B09_Amendment_3_FOWA_852_141693_HPTC_Record_of_Treatment_2009_0003.pdf

Preservation of Fort Washington Light House 80

Fort Washington Park Fort Washington, MD

HISTORIC STRUCTURES RECORD OF TREATMENT

HISTORIC PRESERVATION TRAINING CENTER

Department of Interior National Park Service

4801A Urbana Pike Frederick, MD 21704

Narrative Statement Preservation of Fort Washington Light House 80

Fort Washington, MD, FY-09 Work Order# 117282

Project Narrative

This Historic Record of Treatment records work performed by the National Park Service, Historic Preservation Training Center (HPTC) on Fort Washington Light House 80 in Fort Washington Park during May and June of 2009. The purpose of this project was to stabilize and preserve Light House 80. This consisted of the replacement of 30 feet of the north-east corner post, selective repairs to the timber framing as well as selective replacement and painting of the siding. This document contains a summary of work completed as well as copies of the Project Agreement, correspondence, account summary, weekly reports, photographs, and field sketches.

All preservation work was performed in compliance with the Secretary of the Interior’s Standards for the Treatment of Historic Properties and approved by NEPA and Section 106 compliance procedures.

Project History

12/09/07 Section 106 Compliance Approval 01/09 Draft Project Agreement PMIS #138711 03/09/09 Final Project Agreement 04/14/09 Direct Charge Authorization initiated.

04/21/09 Pre-Con Meeting 05/18/09 Design Change Approval #1 06/11/09 Close-Out Meeting

Description of Project

HPTC was contacted by the National Capitol Region in late 2008 to provide a day labor crew for the emergency stabilization of Light House 80 in National Capitol Parks East, Fort Washington Park. In the prior three to five years, volunteers had installed modern siding over the original siding on the north, west and south elevations. The condition of the original siding was thought to vary from fair to bad. This modern siding had begun to fail due to improper prep work and moisture problems. It had also altered the historic size and appearance of the light house. The Project Agreement titled Preservation of Fort Washington Light House 80 was first distributed for review in January 2009 and approved in March 2009. The tasks covered in the Project Agreement Scope of Work include the removal of all modern siding, selective replacement of the original siding, and the shoring and partial replacement of the north east corner post.

Clearance

Section 106 clearance was reviewed by National Capitol Region cultural resource staff and approved by the Superintendent of National Capital Parks East on December 9, 2007.

Summary of Work

Project work began on May 4th with the mobilization of the day labor crew, equipment, tools and supplies from Frederick, Maryland to Fort Washington, Maryland. Site work began on the north east corner as siding was removed to open up the corner for post replacement. As structural repair/replacement continued on the north and east elevations, siding and trim work commenced on the south and west elevations. To this end scaffolding assembly began on the north and east elevations and progressed to the west and south elevations. The orange day hazard triangles installed over the siding were relocated to the scaffolding exterior during the project and returned to their original locations at its conclusion. Adjustments to the Scope of Work were made as unforeseen conditions were revealed and are detailed in Design Change Approval #1.

Corner Post:

The crew replaced 90-percent of the northeast corner post with Southern Yellow Pine provided by Chesapeake Wood and fabricated on site. To facilitate post replacement the structure was stabilized with shoring between the belfry roof frame and second floor roof. Part of the belfry frame and the second floor flat metal roof were removed from around the post including three belfry rails, metal roof pans, sheathing, four rafters, two soffits and two fascia boards. Tie rods connecting the north east post to the remaining three posts were cut and the damaged portion of the post was removed up to the belfry frame. The portion of the post left intact was dressed with a 24-inch half-lap to receive the replacement at the juncture of the removed belfry rails. The replacement post was installed with the aid of a crane and operator provided by G&G Welding.

The replacement post and two belfry rails were fastened to the remaining post at the half-lap with 14-inch stainless steel bolts. G&G Welding welded the tie rods back together. The second floor roof frame, sheathing, fascia boards and soffit were rebuilt around the post. The metal roof pans were reinstalled, re-soldered and painted black.

Frame and Sills:

Structural frame replacements include the left jamb on the first floor window, two entrance door jambs, two studs between the sill plate and the lower left cross beam of the north elevation, two studs on either side of northeast corner post just below the second floor roof. Epoxy and “Dutchman” repairs performed include four belfry rails, the west elevation second floor window sill and sub sill, the northwest corner post and the north elevation sill plate.

Siding & Trim:

Removal of the modern siding revealed two types of first generation “Dutch” lap siding: 5 ¼” tongue and groove boards on the first floor and 5 ½” clap boards on the second floor.

Replacements were milled to match from Southern Yellow Pine by Cavetown Planing Mill. The

1x12 belt course board and water table cap separating the first and second floor on the east elevation continued around the remaining three elevations. This was replaced with belt course and water table milled from Spanish cedar on the north and east elevations. On the south and west elevation the water table had been defaced during modern siding installation, but was left intact as a record of the structure’s history. As a design improvement water table was fabricated and added between the first floor siding and sill plate to minimize water infiltration. The fascia board and soffit on the north and east elevation was replaced as were the exterior side panels of the entrance door dormer. Siding and trim was scraped to sound paint and sanded. One coat of oil based primer and two coats of acrylic finish paint were applied to all existing and replacement components of the exterior envelope.

Dormer Roofs:

It was discovered that the four dormer roofs were not original and had not been properly ‘counter flashed’ from behind the siding, but that the flashing had been attached to the siding exterior.

This counter flashing was adjusted and fastened to the frame as replacement siding boards were installed around the dormer roof. The metal roof pans were painted black to match the main roof.

Project work was completed on June 16th as the day labor crew demobilized and returned with tools and equipment to Frederick, Maryland.

Profile of 1st and 2nd floor siding.

Light House 80 before rehabilitation.

Northeast corner post before rehabilitation.

Siding on the north elevation was in poor shape and was completely removed revealing the timber frame.

The metal roof and frame were opened up at the northeast corner and the post was cut back to sound wood with a half lap joint.

Thirty feet of the north east corner post was replaced with 8 x 8 southern yellow pine.

Selected Photographs