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68 SEPTEMBER 2016 COATINGSPROMAG.COM synthetic rubber FA materials can be applied at colder temperatures, some down to 20° F (-6.7° C), when compared to some water-borne materials that cannot be installed when ambient temperatures fall below 40° F (4.4° C). Lastly, it is important to consider if the material is compatible with incidental materials, such as sealants and primers. Should a solvent-borne FA air barrier be applied where it will come in contact with a transition membrane using a water-borne primer? Can it be installed over silicone sealants? ese are a few of the items to ponder prior to material selection. Courthouse Coating Over the years, we have encountered a number of FA air barrier failures. Fortunately, many of those were observed prior to the installation of outboard insulation and wall cladding — when there was still a chance to repair the issues. Failures occur due to several reasons, but they mainly come down to poor workmanship, improper training, and poor site coordination. A well-installed FA air barrier is heavily reliant on the installer's knowledge. Several manufacturers require that purchasers of their products be capable of installation, and they insist on train- ing and certification for installers and contractors. In addition to the installer, the general contractor and designer must be familiar with the limita- tions of the material and requirements for an air barrier assembly. Failures have occurred due to a lack of coordination between sub-contractors as well as sequencing by the general contractor. For instance, should the roof be installed before the air barrier is installed? Does the roof vapor barrier counter flash or overlap the wall 's air barrier? In the case of a build- ing in North Carolina, signs of a premature coating failure were obser ved. T he building was a new split- level county courthouse consisting of steel-frame concrete masonr y unit (CMU) and g y psum wall sheathing (GWS) backup walls w ith brick masonr y unit (BMU) veneer, rigid insulation installed over an FA air barrier applied to the substrates. T he roof assem- bly was not installed prior to the air barrier installation. It would consist of a single-ply roof membrane over an insulated metal deck. e air barrier assembly required the installation of an SA transition membrane at changes in substrate plane (i.e., inside and outside corners) and transitions between different substrate types (i.e., GWS, CMU, steel, and concrete). Transition membrane installation was also required over steel relieving angles and around window openings and wall penetrations. e SA membrane required the application of a primer to the substrates prior to installing the transition membrane over the CMU, GWS, and steel substrates. According to the installer, the installation was progressing well, until the FA air barrier contacted the substrate primer. Based on the site visits conducted by the air barrier auditor, installation The peeling failures were also observed on the outside corners of the building. In addition, it rained three days after the FA air barrier was installed, and large amounts started to run down the wall. The failures were observed around window rough openings. Peeling Air Barrier