Present: Fred Aperton, Bill Barry, Matthew Bronski, Susan Close, Rick Detweiller, Ross Diekel, Taya Dixon, Jack Glassman, David Hart, Richard Jarvis, Michael Lynch, Bill Mack, Doug Manley, Henry Moss, Brian Roche, Susan Schur, Malcolm Smiley, Jonathan Smith, Bob Thomas, Sara Wermiel 1. Heavy Timber Framing Systems and Mill Reuse: Sara Wermiel explained the evolution of the common system for building textile mills in New England - a distinctive form of heavy timber framing called "slow-burning construction." Derived from English precedents of the 1820s, slow-burning mills featured masonry bearing walls, timber (or iron) posts and girders, and plank floors (without joists). In addition, slow-burning mills were compartmentalized and had fire suppression equipment. The result was an effective form of fire-resistive construction - the solid floors and large-dimension members, combined with protected shafts, would slow a fire's spread, while the sprinklers, on-site water service, and mill fire brigade would extinguish it. This development was markedly different from Fireproof Construction that employed noncombustible structural materials, notably iron framing and brick or concrete floors. She distributed copies of an annotated isometric section illustrating Standard Slow Burning Mill Construction that was prepared by John R. Freeman, a notable 19th c. civil engineer and official with one of the Associated Factory Mutual Fire Insurance companies, which helped to codify slow-burning construction, from a lecture he gave in 1894. Sara's clear description of this most advanced form of American mill building served as a background for her current studies of adaptations of heavy timber framing for urban lofts, such as those found in South Boston. City factories, stores, and warehouses had requirements that would not permit the use of slow-burning construction without modifications. For one thing, the floor loads in textile mills were generally significantly less than those needed for warehouses and stores. Sara's exploration of warehouses built by the Boston Wharf Company and other developers in the late 19th c./early 20th centuries revealed another important modification: girder and beam framing, rather than girders only, which resulted in less frequent, but massive, wooden columns. The more closely spaced timber beams in the urban lofts were sometimes carried on the top of girders and sometimes hung from iron hangers. This construction created floors that could carry live loads 3 to 5 times greater than the floors of late 19th century mill buildings. Mill buildings were typically designed to carry 50 - 60 pounds per square foot. Boston's building code for 1885 and 1892, in effect when many Boston Wharf Co. warehouses were erected, required buildings used for storage to support 250 psf. While Sara's presentation focused on the design and construction evolution of these buildings as originally built, Henry Moss presented a series of images focusing on the ad hoc changes (both intentional and unintentional) that frequently occur to mill buildings over time. Anecdotes and images illustrated intentional modifications and additions that frequently departed from Standard Mill Construction and the surrounding structural system, often in combination with deterioration such as flood damage, timber decay, and other long-term degradation. Henry's slides conveyed both the unpredictability of Mother Nature and the impressive ability of long-standing timber structures to survive and adapt. His examples of solutions to these long-term ills (such as installation of boric acid impel rods into joist ends that are embedded in potentially damp masonry, and stethoscopic plumbing diagnosis and rehabilitation of old sprinkler systems at MASS MoCA) were in the spirit of the Yankee ingenuity and frugality that we associate with the pragmatic 19th century timber and masonry structures of New England. 2. APT Conference: Matthew Bronski warned everyone of the July 15 deadline for early registration for APTI's conference spanning September 17-20 in Portland, Maine. Go to http://www.apti.org/portland2003/ for last minute registration information. Tobin Tracey has led the effort to organize the Portland Conference. Julie Klump has organized a course on timber preservation in association with a maritime workshop, while Amy Cole-Ives has organized the historic masonry workshop (outline schedule attached). Additional registrants are needed for both the Timber and Masonry sessions to avoid cancellation of these workshops. 3. Stained Glass Association of America Conference, June 2004: Brian Roche announced this conference, which will be sponsored by the studios of Serpentino and Lyn Hovey. Brian asked the committee to contribute ideas for the content of the conference. Next Meeting featuring John Lannon: Rehab and Restoration at the Boston Athenaeum September 11, 2003, Thursday, 8: 00 a.m. The Architects' Building, 52 Broad Street, 5th floor, Boston
Henry Moss AIA, Matthew Bronski, and Sara Wermiel, co-leaders and scribes
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