SMACNA Architectural Sheet Metal Manual 7th Edition — overview presentation

Sheet Metal As An Architectural Element Long life building material with a long history of use  Metals can be alloyed and formed to create unique metals and shapes to design unique buildings  Metal roofs are enjoying a resurgence of interest and use partially driven by code mandated cool roofs and new LEED requirements  Lowest-cost steep slope roof based on life cycle costing  Architectural sheet metal is the original green roofing solution  Many critical metal elements are invisible—Flashing!  Benefits Of Sheet Metal  Properly designed and professionally constructed and installed by experienced contractors sheet metal elements can last for centuries  Sheet metal fits all “green” building materials measures, especially recycled content – Recycled content: steel = 25%; roofing copper = >75%; – Energy efficiency per Florida Solar Research = lightcolored metal roofs VERY energy efficient  Soldered sheet metal joints are “sustainable” and do not require continuous maintenance—unlike ALL sealant protected joints History of Architectural Metals First used by the ship building industry—lead used in the 1500s with rolled copper use starting in late 1600s  New York City Hall used copper for roofing circa 1764  A copper roof was used on the rebuilt Old Senate Chamber in 1819; replaced in a 1900 renovation  The slate roof on the White House was replaced with sheet iron in 1804  The copper roof on the Old Church of Christ in Philly lasted from the 1830s to 1967; substrate failed  Early metal roofs were batten-style or flat-seamed until rolled tin production became common later in the 19th century with standing seam coming into general use  ASMM Contents  Roof Drainage Design & Systems  Roof Edging and Perimeters (Gravel- Stop & Fascia)  Copings  Flashing  Building Expansion  Metal Roof Systems  Wall Systems ASMM Contents - New for 7th Edition  Wall and Roof Penetrations  Louvers, Screens and Skylights  Interior Architectural Sheet Metal Elements  Other Metal Elements  Historical Restoration  Quality Control Procedures  Appendices – A through N – Soldering – Underlayments – Adhesives Roof Drainage Design  Roof Area  Rainfall Intensity  Metal Selection  Gutter Style/Design & Sizing  Downspout Style & Sizing  Expansion Allowances  Fastening Method Selection  Flashing Requirements FIGURE 1-2 RECTANGULAR GUTTER STYLES Built-in Gutters  Poses greatest risk of water intrusion  Soldered or welded joints only – Stainless steel and copper recommended  Use high-quality membrane underneath as a secondary underlayment  Specific shapes address water freezing  Attention to expansion allowances/design  Min. two downspouts per roof section Expansion Allowances  Gutter-specific expansion tables based on girth/profile/metal & predicted annual ΔT  Expansion of Building Materials table with various expansion coefficients – Must be used for fascia and copings with consideration of both metal and substrate  Flat seam roof expansion guidance over 30 feet …use batten seam design to allow for expansion  Copings and fascia also require joints that accommodate expansion between sections FIGURE 1-5 ALLOWANCES FOR GUTTER EXPANSION Roof Edging and Perimeter  Chapter covers a multitude of fascia design methods for flat roofing systems  Water should NOT be allowed to flow over the edge of built-up roofs!  Be careful with ladders and never step on the tops of fascia  Other reasons for “controlled” roof access beyond security FIGURE 2-6 CAP FASCIA - INSTALLATION Copings  The horizontal, top surface is the most vulnerable point for water to enter a wall – Water entering top of wall can “travel” distances  Copings provide a permanent water stop and reduce wall-related maintenance  Metal copings provide an attractive, finished appearance  Design for expansion with appropriate joints between coping sections Flashing  Third largest but most important chapter!