain as it will be too costly to remove and this area is a low risk for lead sheeting failure.
3. Install 3-ply modified bitumen plaza grade waterproofing directly over existing concrete deck substrate of the 2nd, 4th and 5th floor decks. For the 7th floor deck, a wood deck will be built up over the existing two tiered deck to provide a uniform slope. The 3-ply bitumen will then be installed on the wood substrate. Color of exposed bitumen shall be approved by NPS/DNC prior to purchasing material. The bitumen waterproofing shall have a manufacturer's warranty of 30 years.
4. Remove, salvage and re-install copper cap flashing pans and bronze cap plates at all locations. Install new copper where required.
5. On 2nd floor balcony, install two additional outlet scuppers to allow better drainage from deck.
6. At all decks, provide heat trace systems in new and existing downspouts to prevent freezing.
7. On 7th floor balcony, provide new safety guardrail. Design of handrail shall be with input from the NPS Historical Architect.
8. Following waterproofing installation, re-install walking surfaces in same pattern as existing.

Solarium work includes rehabilitating the lath and plaster finish on the solarium ceiling where damage has occurred. This will also include pull testing of the support wire and inspection of the structural bar supports to confirm structural integrity.