By Doug Harnsberger
Spring 2012 Germanna Newsletter
At 1:51 pm on August 23, 2011, the terra firma beneath Salubria rumbled and heaved the stately 1757 Georgian-style house.
By the time the quaking action had subsided, the 5.8 magnitude Mineral Earthquake had ruptured and twisted both of the twenty foot high chimney stacks twenty degrees, and sent hundreds of pounds of loose bricks cascading from the severed chimney caps down onto the shingled roof below.
The cascading bricks hit the roof with such a powerful force that seven of the interior roof rafters fractured within the attic.
In addition, the quake’s rolling and rocking opened up a dozen new stress cracks in the once-solid brick perimeter walls.
Just as many of the houses and churches in the nearby Town of Culpeper were rocked violently, the Mineral Quake shook Salubria with similar effects.
In its wake, the quake left considerable structural and cosmetic damage upon the oldest and finest brick residence in Culpeper County.
The Germanna Foundation’s first urgent priority for stabilizing Salubria’s earthquake damage was to deconstruct the twisted and ruptured chimney stacks before they might collapse through the roof.
Within a few days of the earthquake, the renowned historic preservation crew of Price Masonry from Madison Heights, Virginia worked from two opposing bucket lifts to gingerly wrap the chimney stacks with fiberglass straps in order to stabilize them, before beginning the brick-by-brick deconstruction process.
All of the displaced chimney bricks were brought down to grade in buckets, where they were cleaned of mortar and stacked for their eventual reuse.
About 30% of the brick were cracked or damaged beyond reuse by the quake’s actions, so a mix of matching replica brick will be required for the two chimneys’ reconstruction.
In anticipation of the chimney reconstruction work that is scheduled to begin on April 15, 2012, the Germanna Foundation placed an order in January for three thousand sand-molded, handmade, oversize brick with Old Carolina Brick in Salisbury, N.C.
These custom-made bricks will closely match Salubria’s original chimney brick in size, texture and color.
The reconstruction work on the two chimneys is expected to take approximately two months, which means that the chimneys’ elegant twenty-foot-high profile above the roofline should be fully visible again for everyone to enjoy by mid-June.
Repairing the Fractured Roof Rafters
Quake damage to the original circa 1757 attic roof rafters was less obvious than the chimney destruction.
The above photo shows project Germanna member Robert Ellis pointing to one of seven fractured rafters in the attic. The fractures all were located just below the heavy purlin structural member at the rafters’ midspan.
Instead of simply removing and replacing these seven broken rafters, however, the Germanna Foundation will repair them in situ and restore to their original locations prior to the earthquake’s dislocation.
New “sister” rafters will be inserted adjacent to each of the repaired rafters to assume the active roof load.
The historic rafters will be relieved of the ongoing roof stresses, and preserved-in-place for future architectural historians to observe and analyze.
Repairing the Quake-induced Stress Cracks in Salubria’s Brick Walls
Lateral and vertical earthquake forces moving through a solid brick wall often will produce diagonal stress cracks, as seen in the above photo.
In this particular example along a Second Floor partition wall, the bricks pulled apart about an inch, leaving a continuous diagonal line of severed bricks and localized plaster damage.
Salubria’s brick wall stress crack restoration work will begin in April of 2012, after the last freeze of winter.
All of the fractured wall bricks across the cracks will be removed and replaced with matching whole bricks.
The stress crack cavities within the walls will be filled with a special casein liquefied mortar injected into the wall cavities.
Price Masonry’s lead preservation mason Jimmy Price has promised to give us another of his signature restoration demonstrations using the casein injection process, so that all those who wish to learn firsthand about this masonry conservation technique may benefit from his expertise.
We will announce the day and time of the demonstration (sometime in May) on the Germanna Website.
Researching “Best Conservation and Restoration Practices” for Salubria’s Upcoming Roof Restoration Work
The Salubria Restoration Design Team of Legacy Architecture, LLC and HITT Contracting has made recent field trips to Colonial Williamsburg’s Wythe House, James Madison’s Montpelier, George Mason’s Gunston Hall, Washington’s Mount Vernon and Historic Kenmore in Fredericksburg to observe “best conservation and restoration practices” as these institutions have applied them.
The roof restoration projects executed by Peter Post, Historic Roofer, at Montpelier, Mt. Vernon and Gunston Hall has provided us with exemplary models for the kind of high-quality decorative wood shingle work that we shall achieve soon at Salubria.
The existing decorative shingles on Salubria’s roof date back to a 1982 installation, so they are over three decades old now.
We have found evidence in the attic that several of the historic rafters suffered significant water damage from the prolonged rainwater leaks through the roof.
The Germanna Foundation has committed to repairing the damage to the Salubria’s exquisite heavy timber roof structure and to installing a new decorative cedar shingle roof this summer, from June through September.
Mr. and Mrs. Russell Hitt, and HITT Contracting, Inc. have generously made a challenge grant of $195,000 to ensure the stabilization and conservation work begins as soon as possible.
“To everything there is a season,” Ecclesiastes tells us. So, this season – this year – is Salubria’s “time to build up.”
The Germanna Foundation respectfully solicits your contribution, at whatever level you can help to match the HITT Challenge Grant and counteract the destructive forces of the Mineral Earthquake. Salubria’s preservation depends now on our collective response.