The February 28, 2001 Nisqually Earthquake hit local churches harder than perhaps any other group of historic buildings. Part of the reason for this disproportionately large and costly amount of damage lies in the nature and complexity of the designs and deferred maintenance. The pool of funds for maintenance has waned with the dwindling populations of many urban congregations. In spite of this, a few churches, like Trinity Episcopal, located at the corner of 8th Avenue and James Street, at the edge of First Hill and downtown, have devoted themselves to the long-term preservation of their historic facilities.

The process of analysis, planning, repairing and restoring the church will take years. The church's historic sanctuary, with its English Gothic massing, detailing, and stonemasonry, was heavily damaged, and has been red-tagged since the quake. The vacated sanctuary is now pocked with discrete holes used to gauge damage and slippage. The building's corner spire, one of its most distinguishing features, separated slightly from the rest of the building during the earthquake. The latter was so unstable that crews were reluctant to work on that part of the project.

This problem and others have been successfully tackled over the past year and a half. Though the church and its architects, engineers, and contractors have years to go before the church's full recovery, the initial efforts and benchmarks are significant.

A Plan for God's House

Trinity Episcopal Church has been considering ways it might further its mission and generate revenue toward that end. Trinity called on Bassetti Architects, a Seattle-based firm with a varied portfolio of new construction and preservation work, to help with this planning effort. In addition to its sanctuary and adjacencies, Trinity owns land near the building that it hopes to develop into housing. Immediately after the earthquake, the church called ABS-EQE engineers, a local firm with experience with historic structures, to conduct an initial analysis and shoring. John Riley was the primary engineer for the Trinity project. Bassetti was called again to help with the long term planning of the repairs and restoration.

Architecture firms do much more than shape the appearance of old and new construction. In this case, Bassetti (specifically Don Brubeck) acts as a general manager for the project, coordinating the work of many disparate contractors and subcontractors to make sure all efforts interconnect. In the case of Trinity Church, the earthquake damaged many internal systems and affected the temporary use of spaces within the facility. Repair and restoration work often involves the temporary dismantling of historic features, or partial replacement of historic materials. Some of the elements employed to retrofit the building will have an impact on the building's historic character.

Any change in a primary system, like the wiring or HVAC systems, requires a holistic planning approach that is governed in large part by an understanding and appreciating the church's historic significance.

Stonework

Trinity's stonework is one of its most defining features, and received a great amount of consideration within the master restoration plan. Before the earthquake, the lime mortar had deteriorated and in some places been replaced by Portland Cement. Spalling, or flaking masonry, occurred where this cementitious material was used. Repointing historic masonry with Portland Cement was considered a "preservation" measure until recently. Like sandblasting historic brick buildings, applying Portland Cement causes long-term damage by degrading the historic bricks or stones in contact with the material. In the restoration, specialists have matched new mortar with the historic lime mortar, and have taken great pains to match the jointing details as well. The new joints match the historic ones: very wide ¼ beaded joints that somewhat resemble the veins of a leaf.

In some places, the stone had to be completely dismantled. Planning for this involved detailed drawings of the stone walls, with each stone numbered, so that each could be reinstalled exactly as it had been. Walter Bazylewcz, a skilled stone mason and carver, was in charge of this piece of the plan. Bazylewcz's other work includes ornate carvings, traditional column capitols and stone wine cellars.

Brubeck notes that a lot of engineering firms without historic preservation experience discredit the structural integrity of historic masonry. Traditional stonework relied upon an empirical understanding and calculation of strength. Because no one builds with these techniques anymore, the strength of historic masonry is hard to measure. This unknown element disturbs engineers, banks, and insurance companies that finance older masonry buildings.

Structural Problems

Engineers dealt with the shaky corner tower by bracing it with steel pipes inside and steel cables outside the structure. This took place soon after the earthquake, and crack monitors were installed to measure shifts. Crack monitors are simple - two targets on a wall that move back and forth. Some movement throughout the year is expected and is typically associated with seasonal "freeze/thaw."

As contractors dismantled the stone for repairs, they noticed that the wooden sill supporting the rafters was rotted. In the past, the church noticed leaks and made makeshift repairs, but had not forestalled the rot. The comprehensive plan for the building solves this longstanding problem by adding steel tension rings at the base of the rafters. A borate treatment was applied to the timbers to arrest dry rot. This works much like plant food sticks - waxy borate treated rods are inserted into the wood and gradually dissolve over time as water leaks in. The borate kills microorganisms that cause rot.

Better than Ever

Earthquake damage challenged the congregation and its rector, Paul Collins, to raise funds quickly, so that repairs and restoration could occur on schedule. The church has done a phenomenal job, with the help of a fundraising consultant. To meet their capitol campaign goals - which exceeded 5 million - the church sold off some of its property. Collins, an upbeat and energetic practical optimist, mentioned that the effort has helped the congregation understand what the building means to them. In a few years, Trinity will stand much stronger and better protected against future disasters than any time in its history.

Project Team:
Principal Architects: Bassetti Architects, Don Brubeck, Project Manager
Engineering: ABS-EQE Architects, John Riley, Primary Project Engineer
General Contractor: Bailey Construction
Stonework: Keystone Masonry, Walter Bazylewcz
Hazardous Materials Abatement: Prezant and Associates
Greg Myers, URS Corporation, Owner's Project Manager

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