Texas Architect Sept/Oct 2007: Design Awards
Texas Architect is the official publication of the Texas Society of Architects, each edition features recently completed projects and other editorial content largely written by AIA members in Texas. That collective participation was the basis of Texas Architect’s recognition by the national AIA with a 2010 Institute Honor for Collaborative Achievement.
texas architect 9 / 10 2 0 07 92 Control of water intrusion into building assemblies is best achieved by establishing a continuous “drainage plane” that extends across, and in some cases through, all the building enclosure elements and assem- blies. These include windows, precast, sealant, flashings, moisture bar- riers, and roofing systems. Elements such as brick, stone, metal panels, and plaster provide environmental protection as “weather barriers” but should not be considered moisture barriers. An important test of the suc- cessful detailing of the “drainage plane” is the ability to trace its “line” throughout all the details of the building enclosure assemblies—without lifting the pencil. In reality, due to gravity’s downward pull on water, detailing to prevent water intrusion can be successful even with some minor discontinuities. One example is the typical punched window installation with a masonry veneer. Sealant typically ties the wall moisture barrier to the window frame, protecting the head and jambs as shown in Figure A. Properly placed to the frame, this provides for the continuity in the drainage plane. A common detail at the sill is the use of a “pan” to guide water collected and guttered within the window back to the exterior. However, without additional gaskets or sealant, this may not provide a complete barrier against air infiltration. See Figure B. Study your standard details to see how many have hidden paths for air. Similar to a drainage plane, an effective air barrier should be traceable throughout the building enclosure, and not cross an unsealed joint or porous material. note that the drainage plane and air barriers often can Local Councils Promote Education The successful design and construction of a building’s exterior enclosure defines the aes- thetic sense of a building, it secures protection from a variety of weather conditions, and today it is an integral part of strategies for sustainable building design. In recognition of the importance of the build- ing enclosure design, the Building Enclosure Council Initiative was created in May 2004 through a partnership between the American Institute of Architects (AIA) and the Building Enclosure and Environmental Council (BETEC) of the national Institute of Building Science. Its mandate is to create a series of BEC chapters across the country to “promote and encourage discussion, training, education, technology, transfer, the exchange of information about local issues and cases, relevant weather con- ditions, and all matters concerning building enclosures and the related science.” With an initial goal of nine local councils by 2007, there were 17 as of July, with another two or three cities considering establishing their own BEC. Sponsored as an autonomous profit center by local AIA chapters, each local BEC is an interdisciplinary forum with architects, engi- neers, consultants, manufacturers, contractors, educators, and owners. Texas has two councils, known as BEC Dallas and BEC Houston. To learn more about the BEC program, ac- cess information at www.bec-national.org and the national Institute for Building Standards at www.nibs.org. To participate in the Dallas chapter, contact George Blackburn III, AIA, at firstname.lastname@example.org. To join the Houston chaptercontaact or Andy MacPhillimy, AIA, at email@example.com. F igure A F igure B P. 91 IM Age Co Py rIgh t PA l I r Ao A nD A nDre w Johnso n, 2007 Is toCk Photo