43rd Annual Meeting – Architecture Specialty Group – May 16, Mid-Century Modern Wood Issues at the Weston Havens House by Kitty Vieth and Molly Lambert

Weston Haven's Section
Kitty Vieth, a senior associate at Architectural Resources Group, presented the work required to rehabilitate the most fragile structural conditions of the Weston Havens House. Molly Lambert, a conservator in private practice, discussed techniques she used to remove tide lines from interior cedar paneled walls.
The Weston Havens House is a Mid-Century Modern construction designed by architect Harwell Harris and built in 1941. It sits in the hills of Berkeley and has an 180-degree view of the San Francisco Bay. Weston Havens was the only owner of the house until his death in 2001. He bequeathed the property to the University of California Berkeley who now uses the house for visitors.
The house features a modernist design with upper and lower levels cut into a hillside. A curvilinear stair leads to the lower floors. There are two guest rooms with private terraces. The house contains original finishes at are intact. Kitty Vieth was brought in to evaluate the conditions of the materials and all building systems.
Upon evaluation, two high priority projects were defined. The first project was the Pedestrian Bridge that was in a state of near collapse. The bridge displayed a keel type construction with paired studs. Slow growth Redwood found in the Berkeley area was used to construct the Bridge. All of the wood showed deterioration, especially the structural components. Fortunately, the main beams were still structurally sound, but Vieth was not able to save the rafters and studs. The bridge was reconstructed using long slow growth of redwood that is already beginning to fade to grey and better match the original materials. A finish was used to protect the reconstructed bridge.
The second priority was the East wall and roof area. The seismic activity of the area was considered. Redwood boards were greyed, worn and cupping in some locations. Vieth consolidated and rehabilitated the windows and walls on East wall.
Molly Lambert spoke next about earlier work she undertook in the house when Weston Havens was still alive. This and other modernist structures often have redwood paneled interiors. When roofs leak tide lines form on the interior panels. Molly did two different campaigns to repair tannin tide lines on the interior of this house. She was able to get 80-90% of the tide lines out. Tannins in the wood migrate with water causing the darkened lines.
Her technique was as follows:

  • Wipe down the entire panel with wet cotton PVOH sponges (cellulose sponges) with grain.
  • Harvest some of the tannins with a swab using distilled water or spit and transfer to needed areas.
  • Don’t take too much of the tannins away.
  • In-paint with a tannic acid mixture as needed.