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Present: Jack Alvarez, Bill Barry, Chelsea Blanchard, Matthew Bronski, David Coe, Taya Dixon, David Fixler, Jack Glassman, Sarah Gray, Jean Marie Hall, Marie Helms, Kimberly Konrad, Ellen Lipsey, Laura Mackowiack, Arthur MacLeod, Doug Manley, Albert Rex, Deborah Robinson, Brian Roche, Suan Schur, Deborah Slaunwhite, Malcolm Smiley, Jonathan Smith, and Erin Tobin 1. Towers and Steeples: This month's focus topic looked at technical lessons learned from committee members' work on towers and steeples Though the subject towers varied greatly in size, age, materials, and location, extensive deterioration was all too frequently the common thread. Given their brutal exposure to the elements, their open belfries that allow rain to pour in, and, for masonry towers, their lack of heating (no mitigation of freeze/thaw cycling) , it's no surprise that many of these towers now beg desperately for help. Arthur MacLeod of MacLeod Consulting described his structural rehabilitation of the Monson, MA (not Maine) Town Hall, a remarkable 1884 granite building designed by George E. Potter, and listed on the National Register. In March 1998, hundreds of pounds of stone fell from the west face of the tower, crushing the granite entry steps below, where, quite luckily, no one was standing (once again, only The Guardian Angel of Falling Masonry in Massachusetts seems to have prevented a fatality). Years of neglect and freeze thaw damage led to the localized collapse. The only noticeable maintenance was a useless 1960's thin smearing of pink Portland cement mortar over the surface of the mortar joints. Arthur was called in to offer a second opinion after another engineer recommended rebuilding the entire tower (all wythes, everything) from the ground up at an estimated cost of 3 million dollars. For approximately 1/10 that cost (325K), Arthur and Chapman Waterproofing were able to complete localized repairs and stabilization of the masonry (using Cintec anchors and rebuilding portions of the outer wythe), and even rehabilitate wood windows and repair copper roof flashing as well. Arthur mentioned that committee member Sara Chase investigated the original paint schemes for the windows. Carl Jay of Shawmut Design and Construction presented the heroic reconstruction of the lost tower of Memorial Hall at Harvard. Fellow committee members Elizabeth Randall of Harvard and Judy Selwyn of PTA were part of the project team. The team was fortunate to have detailed, exquisite original drawings from Ware and Van Brundt (c. 1876) upon which to base their work, as well as decades worth of photos. As was typical in the day, the drawings were thoughtfully laid-out with the plans, elevations, and even details for the tower all on the same sheet, as opposed to the numbingly page-turning way we would scatter those drawings throughout a large drawing package today. Carl praised the craftsmanship of the workers, particularly Heather and Little (noted for their work on the Library of Congress), who recreated the ornamental copperwork in their shop, including some complex 3-D elements for the cresting, and shipped them to Gilbert & Becker for installation. The completed top of the tower, with its red copper gleaming in the Cambridge sun, was lifted and crane-set in a spectacular event watched with awe by preservationists, contractors, students, and passers-by alike. David Coe and David Fixler of Einhorn Yaffee Prescott described their current work on the Pine Street Inn. David Fixler presented a brief history of the building. It was a Boston Fire Station until the 1950's, when it was abandoned for roughly a decade before being occupied by the Pine Street Inn in the 70's. David Coe, the Project Architect, described the building's problems and their solutions. David stated that the mechanisms causing distress in the brick are complex, but in a nutshell, differential expansion between the face brick and the back-up are shearing the headers and causing cracking in the vertically-confined face brick on the shaft portion of the tower. Counter-intuitively, David said they found repair of the corbelled, machicolated deck area of the tower, and the equally elaborate lantern atop the deck, to be "easy", while they found repair of the simple, planar brick shaft of the tower to be quite challenging. The elaborate upper portions will remain composite (monolithic thick-walled) brick, repaired with Cintec anchors and localized brick repairs/rebuilding. The lower shaft portion will be turned into a brick veneer, drainage-plane wall assembly. Their solution for the shaft involves a subcutaneous steel frame, concealed between the face brick and the back-up brick, to support the new face brick. David credited John Wathne of Structures North with much of the creative thinking behind this solution. Given the significant daily movement they are anticipating between the new face brick and the back-up masonry, even details such as deep window returns (where new face brick meets old brick) become challenging. The design is currently out to bid, with work scheduled for this spring. Matthew Bronski of Simpson Gumpertz and Heger presented "Five Lessons from Five Towers in Five Minutes". The first tower was First Church in Cambridge, where SGH investigated the cause of cracking in a sandstone belltower where the full bell swings (not just the clapper). Brent Gabby installed triaxial geophones (similar to accelerometers), rung the bell, and measured velocities well below the threshold necessary to cause cracking, illustrating the first lesson; "don't just assume the cause, use testing to prove or disprove a hypothesis". The second was the Chapel at Bowdoin (Richard Upjohn). The second lesson was to consult with knowledgeable peers, whether near or far. Brent consulted with Luigia Binda, regarding grout injection techniques for vacuous collar joints, and tested the technique in a small area on a mock-up. Ms. Binda is a structural engineer in Milan who in the 1980s set-up EEC testing program on these techniques, which have been used extensively in Italy. Binda and Gabby concur that these techniques simply don't work when the collar joint is filled with sand (don't believe it if your grout salesman tells you otherwise). The third tower was a tiny gem of a chapel in Williamstown Mass, where quartzite stone with metallic mineral staining was masquerading as seam-faced granite. The highly vitreous quartzite (a sample was passed around) made it difficult to bond to mortar, almost like building a tower from glass block. The lesson was on the value of mock-ups prior to construction. In this case, sample mock-ups were critical to finding the right mortar. The fourth was a granite church tower in Brookline, built in 1909, and showing considerable distress (a current joint project with Neal Boornazian and Jean-Marie Hall of ICC). Church records show that even as early as the 1940's, architects repairing the tower were writing of the extensive deterioration and cracking, illustrating the lesson that "just because it's an old building does not necessarily mean it was built well originally." The fifth was a wood steeple, completely rebuilt about a decade ago after a fire, where areas of the wood cladding are already rotted. Given the severe exposure, new-growth pine siding can deteriorate quite rapidly. The lesson with wood steeples, whether new or old, is using a critical eye to design every minute detail to shed water. With restoration work, Matthew urged us to avoid the temptation to simply rout-out wood deterioration and fill with epoxy: first figure out why that area rotted (as opposed to other nearby areas) and detail so as to discourage future deterioration - slight modifications that don't change the appearance can make a tremendous difference in long-term durability. 2. Reviews of Recent Events Landmarks of the Future Event, Old South Meeting House: Susan Schur reported disappointment with this event at Old South Meeting House. The question repeatedly put to the distinguished panel by moderator Michael Dukakis was: "Aside from Boston City Hall, what will be the Boston landmarks of the future?" Evidently, most of the panelists persisted in discussing their favorite unrelated topics (e.g., the suburbs of Paris), without ever answering the evening's main question. APT Annual Conference, Asilomar, Monterrey CA: David Fixler reported that the site for the conference (natural and architectural) was wonderful, although the conference tours were less than stellar. David attended a Masterpieces of Carmel tour of notable buildings, including a Frank Lloyd Wright house. The tour turned out to be a "drive-by", without entrance to a single house. Jack Glassman appreciated the less formal, more interactive nature of the presentations compared with APT conferences of the past, and enjoyed the increased time for group discussion. He also was pleased to find that the sessions included more philosophical questions and discussions than at past APT conferences. 3. Fenway Park: Kimberly Konrad reported on encouraging recent events. Two of the seven groups bidding on the Red Sox are entertaining plans to renovate the historic ballpark, while none of the seven have adopted the Red Sox highly-lobbied, partially-taxpayer-funded plan to demolish the historic park and build a larger retro-look megastadium next door. One of the leading bidding groups, that of Tom Werner (NY) and Les Otten (ME), have proposed a favorable and strangely familiar plan for renovating the existing ballpark on its current site, retaining the features that make it unique and significant, while adding an upper deck and luxury suites to help the ballpark compete with modern retro-parks with greater seating capacity and revenue generating features. The Werner Otten plan, coming from a well-financed reputable bidding group, was much more warmly received by the Red Sox organization, their consultants, and the Boston Globe than a largely similar plan proposed by the "tree-hugging wussies" of Save Fenway Park! (as Bob Ryan once referred them in his Globe column). 4. Future BSA Historic Resources Committee Meetings: The November meeting will have a focus topic on vernacular siding, including Erin Tobin discussing asphalt shingle siding (yes, siding) and Heli Meltsner on vinyl siding in the realm of preservation. The December meeting will include Sara Wermiel presenting the broadly talented and learned architect/engineers who shaped our great structures in the latter nineteenth century. In January, Catherine Truman will discuss her recent efforts in Mostar, Bosnia. Subsequent meetings will feature a focus topic on materials conservation, and discussions of possible improvements to MA Code Chapter 34. 8: 00 AM, Thursday, November 8, 2001 Focus Topic: Vernacular Siding The Architects' Building 52 Broad Street, Fifth Floor, Boston |