Repair and Rehabilitation of Residence 20 in Yosemite Valley

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During a snow storm following the Mono Wind event in January 2021, Yosemite Valley Residence 20 was impacted by a tree branch that fell on the building. The tree destroyed the left front corner of the building, including the rim joist, wall framing, ceiling and roof framing. Approximately 300 square feet (SF) of the roof was completely damaged, including the fascia, rafters, skip sheathing and cedar shingles.

During the stabilization and repair of the building, any salvageable historic fabric will be collected and stored for future use in the rehabilitation of the building. This would include any interior tongue and groove boards (ceiling), interior beaded boards (walls), windows, exterior sugar pine shake shingles, flooring, structural framing lumber, etc.

As the structural repairs are being made, in kind, the adjacent roof framing and shingles will be inspected for damage. If there is additional damage to the structure of the roof and exterior framing, those repairs will be conducted. The original finishes characteristic to the exterior of the building will be replicated from in kind materials, sugar pine shakes for the side walls and 16" cedar shingles for the roof. The exterior will be painted to match the remaining shakes, fascia and rafter tails. The undamaged windows will be refurbished and reinstalled, the damaged window sashes will be replicated, using the original as a template, and reinstalled. The exterior storm windows will be reinstalled, one was undamaged, three will have to be fabricated.

The build up of trees duff and debris that has turned into mulch and dirt around the drip line of the roof will be removed to replace the ledger board and shake siding that has been removed due to rot and decay. It has been replaced with a metal flashing that keeps the rodents and weather from entering the building from below. By removing the built-up dirt and debris from the outside of the foundation, the historic features can be restored, the building can be effectively rodent proofed and the foundation piers will be protected from settling due to water infiltration. Duff removal will be limited to a depth of 4" within the dripline of the building.

Prior to reinstalling the interior finishes, the house will be rewired and the panel replaced as per National Electric Code (NEC). The current wiring is a combination knob and tube and cloth jacketed wires, which have far exceeded their useful life. Existing finishes will remain undisturbed as much as possible and existing wall and ceiling openings will be reused, when possible to keep the historic finishes in tact. The electrical panel will be replaced with a current, code compliant panel box, with the proper grounding and bonding. This reduce the risk from fire that the historic wiring presents.

A fire sprinkler and alarm system will be installed as per NPS housing regulations and life, health and safety codes for permanent and seasonal housing. The design will consider the historic integrity of the buildings and have minimal intrusion on the interior spaces of the building. Any control equipment will be installed on the service porch adjacent to the existing utilities for necessary access for fire and maintenance personnel and the least impact on the historic interior finishes. Supply pipes will be concealed in the ceiling. The sprinkler pendants and escutcheons will be white to blend with the painted ceilings and walls.

The plumbing will be upgraded from cast iron and copper to PEX and HDPE pipe, any undamaged fixtures will remain in use.

The HVAC system will be upgraded to meet current code and reduce the use of electricity in the residence. The current system is baseboard heat to supplement the heat produced by the wood burning stove. The system will be upgraded to one that is primarily run by propane and using less electricity. The ductwork and the furnace equipment will be located in the attic or the crawlspace and utilize ceiling or floor mounted vents for minimal intrusion into the living space and minimal loss of existing historic fabric.

The walls will be insulated with rock wool insulation prior to the bead board and tongue and groove boards being reinstalled on the interior framing and ceiling joists. Interior surfaces will be painted to match existing. Carpet and padding will be installed in the bedroom to protect the existing historic wood floor from damage and any loss of historic fabric.

The Historic Preservation Training Center (HPTC) will be sending two representatives (historic architect and carpenter) to assess the structure and prepare a "prescription" detailing a methodology for historically sensitive repairs that will preserve much of the structurally sound historic fabric that remains (Demo plans and as-builts attached)

All work will be performed by the Yosemite Historic Preservation crew and licensed contractors that specialize in working on historic properties. All work will be supervised by the Historic Preservation crew or a COR familiar with the Secretary of the Interior's Standards for rehabilitation of historic properties to ensure that the proper treatments are being applied to the building. All repairs will be made with in-kind materials.