Washington National Cathedral (Earthquake Repairs Phase I)

Washington National Cathedral (Earthquake Repairs Phase I)

Restoring a Shaken Landmark with Award-Winning Repairs

In a city known for its monuments, some say the Washington National Cathedral towers above the rest. At 300 feet tall, this century-old English Gothic relic is the sixth largest cathedral in the world and the second largest cathedral in the United States. Built over the course of 83 years, the spiritual center was in a state of construction for most of the 1900s. But its most recent round of renovations — led by our DAVIS team — was far from planned.

On August 23, 2011, a 5.8 magnitude earthquake rattled the region. It was the largest earthquake to strike the East Coast since 1897 — leaving the Cathedral with fallen finials, twisted pinnacles, and cracked stones. And while these damages were certainly disheartening, they put the Cathedral's ongoing fundraising efforts front of mind and helped to fuel the funding to make the repairs a reality.

The project called for a general contractor with deep expertise and respect for historical preservation, the technical know-how to manage complex structural reinforcement, and the logistical leadership to perform repairs without impacting the Cathedral’s 700,000 annual visitors. It was the perfect project for our team, and we’re proud to have played a part in this landmark’s history.

  • Project type
    Cultural + Community
  • Architect
    Wiss, Janney, Elstner Associates, Inc.
  • client
    Protestant Episcopal Cathedral Foundation; Washington National Cathedral
  • awards
    WBC Craftsmanship Award, Interior Stone and Marble, Scaffolding and Rigging; AGC of DC Washington Contractor Award, Renovation/Restoration, Contractors overs $400M

Masters of Masonry

It’s hard to fathom, but a mere minute of ground motion was more than enough time to cause severe damage to the Cathedral’s intricate stonework. Fragments of limestone and mortar had fallen over 102 feet from the vaulted ceilings and littered the main floor. Flying buttresses — made of solid stone — ​had been displaced. And while it was important to repair every crack, preserving the historic integrity of the Cathedral’s original stone and mortar was our team’s top priority.

Unique Challenges

Surrounded by Scaffolding

If asked to summarize the complexity of the Cathedral earthquake repairs in one word, it would be accessibility. After all, it’s one thing to repair damages to a ceiling of standard height, but it’s entirely different when dealing with a Gothic-style Cathedral. That’s where extensive scaffolding comes in. As the general contractor leading the charge, it was our job to provide stable, unobtrusive access to every lofty, hard-to-reach space in need of cleaning or repair — ​while also safeguarding the public areas to protect tourists and congregants from fallen debris.

Three Dimensions of Support

The scaffolding, both interior and exterior, was the framework of our team’s work. At the exterior, fixed scaffolding was erected to envelop the stone buttresses and apse walls to an overall height of approximately 150 feet, to access the tops of the pinnacles. Once erected, the exterior scaffolding allowed us to clean and repair stone and stained glass window damage to the apse buttresses and Te Deum stained-glass windows. We also applied lighting protection to the apse buttresses and to the cross at the apse roof.

To reach the vaulted ceiling of the interior, trusses were hoisted 80 feet from the floor and set on a two-foot-wide clerestory level. These trusses then supported a main platform, affectionately named the dance floor, with fixed scaffolding on top. This scaffolding was erected so that it followed the shape of the vaulted ceiling, but remained within four to six inches away from the delicate stone.

A Milestone on the Road to Restoration

At the start of our work, we received a 15-page document outlining all of the Cathedral’s activities that would require us to pause construction. But despite the multitude of work stoppages that came from coordinating around Cathedral activity, not a single event was cancelled because of our repairs.

After we finished Phase I repairs in June 2015, the client expressed its appreciation by hosting a private Evensong for everyone involved in the job, including the DAVIS construction team and our families. It was a special event for all of us. And while the Cathedral has a multi-phase restoration schedule ahead, the quality of the completed Phase I work is unrivaled. The beauty lies in the inability to notice the repairs — ​everything blends seamlessly into the original design, just the way it should.

Photos courtesy of Washington National Cathedral, by Colin Winterbottom