Testing Requirements Ensure Design Goals Are Met
There are many reasons to verify the installed performance of windows, doors and curtainwalls. As the Architect/Specifier, you are responsible for the performance and quality of the exterior façade components. Issues such as workmanship details and warranty concerns all necessitate field testing of your installed fenestration products.
Lab vs. Real World
Most all windows, doors and curtainwalls are tested in a laboratory environment. Industry standards and guidelines such as AAMA/WDMA/CSA 101/I.S.2/A440 and AAMA 501 are typical voluntary specifications to which fenestration manufacturers validate certain performance characteristics. As specifiers of critical performance characteristics, laboratory results and findings are crucial to the initial development and planning of a given structure. As the term would imply, laboratory testing is a controlled environment, which typically provides the " best case scenario " as it relates to the potential performance of a given system.
Manufacturers pay particular attention to detail in the production of laboratory test specimens. The same attention may not always apply to production units, which roll off the production line. An infinite number of variables interact with the production unit, which may have a tremendous impact to the primary performances. Machining tolerances, human interaction and production scheduling/capacities have a direct effect on the quality and performance of a given product.
Field verification/testing can identify certain concerns or deficiencies, which may have originated from the factory that are pertinent to the performance expected by the owner. If field checks are done early in the installation phase, remedial work can often times be performed to correct problems before they have an adverse effect on the building. Typically, it is more cost effective and convenient to remediate before the unit is installed. In the case of large projects, important quality issues can be addressed or handled before the entire shipment reaches the job site.
Verify the Installation
In a manner similar to the actual production of the fenestration, several variables of the installation can have a direct impact on the performance of a product. Manufacturers typically provide a procedure for proper installation of their product. Deviations from this methodology can cause serious problems. The deviations are not always related to the installer's ability to follow approved practices, but rather at times the problem may originate from changing jobsite conditions. In either case, the installation of the actual project-related units is no longer controlled in a manner similar to the laboratory test specimen.
Hedge Your Bets
As with any product or service specified, manufacturers and contractors are called upon to provide a statement of quality and performance warranty . Most specifications have a warranty clause. As a specifier, the warranty can provide two things. First, the warranty and performance requirements can provide a minimum level of quality which can prohibit unwanted manufacturers. If a manufacturer can not provide a product which meets the warranty requirements, you may not want their products on your project. Secondly, warranty clauses usually define stipulations which protect the owner against failures or " less than expected " performance. Failures can include excessive water leakage or air infiltration, condensation, excessive deflections, faulty operation and deterioration in excess of normal weathering. What better way to verify some of these concerns than field testing of your window, door and curtainwall installations?