During the construction of a project, water testing is performed on glazing systems in the field to verify they are meeting the project requirements set forth by the owner and architect and that the systems and their components are performing as intended and expected. Testing will either A: verify that both the installation of the system and surrounds as well as the manufactured components of these systems are performing or B: reveal conditions and locations that need further attention as a result of water penetration observed during the test. Although the glazing systems are tested and rated under laboratory conditions, it is important to test assemblies in the field to account for installation adjustments, outside environmental conditions, shipping, handling, and delivery effects.
How is Quality Assurance Water Testing Performed?
Quality assurance water testing is generally performed per ASTM E1105 which is the Standard Test Method for Field Determination of Water Penetration of Installed Exterior Windows, Skylights, Doors, and Curtain Walls, by Uniform or Cyclic Static Air Pressure Difference.
The test involves constructing and sealing an air chamber to the interior or exterior of a glazing assembly, supplying air to a chamber mounted to the exterior or exhausting air from a chamber mounted to the interior while spraying water across the outside face of the assembly from a uniform spray rack, at the required rate. The test simulates the conditions of a wind-driven rainstorm and is performed at a specified test pressure differential across the assembly following Procedure A (uniform pressure differential) or Procedure B (cyclic air pressure differential) of the ASTM standard.
The field water test pressures are generally spelled out in the project specifications. If there are no test pressures specified for the project, then pressures are typically calculated per AAMA 502 Voluntary Specification for Field Testing of Newly Installed Fenestration Products and AAMA 503 Voluntary Specification for Field Testing of Newly Installed Storefronts, Curtain Walls, and Sloped Glazing Systems which in general specifies to test the assemblies with a 1/3 reduction of their laboratory tested water pressure. Note that if assemblies are required to be tested after a building occupancy permit has been issued or more than six months after the product has been installed then the AAMA 511 Voluntary Guide for the Forensic Evaluation of Water Intrusion at Fenestration Products shall be used accordingly.
As defined in ASTM E1105, water penetration is the penetration of water beyond a plane parallel to the glazing (the vertical plane) intersecting the innermost projection of the test specimen, not including interior trim and hardware, under the specified conditions of air pressure difference across the specimen. During the test, points of water penetration are recorded and the results are noted as a pass or fail. Note that water contained within drained flashings, gutters, and sills is not considered a failure since these components are designed to re-direct the water to drain back out to the exterior of the building. Interior finishes should not be in place at the time of testing to allow for an unobstructed view of the assembly and its surrounding conditions
AAMA 501.2 which is the Quality Assurance and Diagnostic Water Leakage Field Check of Installed Storefronts, Curtain Walls, and Sloped Glazing Systems is sometimes specified by the architect as a means of quality assurance testing for field installed systems. This test also referred to as the “AAMA Nozzle Test” does not require an air chamber or a spray rack, but rather a brass nozzle connected to a hose and control valve to adjust the water pressure. Note that this test is not to be used on operable assemblies and is not used to test the water performance representative of a wind-driven rain event.
For quality assurance testing, GCI recommends using ASTM E1105 test method to conduct the testing at a specified air pressure differential, creating the effects of a wind-driven rain event. However, in some conditions, AAMA 501.2 testing may be more appropriate for logistical reasons for instance at large fixed assemblies such as curtain walls and skylights where the air chamber cannot be easily placed and sealed to the assembly.
Testing should be conducted as early in the project construction process as possible. We recommend either a stand-alone mock-up or an in-place mock-up be accelerated so that the typical assembly, its components, and wall conditions can be tested. This will verify that any issues will be caught and corrected early before the full installation is underway. Exterior finishes surrounding the test assembly should be in place so that testing is performed on the final detailed conditions for the exterior envelope. Testing should continue throughout the construction phase of the project so that quality control and standards are met throughout. All relevant parties including installers, manufacturers, architects, and owners should be invited to witness the testing.