David Stutzman
Specifiers may be one of the best kept secrets on the design team. Specifiers, especially independent specifiers, typically interact with the architectural team, only. Even then, the interaction may be limited to project architects and project managers. It is rare that specifiers have an opportunity to meet with owners and contractors during the specification production process.
So when given an opportunity to meet owners or contractors, this specifier is more than willing to accept. The Architectural Glass and Metal Association (AGMA), extended an invitation to attend their annual winter meeting and to present design and specification trends from a specifier's point of view. Here is what we discussed in the hour allotted.
Quality Assurance
Architects are looking for better control over manufacturers, fabricators, and installers to ensure the overall quality of the completed construction. Currently the only means to exercise control is to specify minimum qualifications. What might that be - years experience, similar projects, references? Must manufacturers approve, certify, or train installers? Even though specifications include such requirements, actually complying with the requirement may not be possible.
If gaps in required qualifications are discovered after bidding, will architects and owners actually reject contractor proposed manufacturers, fabricators, and installers? It is unlikely because rejection and replacement will result in increased costs.
The Finishing Contractors Association International (FCA) initiated the North American Contractor Certification (NACC) program. The initial certification is available for glazing contractors as a business entity. FCA is completing the initial certification program for glazing craft-workers as individuals. Certification will be available to every glazing contractor and craft-worker. Certification is provided through an independent organization as an ANSI and ISO compliant program.
Performance
Building envelopes are more and more complex. The complexity brings a new emphasis on performance. It is no longer adequate to rely on manufacturers' published details and test results for standard systems when the systems are used in customized ways. Consequently, the architect relies more often on an envelope consultant for specialized expertise in designing and documenting exterior walls.
Increasingly the architect and owner elect to use design assist to enlist the contractor and installer's expertise during the design process, too. The design becomes a shared responsibility, although in this scenario, the architect maintains the design liability.
Design assist allows the architect, contractor, and subcontractor to use a collaborative process to achieve an end more quickly and efficiently - presumably. The design assist goal is to produce acceptable shop drawings as the design is completed. This will allow the architect to approve the shop drawings at the completion of the design assist process.
Architects and envelope consultants must resist the temptation of specifying indeterminate performance. Without defined performance, proving energy code compliance will not be possible. Low E glass is a common example. This glass type is presumed for exterior insulating glazing to meet current energy codes. Low E insulating glass comes in literally thousands of configurations - each with different performance, color, and reflectivity affecting the building aesthetics.
Detailing
Architects are expecting energy analysis and thermal modeling of typical and unique project conditions. The manufacturers, fabricators, and installers must be willing to create the models to demonstrate the product will not produce adverse conditions at the building interior - like condensation and potential mold. To permit the analysis, the architects must specifically define the project design conditions rather than leaving it to the contractor's imagination.
Complex facades require customized details to suit the project specific conditions. Architects cannot know what customization may be required to accommodate interfaces between individual components when the manufacturers' standard details do not apply. So architects are asking fabricators and installers to develop project specific shop drawing details. Show the adjacent materials, the interfaces, and intersections to demonstrate an understanding of the requirements for the completed installation. Simply showing the edges of the abutting construction and labeling the work as "by others" is no longer acceptable practice.
Specifications
Some architects, certainly not all, are using BIM. Most seem to use BIM for graphics and visualization, not for embedded data. Architects report that they wish to work generically with the building model for as long as is possible. This suggests that design decisions may not be final until well into the construction documents phase. Therefore, embedding model specification data entry early in the design process may be counterproductive. Few AGMA members reported using or having access to architects' building models, so data availability may be moot.
Preliminary project descriptions (PPD) describe projects by building system and assembly. The arrangement - UniFormat (created by estimators) - aligns with BIM objects one-to-one and with contractor's early project estimates. PPDs are beneficial for collecting owner's project requirements and the architect's performance criteria. PPDs can be written to document performance before the final design solution is known. Using BIM to show the building arrangement, a PPD to describe the systems and assemblies, and an estimate for the project costs, all arranged by the same format allows for easy value analysis to select optimum design solutions before the final design stages. Proactively employing value analysis as part of the design process will help preclude the need for reactive value engineering after the design is completed.
The specifications process is a risk management process. Specifiers gather and analyze data continuously in conjunction with the design drawing development. Specifiers, because of their exposure to many more projects than architects, are able to leverage the experience to help identify alternative materials and systems to satisfy design conditions. Specifiers because of their direct connections to manufacturers are able to coordinate the technical requirements of the various building systems. And because the specifications control the project quality, real-time collaboration between the specifier and the estimator will help ensure budgetary control needed to successfully complete the project.